Maintenance and Repairs of Tv-II

VOCATIONAL HIGHER SECONDARY

TEACHERS’ SOURCE BOOK

Government of KeralaDepartment of Education

2006

STATE COUNCIL OF EDUCATIONAL RESEARCH AND TRAINING (SCERT)

Vidyabhavan, Poojappura, Thiruvananthapuram-12

MAINTENANCE AND REPAIRSOF RADIO AND TELEVISION

SECOND YEAR

Prepared by:State Council of Educational Research & Training (SCERT)

Vidyabhavan, Poojappura, Thiruvananthapuram -12Kerala

E-mail:[email protected]

Type setting by:SCERT Computer Lab.

©Government of Kerala

Education Department2006

This Teacher’s Sourcebook on Maintenance and Repairs of Radioand Television introduces the teacher to the main principles andpractices of the revised pedagogy which is activity-based, process-oriented and learner-centred.

The realisation that learning is not mere storing information in memoryand that real learning is construction of knowledge throughobservation, comparison, classification and analysis has led us to givea new thrust to the teaching-learning process at Vocational HigherSecondary level to make it more meaningful and learner-friendly.

This sourcebook has been developed primarily for the benefit ofteachers who teach Maintenance and Repairs of Radio andTelevision at Vocational Higher Secondary level. The subject matterhas been dealt with utmost care, in tune with the revised curriculumand pedagogic principles. It is hoped that this book will enable theteacher to provide suitable learning activities for effective learning.

The success of the approach depends upon the vision and commitmentof the teacher. They are expected to make use of this sourcebook atall stages of their teaching process. It is also expected that the teacherwould seek help and guidance from other sources like libraries andwebsites.

Hope that this sourcebook will help the teacher to develop the skillsand experience required for effective classroom transaction.

Creative criticism and suggestions for improvement are most welcome.

With regards,

Thiruvananthapuram Dr E. Valsala Kumar July, 2006 Director

SCERT, Kerala

Foreword

Dear Teachers,

CONTENTSCONTENTSPart I

General Approach ................................................................... 6

Subject Approach .................................................................. 24

Teaching and Learning Strategies .......................................... 30

Syllabus .................................................................................. 40

Planning .................................................................................. 43

Evaluation .............................................................................. 53

Curriculum Objectives .......................................................... 64

Part II - Unit Wise Analysis

1 . Radio Communication ...................................................................................7 0

2 . Audio Equipments ............................................................................................7 5

3 . Television Transmission ................................................................................7 9

4 . Monochrome Television Receiver .............................................................8 4

5 . Colour TV Receiver ........................................................................................9 1

6 . Video Equipments .............................................................................................9 8

7 . Satellite Communication ............................................................................ 1 03

8 . Advances in Television Technology ...................................................... 1 08

Part III

Practical Evaluation ............................................................. 114

Practicals ............................................................................... 116

Appendix .............................................................................. 211

Part I

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Teacher’s Sourcebook VHSE

SIGNIFICANCE OF VOCATIONAL EDUCATION

The ultimate aim of education is human refinement. Education should enable thelearner to formulate a positive outlook towards life and to accept a stand which suits thewell being of the society and the individual as well.

The attitude and potential to work has determined the destiny, progress and culturaldevelopment of the human race. As we all are aware, the objective of education is to forma society and individuals having a positive work culture. The educational process expectedin and outside our formal schools should concentrate upon inculcating concepts, abilities,attitudes and values in tune with these work culture. Hence vocationalised education cannotbe isolated from the main stream of education. In another sense, every educational processshould be vocationalised. However due to our inability to utilize the resources wisely,scarcity of job opportunities is a severe issue of the present society. For overcoming thisdeep crisis, emergent techniques have to be sorted out and appropriate researches have tobe seriously carried out. It is in the sense that the content and methodology of VocationalHigher Secondary Education have to be approached. The need for meaningful linkagesbetween the world of work and world of education is well recognized. The essence of therecommendations made by various commissions and committees is that the vocationalisationshould be the main feature of the future system of education at the higher secondary stage,it can be extended to school level also.

Vocational education is system of education which intends to prepare learners foridentified occupations , opening several areas of activities.

The Vocational Higher Secondary course was envisaged as a part of the NationalPolicy on Education with the noble idea of securing a job along with education. Therelevance of vocational education is very great in this age of unemployment. This educationsystem, which ensures a job along with higher education stands aloof from other systemsof education.

GENERAL APPROACH

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This education imparts the life skills required by the youth to enter the world of workand assuming the responsibilities of adulthood. As per the expert meeting report (2001) ofUNESCO, the life skills are grouped under 4 categories. They are

1. Skills for personal fulfillment

2. Skills for living in society

3. Skills for dealing with changing economies

4. Skills for dealing with changing work patterns.

Vocational Education ensures fulfillment of manpower requirement or nationaldevelopment and for social security for the citizens through self-employment. It also helpsto reduce the migration of rural youth to urban areas and thus helps in rural development.

The learners of Vocational Education get an opportunity to avail one yearapprenticeship training in industries to improve their practical skill. During the course ofstudy, on the job training (OJT) for 10 days in a year is arranged to improve the skill andefficiency of the learner. This education system motivates the attitude towards self -employment through Production Cum Service Training Centres. (PSTC)

OBJECTIVE OF VOCATIONAL EDUCATION

The National policy on education has accorded very high priority to the program ofvocationalisation of education, considering the following objectives.

1. To fulfill national goals of development and the removal of unemployment andpoverty.

2. To impart education relevant to increased production and productivity, economicdevelopment and individual prosperity.

3. To make available skilled work force at all levels to alleviate the ruralunemployment and for the development of nation.

4. To develop environmental awareness to ensure sustainable development.

5. To develop vocational aptitude, work culture, values and attitudes of thelearners so as to enrich the productivity of the nation.

6. To develop entrepreneurial competencies and skills of learners for self relianceand to undertake gainful self employment.

7. To facilitate the expansion of higher education and explore future opportunitiesthrough innovative guidance and programmes.

8. To develop vocational competencies, creative thinking in the related areas andfacilitate training.

9. To create awareness on mental, physical and social health.

10. To acquire awareness about different job areas and to provide backgrounds foracquiring higher level training in subjects concerned.

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Learning

Learning is construction of knowledge through a continuous mental process. It isadvancement through adding and correcting in the light of comparing the new issue withthe previously learned concepts. Learning is an intellectual process rather than the merememorization of facts. Learning is a conglomeration of a variety of activities like problemsolving, finding out co-relations, prediction, arriving at conclusions, rational as well ascritical thinking, finding applications, grouping for other possibilities and extracting thecrux when opportunities are provided for intellectual processes learning will becomeeffective and intellectual ability will get strengthened.

Theoretical foundations of learning

Education is the best device that can be adopted for creation of a new society. Itshould be democratic in content and process and should acknowledge the rights of thelearner. It should also provide opportunity for better citizenship training. The concept ofequality at all areas should get recognition in theory and practice. There should be consciousprogramme of action to develop nationality, humanness and love against the encroachmentof sectarianism of caste and religion. The learner should become cognisent of theimplications of privatisation, liberalisation, globalisation etc.

They should develop a discrimination to use the acquired learning as a liberativeweapon.

They should be able to view education and life with the perspective of social wellbeing.

A basic awareness of all the subjects needed for life is essential for all learners.

The remnants of perspectives formed in us during the colonial period still influenceour educational philosophy. The solution to the present day perplexities of the societywhich approaches education on the basis of competitions and marketisation is only acomprehensive view of life.

It is high time that education was recognized on the basis of the philosophy of humaneducation. The human approach to education has to reflect in its content, learning processand outlook. The perspective of 'learning to be' and learning to live together as expressedby the UNESCO and the concepts of existential, intrapersonal and interpersonal intelligence.

The basis of new approaches on curriculum and teaching- learning process are derivedfrom the developments took place in the east and west of the world.

When we begin to see the learner at the centre of the learning process, the teachingprocess has to be changed timely. It is the result of the rapid growth and development ofScience and Technology and Pedagogy. If we want to undergo the changing process, wehave to imbibe the modern hypothesis regarding learner that they have

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• great curiosity

• good imagination

• numerous other qualities and interests

• independent individuality

• interest in free thinking and working in a fearless atmosphere.

• interest in enquiring and questioning.

• ability to reach conclusions after logical thinking.

• ability for manifest and establish freely the conclusions arrived at.

• interest for recognition in the society.

• determination to face the interference of society and make components whichis a part of social life.

When we consider the learning system, the domains to be stressed in educationaccording to the modern development becomes relevant.

The knowledge domain consists of

• Facts

• Ideas

• Laws

• The temporary conclusions and principles used presently by scientists.

The learning is a process. The continuous procedures we undergo to reach a particulargoal is process. The skills which are parts of the process to analyze the collected ideas andproofs and come to a conclusion is called process skills. Some important process skills are,the skills;

• To observe

• To collect data and record

• To classify

• To measure and prepare charts

• To experiment

• To predict

• To recognize and control the variables

• To raise questions

• To generalize

• To form a hypothesis and check.

• To conclude

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• To communicate

• To predict and infer

• To use tools.

Observation is the process of acquiring knowledge through the senses. It is purelyobjective oriented. Learning experiences which provide the use all the sense may be used.

The process of grouping is known as classifying. Starting from simple groupings ofdata, it can extend to the level of classification into minute sub-groups.

In addition to this, consider the skills related to creative domain also, they are skills:

• To visualize

• To connect facts and ideas in new ways.

• To find out new and uncommon uses of objects

• To fantasize

• To dream

• To develop creative isolated thoughts

Creativity is an essential component of process and activities. The element of creativityis involved in finding out problems, formation of hypothesis, finding 'solutions' to problemsetc. Through activity oriented learning experiences, opportunities to express creativity canbe created.

Again, the following factors consisting in the Attitudinal domain are also importantas;

• Self confidence

• Love for scientific knowledge

• Attitude to know and value history

• Respect human emotions

• Decide with reasonable present problems

• Take logical decisions ragarding personal values

'Hypothesis' is a temporary conclusion drawn using insight. Based on knowledgeand experiences relating to the problems the causes and solutions can be guessed.

As regards the application domain the important factors are the ability to:

• observe in daily life examples of ideas acquired.

• take the help of scientific process to solve the problems of daily life.

• choose a scientific life style

• connect the ideas acquired with other subjects.

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• integrate the subjects with other subjects.

Some basic stands have to be taken on the new scientific knowledge about intelligencelearning and teaching. When such basic concepts are accepted changes are required in thefollowing factors.

• The vision, approach, structure and content of the curriculum.

• The vision, approach, structure and content of the textbooks.

• Role of the teacher and the learner.

• Learner atmosphere, learning materials and learning techniques.

Some scientific perspectives accepted by modem world in educational psychologyare given below.

Constructivism

This approach puts forward the concept that the learner constructs knowledge. Newknowledge is constructed when ideas are examined and practiced in new situations relatingthem with the previously acquired knowledge and experience. That is assimilated into thecognitive structure of one's knowledge. This method which gives priority to critical thinkingand problem solving provides opportunity for self motivated learning.

Social' Constructivism

Social constructivism is a sub section of constructivism. Knowledge is formed, spreadand imbibed and it becomes relevant in a social environment. Interactive learning, grouplearning, co-operative participatory learning, all these are concepts put forward by socialconstructivism.

The main propounders of constructivism are Piaget, Vygotsky and Bruner.

Discovery learning and interactive learning have prime importance. Learning takesplace as a part of the attempt for problem solving. The activities of a learner who confrontscognitive disequilibrium in a learning situation when he tries to overcome it leades to therenewal of cognitive structure. it is through this process construction of new knowledgeand the assimilation of them take place. Observation and enquiry are unavoidable factors.The learner advances towards new areas of acquisition of knowledge where he tries tocompare his new findings with the existing concepts.

Learning is a live mental process. Rather than the ability for memorization of factscognitive process has to be given emphasis. The process of problem analysis, elucidation,critical thinking, rational thinking, finding out co-relation, prediction, hypothesis formation,application, probing for other possibilities, extracting the crux and other processes are ofcritical importance in learning.

Constructivism gives greater predominance to co-operative learning. Social andcultural factors influence learning. Sharing of knowledge and experience among learners,

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collective enquiry, assessment and improvement, group activity and collaborative learningby sharing responsibilities with the objective of public activity, provide opportunity foreffective learning.

In learning internal motivation is more important than external motivation. The learnershould have interest and initiative in learning. Learning situation should be capable offorming a sense of ownership in the learner regarding the learning process.

Learning is not a linear process. It progresses in a spiraled way advancing deeperand wider.

New concepts of Learning

1. Discovery Learning

The teacher has to create a motivating atmosphere for the learner to discover conceptsand facts, instead of listening always. Creating occasion to progress towards discovery ispreferred. Instead of telling everything before and compelling to initiate the models,situations are to be created to help the children act models as themselves.

2. Learning by discussion

Discussion leads to learn is Burner's theory. Here discussion is not opposing eachother. It is a sharing on the plane of ideas. New ideas are arrived at by seeking explanations,by mutual giving and taking of ideas and by problem solving.

3. Problem solving and learning

Only when the learner feels that some thing is a problem to be solved that he takesthe responsibility of learning it. It is an inborn tendency to act to solve a problem thatcauses cognitive disequilibrium in a particular area. It is also needed to have confidencethat one is capable of doing it. The problems are to be presented in consideration of theability and level of attainment of the learner.

4. Collaborative learning

This is the learning in which the responsibilities are distributed among the membersof the group keeping common learning objectives. The common responsibility of the groupwill be successful only if each member discharges his duties. All the members will reach astage of sharing the result of learning, equally through the activity with mutual understanding.The teachers who arrange collaborative learning will have to make clear the responsibilitiesto be discharged. This is possible through the discussion with the learners. Collaborativelearning will help to avoid the situations of one person working for the whole group.

5. Co-operative learning

This is the learning in which the learners help one another. Those who have moreknowledge, experience and competency, will help others. By this exchange of resourcesthe learners develop a plane of social system in learning also. As there are no high ups and

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low ones according to status among the learners they can ask the fellow learners doubtsand for helps without any hesitation or in hesitation Care should be taken not to lead thisseeking of help to mechanical copying. It should be on the basis of actual needs. So evenwhile encouraging this exchange of ideas, among the members of the group cautiousacceptance is to be observed as a convention. There should be an understanding thatsatisfactory responses should come from each member and that the achievement of thegroup will be assessed on the basis of the achievement of all the members

6 Zone of Proximal Development

Vygotsky observes that there is a stage of achievement where a learner can reach byhimself and another higher zone where he can reach with the help of his teachers and peersand elders. Even though some can fulfill the learning activity by themselves there is thepossibility of a higher excellence. If appropriate help is forth covering every learner canbetter himself.

7 Scaffolding

It is natural that the learner may not be able to complete his work if he does not getsupport at the proper-time-The learner may require the help of the teacher in several learningactivities. Here helping means to make the learner complete the activity taking responsibilityby himself. The teacher has to keep in mind the objective of enabling the learner to take theresponsibility and to make it successful.

8. Learning an active mental process

Learning being a cognitive process, the teacher needs to know cognitive processesto facilitate the creation of learning opportunities. Learning can be made effective byproviding learning experiences involving mental processes like

• Retrieves/recollects/retells information

• Readily makes connections to new information based on past experiences andformulates initial ideas /concepts.

• Detects similarities and differences

• Classifies/categorise/organizes information approximately.

• Translates/transfer knowledge or understanding and applies them in a newsituation.

• Establishes cause-effect relationships

• Makes connections/relates prior knowledge to new information/applies reasoningand draw inferences

• Communicates knowledge/understanding through different media.

• Imagines/fantasises/designs/predicts based on received information

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• Judges /appraises/evaluates the merits or demerits of an idea/develops ownsolutions to a problem.

9. Intrinsic Motivation

Intrinsic motivation is given more importance than extrinsic motivation. The teacherhas to arouse the internal motivation of the learner. A person internally motivated alonecan immerse in learning and own its responsibility.

A unified approach to multiple intelligence

Components of intelligence

1. Verbal/Linguistic intelligence

The ability for reading, writing, verbal production speak and communicate effectivelybelong to this type. This type of intelligence can be developed through activities such asoral communication, report writing etc.

2. Logical/Mathematical intelligence.

Abilities like logical thinking and finding out patterns and relations belong to thiscomponent. This type of intelligence developed through establishing relationships andmathematical operations.

3. Visual/Spatial intelligence

People with prominently visual/spatial intelligence will be able to design models andexecute ideas they have. Architects, designers and sculptures will be strong in this type ofintelligence. Model building, making of art material, painting and drawing will help thiscomponent develop.

4. Bodily/ Kinesthetic intelligence.

This intelligence is related to the ability to move the body parts. Dancers, actors andsports people who can move the body aesthetically and express emotions through bodymovements belong to this category. Activities involving Dance, aerobic, sports and gameshelp the development of this type of intelligence.

5. Musical intelligence.

It is believed that this type of intelligence is highly developed in people with theability to distinguish the different elements in music, performing musicians and those whocan appreciate music. Playing musical instruments, singing along with others, keepingrhythm etc are activities that help the development of this component.

6. Interpersonal intelligence

People who demonstrate leadership qualities and are able to interact in a positiveway with others will have a better developed interpersonal intelligence. They can understand

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the thinking of others and can successfully involve in negotiation activities. Role play andgroup activities can be used to cultivate this intelligence.

7. Intrapersonal Intelligence

This is the ability to understand oneself. These people can recognize their own abilitiesand disabilities. Writing diaries truthfully and in an analyzing way and assessing the ideasand activities of others will help developing this areas of intelligence

8. Naturalistic Intelligence

A great interest in the flora and fauna of the nature, love towards fellow beings interestin spiritual and natural factors will be capable of developing this area.

9. Existential Intelligence

The ability to see and distinguish ours own existence as a part of the universe, abilityto distinguish the meaning and meaninglessness of life, the ability to realize the ultimatenature of mental and physical existences, all these re the peculiarities of this faculty ofintelligence.

Emotional Intelligence

The concept of emotional intelligence put forward by Daniel Golman was used inframing the new curriculum. The fact that one's Emotional Quotient (E.Q) is the greatestfactor affecting success in life is now widely accepted. The teacher who aims to focus onimproving the emotional intelligence of learners need to concentrate on the following.

i) Ability to take decisions

Rather than imposing decision on learners while planning and executing activities,the learners may be allowed to take part in the decision making process. Taking decisionsthrough open discussion in the class, inviting learners suggestions on common problemsetc. are habits to be cultivated.

ii) Ability to reach consensus

• When different opinions, ideas and positions arise, the learners may be giventhe responsibility to reach a consensus.

• Imagining what would be the course of action in some situtations, allowing tointervene in a healthy way in problems between individuals.

iii) Problem solving

• Developing the idea that there is reason and solution to any problem.

• Training in finding reasons for problems.

• Suggesting solutions through individual or group efforts.

• Discussing social problems.

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• Analyzing the shortcomings in methods to solve problems.

Whether plastic can be banned within school premises can be given as a problem.Group discussion will provide reasons and solutions. Problems which can influenceclassroom learning and for which the learner can actively contribute solution need to beposed

• Self criticism, evaluation

• Ability to face problem-situation in life

• Thinking what one would do if placed in the situation of others, how one wouldrespond to certain experiences of others - All these foster the growth of emotionalintelligence.

iv) Life skills

Life skills need to be given a prominent place in education. W.H.O. has listed : skillsrequired for-success in life.

• Self awareness

• Empathy

• Inter personal relations

• Communication

• Critical thinking

• Creative thinking

• Decision making

• Problem solving

• Coping with emotion

• Coping with stress

The new curriculum addresses these areas.

Knowing the characteristics of the learner, role of the teacher and how to use theteachers handbook help the teacher to plan and effectively implement learning activities.

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Role of a Vocational TeacherIn the earlier approach the teacher was mainly depending on the lecture method for

teaching. But in the new method of education the learner centered approach in given moreimportance than the teacher centered approach. Under this changed scenario the vocationalteacher has to perform the following roles in the classroom.

The Vocational teacher should be

• A facilitator of learning

• A guide to the overall development of the learner

• A good observer and motivator

• Able to consider the activities, needs, special features and age group of learnersat higher secondary level.

• Able to understand the limitations of learner and their learning problems.

• An instructional material developers

• A good communicator

• An innovator

• Able to raise leadership qualities and self confidence of the learner

• An authoritarian in the concerned subject

• Able to arrest and sustain the attention of the learner

• Able to bring out and encourage the inborn talents.

• A resource manger to ensure the optimum utilization of resources.

• A systematic record keeper

• A counselor to issue guidance to the learner.

• A person with high level of practical competency

• Able to correlate area of study with familiar environmental situations

• A self evaluator and good listener

• Able to create awareness in social problems

• A person with democratic and humanitarian approach

• A professionalist as well as philosopher

• A good evaluator

• A good organizer and a friend.

• A co-learner as well as co-researcher

• Able to give assistance and advice in placement needs and self employment bygiving moral and technical support

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• Able to keep moral values

• A person equipped with skill for using new techniques of learning

• Optimistic and impartial

Child friendly Class Room Atmosphere

Learning can be effective and enjoyable only when the class atmosphere is accordingto the new conception of learning and the characteristics of higher secondary learner.

• Class and seating are arranged in an attractive way

• Democratic nature is upheld

• Always active

• Learners interact with teachers without fear

• Opportunity for a variety of activities

• Learners allowed to involve interesting group activities

• Learning speed, learning style and differencing levels of attitudes are considered.Help is extended whenever needed.

• Sufficient instructional materials are available

• There is freedom of expression, learners share their ideas and experiences

• Learners are given acceptance and encouragement

• Healthy atmosphere

• Needs of each learner is given consideration. Happy and energetic atmosphere

• Teachers work considering the rights of learners

• Problems handled in a patient way

• Teachers work at all events from the learners view point

There will be learners of various ability levels in every class because learning style,learning speed, varying exposure to language experiences, physical and psychologicalproblems and varying socio-cultural background.

The learning experiences provided must help to bring the low activities to an expectedlevel and extended the breadth and depth of the skills of the high activities.

By repeating experiences, introducing variations in a learning experience to suitdifferent levels and if needed, formulating additional experiences the problem of varyingability levels can be tackled.

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Role of Learner

The learner in second year has undergone a learner centered and process orientedlearning experience up to first year. The learner at this age is in awakening stage and he isenthusiastic about environment. He needs recognition and encouragement from environmentand also recognize as a grown up man. He is adequately competent to select vocationalsubjects according to his aptitude and interest and to acquire higher education and professionas he wishes. The aspirations about future life is framed in this particular age for seemingnational and international job opportunities. Some of the peculiarities of learner at thisstage are;

• Physical, intellectual and emotional changes are intensive during the age andtheir reflections can be observed

• Ability to enquire discover and establish cause effect relationship betweenphenomena

• Readiness to undertake challenges

• Capacity to shoulder leadership roles

• Attempt to interpret oneself

• Susceptibility to different pressures

• Doubts, anxieties and eagerness about sex

• Imaging for social recognition

• Active participant in the learning process

• Act as a researcher

• Sharer of information

• Sharer of responsibilities

• Collect information

• Jakes leadership

• Involves in group work

• Act as a co-participant

• Observes his environment

• Experiments and realize

• Make interpretations and draw inferences

• Mould himself in to an active contributor for the welfare of the society

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Needs of Learner

• To make acquaintance with a job or self employment through vocationaleducation

• To acquire more knowledge in the concerned area through higher education

• To recognize and encourage the peculiar personality of the later adolescentperiod

• To enable him to defend against the unfavorable circumstances without anyhelp

Evaluation

In vocational higher secondary education, a new approach to education and evaluationshould be made. Evaluation must be a systematic and continuous process. As the curriculumis based on vocational stream, capacity building is a most important part and it should beevaluated accordingly. The technical skills, interest in the particular field, communicationskill, analysis organizing and presentation skills etc have to be evaluated. The personaland social qualities also have to be evaluated. Therefore, evaluation should be transparent,continuous and comprehensive.

Monitoring system

Education is a kind of journey from darkness to light satisfying the needs and thewants of the individual and the society. The modernization of education through activityoriented system enhances free thinking and working in a fearless atmosphere. It is aqualitative process not a quantitative one this necessitates a proper monitoring system. Thesystem of monitoring should have the following features.

1) It must be transparent

2) It must enrich the ideas of the facilitator through innovative process

3) It must be time bound and rational

4) It must motive the facilitator to adopt new strategies

5) It must be recordable and ensure effective feedback for the effective monitoringof the system, three levels of the mechanism should be setup.

1. School level monitoring group

2. Regional level monitoring group

3. State level monitoring group

Moreover a social auditing system is advisable to attain the objective effectively.

Supporting System

In learner centered vocational education, a learning methodology has to be organizedand a proper learning atmosphere is to be provided. Many organizations can support the

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learning activity. They are:-

1) School Resource Group (SRG)

Comprising all teachers (vocational and non vocational) instructors, and labassistants with academic head as the group leader.

2) School support Group (SSG)

Comprising PTA president, members of local bodies, members of social clubs,subject experts etc who can contribute guidance /technology /infrastructure /financial assistance etc.

3) Parent Teacher Association (PTA)

Can provide adequate funds for field trips, production cum training centers(PCTC), exhibition, On Job training (OJT) etc.

4) Local bodies

Grama Panchayat, district panchayat and block panchayat can provideinfrastructure ie, class rooms, laboratory, library, seminar hall, audiovisualequipment etc.

5) Subject club

All vocational teachers handling same vocational subjects should form a subjectclub at regional level or district level. This will helps to share the knowledgeand practical facilities, production and marketing of materials, service etc.

6) Based on the excellency, district wise nodal schools may be selected to providefacilities like central library, museums, video conferencing etc.

7) Institution Industry Interaction Project (III P)

This should be implemented in every institution to update knowledge this alsohelps for OJT , PCTC and field visit.

Features of learning process in the new system of education

In the new system of education the learning process should be modified in such away as to enable the learner to construct the knowledge of his own through observation,co-operation, problem solving, social interaction etc. The learning process should considerthe nature ability, social setup, inborn talents and subject selected by the learner. Thereforethe learning process should be,

• A continuous mental process

• Simple - learner must feel that he is able to undertake the task

• Enable the learner to attain the curriculum objective

• Interesting

• Suitable to the age and attitude of the learner

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• Future possibilities

• Enable group activity

• Challenging

• Time bound

• Constructive and curiosity developing

• Possibilities for evaluation

• Capacity to generate independent thinking

• Ability to enquire discovers and establish cause effect relationship betweenphenomena.

Learning Aids

To make the teaching and learning process simple and effective, certain learning aidsand necessary use of such aids are transacting a complex idea makes the class room liveand learners get more and more involved. The advancement of science and technologymay be effectively utilized for this purpose. Some of the learning aids listed below.

• Multimedia

• Over Head Projector

• Computer

• Internet

• Liquid Crystal display Projector

• TV, VCD, DVD and tape recorders

• Working models

• Charts

• Slides

• Video Conferencing facility

• Library

• Text book

• Source book

Society

The new educational policy uplifts the social commitment of the learner. Thereforethe society can also give some valuable contributions in this changing situation. The newsystem also ensures that the learner can perform certain useful services for the bettermentof society. The social obligations can be illustrated as follows.

• To enrich social values, aptitude and ability in learner

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• To develop entrepreneurial aptitude and ability which helps social welfare andself employment

• New system of education adopts OJT, PSTC etc as a part of vocationalcurriculum which helps to make close contact with the society.

• The resources available from our society can be positively utilized to conveneseminars, interview etc.

• Social organizations can help learners to make their education sociallycommitted.

• The social clubs like NSS, Tourism club, Eco club, energy club etc functioningin schools can make direct link with the society.

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SUBJECT APPROACH

Introduction

The eternal search of the mankind for better living conditions and comfort has forceda radical revolution in the field of science and technology. Starting from the invention ofwheels, it has passed through many stages and steps to enter into the era of computers andinformation technology. Though the progress was steady and gradual at the initial stages,non in the modern times, when the world is dashing from electronics to photonics, thedevelopments has acquired an unimaginable pace and depth. Neverthless to say, for anyone who glimpses around these changes it is very clear and factual that electronics servesthe foundation for most of these developments. No matter, if it is simple calculator or ahighly sophisticated space craft. This undebatable relevance of electronics in the modernworld has ofcourse paved the way for the creation of a large number of opportunities in therelated fields.

In this context, the vocational higher secondary course in MRRTV is so designed asto enable the learner to develop the necessary skills to establish himself as a prominantservice technician in this field. With this concept in mind, the subject is given a cleanorientation towards practical applications. Any how theoretical explanations and hypothesisare supplemented when and where required.

Curriculum Objectives

l To familiarise the learner with the types modulation and modulators.

l To develop basic idea about AM and FM Radio transmitters and thecorresponding receivers.

l To understand the function of various audio equipments like Audio taperecorder, PA system, CD player, MP3, Dolby system, etc..

l To develop the basics behind Television transmission.

l To create awareness about the various sections of a monochrome receiver andits trouble shooting.

l To create awareness about the basics of a colour TV transmission.

l To create awareness about the various sections of a colour TV receiver and itstrouble shooting.

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l To create awareness about the various video equipments such as VCR/VCP,VCD player, DVD player, Digital Camera, etc.

l To familiarise the learners with the working of TV Tuner Card.

l To familiarise the learners with the satellite communication system.

l To familiarise with digital receiver (DTH) and its trouble shooting.

l To obtain clear idea about the working of CATV and CCTV.

l To develop basic idea about EDUSAT.

l To develop basic idea about the modern television technologies such as HDTV,OLED TV, Mobile TV, Plasma TV etc.

In brief the curriculum is framed to achieve the objective of equipping the learner todevelop the skills for servicing different electronic equipments such as radio, television,taperecorder, music systems, VCD, DVD, DTH etc. based on the sound knowledge of thebasic theories, components, devices and circuits acquired in the previous year.

Contents of the Course

Syllabus

1. Radio Communication

Modulation and Demodulation: Modulation, Need for modulation types of modulation-AM and FM modulating circuits. Demodulators (simple circuits only).

Radio Transmitters : Basic accepts of radio transmission and propagation. AM radiotransmitter, FM radio transmitter -block diagram.

Radio Receivers : AM Radio receiver- introduction, super heterodyne receiver -block diagram, controls, Typical faults and remedies. FM.

Radio receiver -introduction, block diagram, controls, typical faults and remedies.

2. Audio Equipments

Audio tape recorder (Mono and Stereo) - Introduction, block diagram, controls,typical faults and remedies - Public Address system- Introduction, block diagram,trouble shooting - CD Player- Introduction, block diagram, MP3 system, Dolbysystem, DTS (basic treatment only.

3. Television Transmission

Introduction, aspect ratio, scanning, interlaced scanning, TV camera tube (vidicon),composite video signa, negative modulation, VSB transmission, intereference, TVtransmission standards, television transmitter - Block diagram.

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4. Monochrome Television Receiver

Introduction, block diagram-explanation, RF section, IF section, Video detector, Syncsection, Horizontal and vertical section, AGC & AFC, Sound section, Power supplyand EHT. User antenna and transmission lines trouble shooting of different stages.

5. Colour TV Receiver

Introduction, compatibility, colour fundamentals, colour mixing, luminance andchrominance signal, colour difference signals, colour synchronization and burst, colourcomposite video signal, colour TV system-NTSC, PAL, SECAM (Basic Conceptonly). PAL colour receiver Block diagram description. User and technician controls,PIL colour picture tube schematic diagram, convergence and purify basic idea,pincushion distortion, Automatic degaussing, trouble shooting in colour TV receivers.Remote control-Basic principle.

6. Video Equipments

• Video cassette player / recorder - Introduction,

• Basic principle, VCD player - Block diagram,

• Working, controls, trouble shooting. DVD player (Basic concept only)

• Digital camera - Introduction and basic concept

• TV Tuner card - Introduction

7. Satellite Communication

Introduction, satellite communication system, transponders, digital transmission-basicprinciple, dish antenna, satellite receiver DTH-block diagram, working,accessories(splitter, connector, repeater) trouble shooting (able TV & closed circuitTV-basic principle) working, application, educate Introduction, application.

8. Advances in Television Technology

1. Plasma Television, LCD Television, Project Television

2. Mobile television, OLED Television, High Definition

3. Television (HDTV) Hollo graphic Television

4. DLP (Basic concepts only)

Learning Approach

Any modern curriculum visualises learning as a continuous and smooth processleading to a behavioural change in the learner. In that sense, the learner himself is thecreator of knowledge. Real knowledge is a result of factual experiences and is cementedthrough activities in which the learner should be the main participant. As far as learning of

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technical subjects are concerned, this is more significant. Because only that knowledgeacquired through real practical or working experience can be effectively applied to tackle aneedy situation.

In general the curriculum envisages to promote three basic qualifiers - multiple intelligence,constructivism and emotional quotient(E.Q) - of the learner. That is, the learning process shouldcontribute for the overall development of various facts of multiple intelligence such as linguisticintelligence, logical intelligence, visual intelligence, kinaesthetic (bodily) intelligence,interpersonal intelligence, intra-personal intelligence, musical intelligence and naturalisticintelligence of the learner. Secondly the various methods adopted for learing should be helpfulto develop the constructivism within the learner. Methods, like Inquiry learning, Problemsolving learning ........ etc are highly useful in this regard. Last but not the least important is theimprovement of the emotional quotient of the learner. Emotional quotient (E.Q) of a person isan indicator of his ability for decision making, problem solving, investigative thinking andinnovative approach which lead to the leadership qualities within him. The learning methodsshould enhance these qualifies and raise the E.Q of the learner.

Apart from above listed personal aspects, another significant factor that should beconsidered while framing a curriculum is the social impact on the outcome of the learningprocess. The knowledge and skill acquired by the learner must be contributive for the overalldevelopment of the society and should serve as a catalyst for the social development of theregion or area where he resides.

To achieve the above goals, the learning process must be compatable and flexible to facethe needs and necessities of that particular region. It should be always ready to lend the ears tocatch the beats of the social and economical environment prevailing there. That is why thevocational higher secondary course adopted a locally specific, participatory curriculum basedon a need analysis survey. To brief up, it can be emphattically said that, the successful completionof the course will help the learner to find his livelyhood from his own surrounds and will ensurea respectable identity within the society. Moreover, that will contribute, an enthusiastic, self-reliant model citizen who is always at will to care for others and D extend his services to hisfellow people, to the society.

Participatory Curriculum

Role of the teacher

(i) Facilitator- who encourage the students to identify the problems and to tackle themfruitfully.

(ii) Motivator- who motivates the students to accept challenges enthusiastically.(iii) Friend- who develops a sound relationship with the students in and outside the class-

room

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(iv) Leader- who is willing to share his views and impart his ideas while caring other’ssuggestions

(v) Resource Person- who is mastered in the subject and well-versed in the modern stratagiesof learning.

(vi) Scaffolder- who brings the students to the expected level of learning when they fail toachieve it by themselves.

(vii) Evaluator- who evaluates the performance of the students at different stages and motivatethem to try for better heights.

(viii) Co-learner- who is a co-learner in the constructive learning process.(ix) Researcher- who applies his own stratagies and skill to find solution for problems faced

by the learners.(x) Life time learner- who updates his knowledge time to time, polishes it through different

activities and tries to acquire more knowledge and skill always.

Role of the learner

(i) Enthusiastic participant in the learning process.(ii) Present innovative ideas of their own.(iii) Active participant in group activities.(iv) A nice co-participant.(v) Willing to share ideas and responsibilities.(vi) A good leader.(vii) A good observer and experimentalist.

Learning Atmosphere

For the effective implementation of the modern learning methods and stratagies, it isof paramount importance to setup the right atmosphere or environment for learning. Theenvironment should satisfy the physical, psychological and social requirements to attainthe desired results. A well-furnished class-room, well-equipped laboratory, a good library,a resource room, internet facilities, LCD and OHP projectors, a play ground, anauditorium...etc are some of physical requirements to create the right atmosphere.Psychological factors include the co-operation of the management, principal, teachers,students, parents and the society, a disciplined campus atmosphere and facilities forcounselling and guidance. The availability of academicians, industrial experts and otherresource persons, active support of the PTA, local bodies and social workers...etc are thesocial requirements for a good learning atmosphere.

Modern Learning Methods

According to the modern concept, the learning process will be more effective andfruitful if the following methods are adopted:

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(i) Problem solving method – Experimentation in the lab, project,assignments.....etc

(ii) Discovery learning method - Project, Feild visit, Assignment

(iii) Co-operative learning method - Group discussion, Debate, Seminar

(iv) Inquiry learning method - Survey, Reference work in library or internetreports...etc

(v) Collaborative learning method - Group discussion or analysis.

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LEARNING STRATEGIES

In the modern era of globalization the introduction of new technologies ensure onlythe survival of the fittest. So it becomes a necessity to equip the leanness to face the growingchallenges in the competitive world. Hence the traditional approach to learning is no morerelevant in the present context. The teacher should use instructional techniques that motivatethe learner to construct his own knowledge. Now the learners are not passive listeners, butthey are the active participants in the construction of knowledge. Here the teacher - learnerinteraction should be given much importance.

In the new instructional strategy while selecting the methods of teaching, the socialand psychological aspects of the learner is to be taken into consideration. The given activitiesfor learning are only suggested one. It can be altered according to the discretion of theteacher.

To obtain the objectives, the new system of education is introduced in the VocationalHigher Secondary Education for attaining the objectives of the courses in this system, wecan adopt the following strategies.

1. Assignment

Assignment is some specific work assigned to the learners as a part of their academicenrichment. There are learning activities undertaken as a continuation of class room activitiesto realize the curriculum objectives to a broader extent. They should be completed in timebound manner. They help to lead learner to higher level of learning from the present status.Challenging assignment can motivate the learners to involve in group dynamics and achievefruitful results. The teachers may act as a guide.

Assignment may be given on individually or on group basis. Assignment includespreparation of notes, preparation of charts, models, collection, of materials from institutionsetc. Assignment develop skills of reference, observation, enquire reporting etc. It ensurethe effective utilization of leisure time of the learners.

2. Seminar

Seminar is a learning strategy involving an in-depth analysis of specific topic,preparation of a paper and presentation. The paper is presented by either one learner or a

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group of learners. After the presentation, there will be a discussion/ interaction in which allthe learners can participate. The learners get an opportunity to clear their doubts and makeclarification. Seminar helps to develop communication skill and overcome stage fright.

Stages

1. Selection of Topic

The topic of seminar should be relevant to the subject of study

2. Assignment of topic to individuals learners or team

The topic may be assigned to each learner or subtopics may be given to agroup of learners

3. Collection of relevant information

Information required for seminar can be collected from various sources namelybooks, magazines, internet, institutions, place and persons.

4. Preparation of draft paper

Based on the information collected the learner may prepare a draft paper andsubmit it to the teachers for comments. Revise the draft paper based on thecomments of the teachers. The required draft is submitted for approval.

5. Program Scheduling

The date, time and venue of the seminar is fixed. A seminar leader may beselected from the learners

6. Seminar paper presentation

The learner/ learners shall present the paper in the seminar. The teacher mayfunction as the moderator during the initial stages.

7. Discussion / Interaction

A number of respondents from the learners make comments on the topic. Thiswill be followed by a general discussion. All the group members should activelyparticipate in discussion.

8. Summing up deliberation

The moderator sums up the deliberation

9. Evaluation / Feed back

Both teachers and learners evaluate the programme.

10. Preparation of final report

A final seminar report is prepared covering all the additional points discussedand consolidated.

3. Panel Discussion

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It is a learning strategy in which a panel of experts are allowed to discuss a specificsubjects under the control and direction of a moderator. Subjects can be divided accordingto the number of panel members. Number of panel members are fixed according tosubdivision of points in the subject. Relevant materials and hand out may be given inadvance to the learners. The monitor or moderator introduces the subject of discussion andinvite a panel member to start the discussion. Each panel member is invited for discussionafterwards. After briefing by the panel members the question are raised from the audienceand the panel members give suitable answer to them. A report should be submitted by eachlearner to the moderator.

4. Project

Project is a self-learning strategy which can exert great influence on the overalldevelopment of the learner. Project as learning strategy is to be selected where a problemarises in any part of the curriculum. The learners may be divided into groups and assigneddifferent aspects of the problem. Each group works independently .Specific aspects of theproblem such as data collection, classification, analysis, report preparation and presentationis to be undertaken by each of the members. Even though the work is divided among themembers, it must be ensured that the execution of each and every activity is done with theactive participation of all. After analyzing data collected from different sources, the learnerarrives at a conclusion, which helps to solve the problem. There by learner learns the topicthough his own activity. The other advantage of this learning activities is that it helps thelearner to scientifically handle any problematic situation. It helps in the development ofscientific thinking and thereby builds up the learners aptitude for the subject.

Stages of the project

1. Selection of a topic

The project selected should be related to the curriculum and it should not be aproject for projects sake. The topic or problem should arise from the curriculum.

2. Planning of the Project

(A) Hypothesizing: Hypothesizing means making assumptions based on theavailable primary information.

(B) Methods and Techniques : The methods and technique should be based on theaim and Hypothesizing of the project. The nature of the project, suitability ofthe tools, and the methods of learning should be related to each other.

3. Collection and Tabulation of Data

The data may be primary, Secondary or teritiary. Either census or sambling methodcan be used based on the objective of the project. Suitable questionnaires are to be preparedfor the collection of primary data.

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The collected data is to be classified and tabulated so as to make it easilyunderstandable.

4. Analysis of data and formulation of conclusion

By analyzing the data, the reliability of the hypotheses can be examined. Preparationof graphs and diagrams and maps will positively help the analysis. The similarities relationsand differences gathered from the analyzed information would tell whether the hypothesesshould be accepted or rejected.

5. Preparation of Report

The cover page should have the title of the project, the period of study, name (s) ofinvestigator / group, and the address of the school. The report should be structured in thefollowing order.

1. Title

2. Preface

3. Hypotheses and aim

4. Methodology

5. Sources of data

6. Analysis and conclusion

7. Suggestions (if any)

8. References

9. Appendices (Questionnaire, Observation schedule, check list Etc.)

6. Presentation of the Project

When the project is presented, the learner is being evaluated and accepted. Duringpresentation ideas are shared with others. The project method promotes scientific selflearning and makes him capable of solving the problem arising in real life situations.

5. Debate

Debate is a hot and interesting learning activity. A debate can be organized only ona topic on which there is difference of opinion. Therefore a topic suitable for debate has tobe found.

Debate can be on relevant topic that is different and interesting to the learners andrelevant to society. Learners with different opinion have to be identified for discussion.Those who have similar opinion should join together to form a side. Those who hold theopposite view with form the other side. It would be good to write down the topic of thedebate and displayed in advance. There should also a person to control debate.

Learners should be given opportunity to absorb the ideas obtained from discussionand debate, develop the idea through reading and study, and to express them through

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writing or other means

Stages of Debate

1. Topic Selection

2. Selection of panels keeping in balance with intelligence, gender etc.

3. Selection of moderator

4. Collection of information guided by the teacher

5. Conducting the debate under the control of moderator by avoiding any sort ofpersonal conflicts

6. Conclusion by the moderator expressing his final version or verdict.

6. Case Study

A case may be a person, institution or a community case study is an in depth analysisof an actual event or situation. It presents real pictures of situation with facts, objectiveinformation or data learners analyse the case to interpret, predict and resolve issues associatedwith it. The case study provides the learner an opportunity to analyse and apply concepts,data and theory taught from the class. Learners can work individually or in groups.

By studying realistic cases in the classroom, learners develop new insights into thesolution of specific on - the - job problem and also acquire knowledge of the latest conceptsand principles used in problem solving.

Case may be presented by the teachers or may be provided in print form.

A simple case study may have the following steps

1. collection of data

2. Conversion of data into information

3. Analysis of the case in groups

4. Presentation of the finding by each group leader.

5. Evaluation

In addition to the above mentioned learning strategies there are many other learningstrategies which can be used in appropriate situations to enrich learning process such asProblem solving, Role play, Brain storming, etc

7. Brain Storming

This is the best method for solving creative problems. It facilitates generation ofideas quickly. Rules for conducting Brain storming.

1. No response is wrong - welcome every response.

2. Welcome as many responses as possible

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3. No criticism is allowed

4. allow to work on others idea

Steps in Brain storming

1. Presentation of the problem

2. Provide relevant information

3. Record the ideas put forth by the participants

4. Combine similar ideas

5. Evaluate each idea and solution

6. Selection of the best solution

If brainstorming is used as an instruction strategy, the last step is not essential

8. Discussion

Discussion is essential for the learner to share new finding, ideas and conclusion ateach stage of learning with follow learners and teachers. In general discussion the teachersshould guide the discussion though questioning and summarizing. The major steps involvedare

1. Introduction initiated by the teacher

2. Development of discussion by giving lead points and follow up interactions

3. Transaction stage in which the key points are reviewed by the teacher and

4. Summarizing stage in which teacher provides additional support materials toensure the achievement of the objectives

9. Group Discussion

Group discussion is an ideal method to develop Co-operation, democratic attitude,friendliness and compromising attitude which are the ultimate aims of education. Duringgroup discussion the teacher may observe each group and it needed help them to channellisethe discussion towards the common objectives. All learners may be given opportunity totake part and express their ideas within a time limit. The conclusion reached may beentered by each learners. A group representative must present this during consolidation inwhich the teacher may correct or add information's to ensure that all the relevant ideashave been covered

10. Collection

Collection is a continuous learning activity, which ensure complete participation oflearners. The collected item may be materials, pictures, charts, ideas, data etc. Collectionprovides direct experience to learn. An exhibition of collected materials will help to strengthenthe concept.

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11. Practical works

Experimentation contains the process skill in an integrated way. In the new approachof curriculum the learner forms idea and comes to conclusion though process. The term'Practical 'when associated with a science subject usually means an experiment. Theobjective of doing an experiment is to explore new ideas through investigation only. Itsmain purpose is to verify some principles associated with theory. The relevance of 'practical'in the traditional science subjects ends here. But this is not the case with 'Vocational Practical'

The ultimate goal of a Vocational Education is to generate skill through continuouspractice along with investigation and invention. Continuous practice transforms the unskilledto the skilled. This is the significance and importance of practical in the Vocational stream.Hence it is very crucial that Vocational teachers as well as instructor should understand theimportance of vocational practical and act accordingly.

10. Quiz

Quiz programmes can be used as an interesting class room tool for transaction ofcurriculum objectives as well as to evaluate the effectiveness of transaction and achievementof learners.

For conducting a quiz programme a topic should be selected based on the aboveobjective

The learners are asked to prepare question based on the topic individually. The nextday / next hour the learners are grouped into 3-4 groups randomly. A question is raised bya particular team and the other teams to answer them if they can answer the question theyget points for that if all other teams fail to answer the question raised by the 1St team the1st team answer the question and explain the background if necessary. All the teams getequal number of chance to ask the question . Time limit is also prescribed for the conductionof the programme. The team who scores maximum points wins

All the participants can make notes on the questions asked answer and theirexplanation which help them in learning

13. Models

Models are used in learning process. It enhanced the leaning experience. This isbased on the 'seeing is believing". It helps the learner a chance to see feel the model presented. Still models and working models help the learners to understand the structure , workingprinciples, actual operation etc.

Several steps are involved

1. Feeling the problem

2. The teacher should plan the type of model according to curricular objectives.

3. Grouping the learners

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4. Briefing the tasks- Aim

- Need

- Material required

- Source & Materials

- Cost of materials

- Division of Labour

- Guidance

- Fixing of a time limit

5. Presentation by each group about

(A) How the models were prepared

(B) Details of

- Expenses

- working and principles

Finally Documentation of the process

6. Evaluation

- By the other groups

Later a consolidation by teachers is to be done.

14. Games

Class rooms can be made attractive by introducing different types of games. Gamesshould be interesting as well as informative some of suitable games are

1. Odd man out

2. Cross word puzzles

3. Match the following

4. Aswamedham.

5. Link game - Answer using clues.

15. Survey

This strategy involves collection of data from the group under study (book, person,materials etc.) It develop the social interaction and communication ability of the learner. Italso provide a scope for discovery learning.

Step involved in survey

- Objective of survey

- Selection of area for survey/sampling frame

- Selection of survey method

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- Direct method

- With help of questionnaire/schedule

- Tabulation and analysis

- Considation and Presentation

16. Exhibition

It is a learning strategy by which the learner can get a chance to show the skilldeveloped. It provides the intrinsic motivation and exposure.

Exhibition item can be conducted either individually or as a group task. It can beconducted at school / Regional/State/National Level. Necessary publicity and otherarrangement can be provided. Presentation, documentation participation and innovativeskills of the learner can be evaluated.

17. Interview

Interview is one of the important learning strategies taking the help of a resourceperson. Interview is an inner view which provides opinion and information about a topic.

An interview is conducted by the following steps

1. How to introduce a problem?

2. Invite a resource person

3. Decide the questions by learners

4. Decide the time, place etc.

5. How to discuss

6. How many learners to participate

7. Implementation of the interview

8. Conclusion (Facilitator)

Items required

1. Interview Schedule

List of question prepared by learners Selection of learners, selected namessequence of question

18. Field Visit

Field visit is an inevitable vocational tool to be implemented in vocational HigherSecondary Education. This helps the learners to familarise with the modern technologiesand new situation in a different atmosphere. It provides learning though viewing. It isbased on the principle that seeing is better than having. It enables the learning to retain thelearned informations longer and to make the subject more interesting. It motivates and give

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more confidence in his/her particular vocation.

The facilitation should identify suitable center/ institution/site. Get prior permissionfrom the authorities before conducting the field visit. Give instructions to the learners forcollection data's/information's/materials/Specimens. Teacher may assign different dutiesto learners by working them different groups.

Each learner should take utmost care and interest during the visit. He/She shouldobserve and interact at the center/ institution where the field visit is conducted

After the visit, learner should acquire the ability to apply the ideas/concepts in hisfuture carrier. Each learner should submit a detailed repot about the field visit.

20. Demonstration

Though demonstration we can present an item/product and emphasis its features veryeffectively

Eg:- To understand the functioning of a computer

1. Material/Item/Process

2. Demonstration

3. Venue

4. Additional requirements depending upon the nature of the item

Demonstration Process

1. Introduction about the item/Material

2. Principles - Working

3. Operation

4. Components

5. Merits of the item

20. Chart display

It is also one of the important teaching aid. It can be used in every activities of alearning process.

Chart display is a written or pictorial representation of idea or concept. It is abbreviatebrief and clear. It is prepared by study

Benefits

1. A learner gets clear idea about the concept

2. The leaner can retain the ideas in his mind for longer periods

3. A complicated idea can be simplified though a chart

4. Cheap method of teaching aid.

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1. Radio Communication

Modulation and Demodulation: Modulation, Need for modulation types ofmodulation-AM and FM modulating circuits. Demodulators (simple circuits only).




2. Audio Equipments

Audio tape recorder (Mono and Stereo) - Introduction, block diagram, controls,typical faults and remedies - Public Address system- Introduction, block diagram,trouble shooting - CD Player- Introduction, block diagram, MP3 system, Dolbysystem, DTS (basic treatment only.

3. Television Transmission

Introduction, aspect ratio, scanning, interlaced scanning, TV camera tube (vidicon),composite video signa, negative modulation, VSB transmission, intereference, TVtransmission standards, television transmitter - Block diagram.

4. Monochrome Television Receiver

Introduction, block diagram-explanation, RF section, IF section, Video detector, Syncsection, Horizontal and vertical section, AGC & AFC, Sound section, Power supplyand EHT. User antenna and transmission lines trouble shooting of different stages.

5. Colour TV Receiver

Introduction, compatibility, colour fundamentals, colour mixing, luminance andchrominance signal, colour difference signals, colour synchronization and burst, colourcomposite video signal, colour TV system-NTSC, PAL, SECAM (Basic Conceptonly). PAL colour receiver Block diagram description. User and technician controls,PIL colour picture tube schematic diagram, convergence and purify basic idea,pincushion distortion, Automatic degaussing, trouble shooting in colour TV receivers.Remote control-Basic principle.

SYLLABUS

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6. Video Equipments

• Video cassette player / recorder - Introduction,

• Basic principle, VCD player - Block diagram,

• Working, controls, trouble shooting. DVD player (Basic concept only)

• Digital camera - Introduction and basic concept

• TV Tuner card - Introduction

7. Satellite Communication

Introduction, satellite communication system, transponders, digital transmission-basicprinciple, dish antenna, satellite receiver DTH-block diagram, working,accessories(splitter, connector, repeater) trouble shooting (able TV & closed circuitTV-basic principle) working, application, educate Introduction, application.

8. Advances in Television Technology

1. Plasma Television, LCD Television, Project Television

2. Mobile television, OLED Television, High Definition

3. Television (HDTV) Hollo graphic Television

4. DLP (Basic concepts only)

LIST OF PRACTICALS

1. Amplitude Modulator

2. AM Detector

3. Radio components Lay-out

4. Voltage data collection and tuning of radio receiver

5. Radio receiver- Fault finding

6. Tape recorder- Wiring diagram- PCB layout

7. Voltage data collection of tape recorder

8. Head adjustment (Azimuth Adjustment)

9. Tape Transport Mechanism

10. Fault finding in tape recorder

11. PA system installation

12. Identify and operate B&W TV controls

13. Identify and assemble a television antenna - Yagi Anteena

14. Tracing of power supply/SMPS stage of B/W TV receiver.

42


15. Mounting and testing the picture tube in the cabinet.

16. Tracing and fault finding of the horizontal sub section of a B & W TV receiver

17. Trouble shooting in horizontal output stage of a B&W TV receiver.

18. Trouble shooting in vertical section of a B&W TV receiver.

19. Trouble shooting in video amplifier stage of a B&W TV receiver.

20. Trouble shooting in sound section of B&W TV receiver.

21. Trouble shooting in VIF amplifier of B&W TV receiver.

22. Mounting and testing of VHF tuner.

23. Identify different stages and main components of colour TV.

24. Identify and test neck components of a colour picture tube

25. Tracing the SMPS stage of a colour TV receiver.

26. Identify controls and sockets of a color TV and tune program channels.

27. Identify tuner terminals and replace tuners

28. Tracing of videos IF amplifier section

29. Tracing sound section of a colour TV receiver.

30. Tracing Sync separators, AFC, and horizontal oscillator

31. Tracing horizontal output section.

32. Tracing vertical sweep section of a colour TV receiver.

33. Tracing of chroma section of colour television.

34. Tracing of video output section.

35. Identify the important parts in the tape path of VCR/VCP.

36. Identify the servo components in VCR/VCP.

37. Identify sensors and limit switches of a VCR/VCP.

38. General maintenance of VCR/VCP.

39. Identify and operate the controls of a compact disc player.

40. Identify different equipments and modules used in CATV system.

41. Installation of CCTV network.

42. Installation, tracking and trouble shooting of DTH receiver.

43. Installation of software and hardware of TV tuner card in computers.

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In the context of changing scenario in the field of education the role of teacher aswell as the role of learner has changed. The emerging needs of education evolved the roleof teacher as a facilitator. The learning process has been learner centered and activityoriented . Learning activities must enable the learner to develop process domain and multipleintelligence skill to its maximum extent. No matter whether these skills are attained insideor out side the classroom, teacher must be in mind that they are to be accomplished in time.In order to achieve this, the teacher must make necessary plans. The plan must be structuredas

Year plan, covering the entire activities for the whole year

Unit plan, which has to be prepared just before each unit.

Daily plan to provide activities for a day learning.

PLANNING

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• MRRTV

45

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• MRRTV

47

UNIT PLAN

Introduction

Unit plan is a specified plan of action of a unit. It will be in tune with activitiesassigned in the year plan. It also helps to arrange the learning and evaluation activitiessuitably to attain the curriculum objectives. In this source book a model unit plan issuggested. It tried to define the curriculum objectives of one unit, a few learning activitiesare proposed and the concept / idea / terms are also identified. In this unit plan the learningmaterial including reference books and website are also mentioned. It is only are also asuggested model, hence the teacher can modify learning activities according to the needand demand of the classroom environment and situations.

Sample Unit Plan

Name of teacher :

Name of School :

Subject : MRRTV

Unit : RADIO COMMUNICATION

Class : XII

Time :


• To create awareness about the basic principle of modulation and demodulationthrough general discussion followed by the presentation of the report

• To develop an idea of various reasons that makes modulation necessary inradio communication through classroom transaction

• To create a basic idea of different types of modulation (AM and FM) throughpreparation of chart.

• To create a basic idea of the working of a simple AM modulator circuit throughdemonstration and practical work in the laboratory.

• To create a basic idea about the working of a simple AM detector (diode) circuitthrough demonstration and practical work in the laboratory.

• To develop an idea about the working of an AM radio transmitter and familiarizewith its different section through field visit and preparation of chart.

48


• To develop an idea about the working of FM radio transmitter and familiarizewith its different sections by visiting nearby FM radio station and prepare areport.

• To refresh the basic concept of radio reception through group discussion andpresent the report.

• To introduce basic working principle of super heterodyne AM radio receiverthrough seminar and practical work

• To discuss the various faults and their remedies of AM radio receivers throughpanel discussion, practical work, typical case studies and prepare notes.

• To develop the idea of FM radio receiver through seminar and demonstrationand submit the report

• To discuss the various faults and remedies of FM radio receiver through paneldiscussion, typical case studies and prepare notes.

Syllabus

Modulation and Demodulation: Modulation, Need for modulation types of modulation-AM and FM modulating circuits. Demodulators (simple circuits only).




Content Specification• Modulation

• Need for modulation

• AM and FM

• AM transmitter

• Demodulation

• Super heterodyne radio receiver

• FM receiver

Learning Activities

• Discussion on modulation and demodulation

• Practical work on AM modulator and demodulator

• Chart preparation on AM and FM waves

• Field visit to AM and FM stations, to collect dates

• MRRTV

49

• Discussion on radio reception

• Seminar on FM radio receiver

Concepts / Ideas / Terms / Name

• Modulation

• Demodulation

• AM Modulator

• AM detector

• AM receiver

• FM receiver

• Propagation

• Super heterodyne principle

• If signal

Learning Materials

Chart, Reference book, Journals, Lab facilities, internet data

Output

Discussion note, Seminar report, Practical work recordings, Charts field visit report.

CE Items

Seminar

50


DAILY PLAN

Introduction

Daily plan is the systematic organization of the entire learning activities for eachperiod The activities designed should be appropriate to achieve curriculum objectives. Itincludes curriculum objectives, content specification, CE items and a list of essential learningmaterials. It can be prepared in two columns. The first column contains the learningactivities (process) and the second column for responses. Proper planning of lesson enhancesboth the learner and teacher to achieve the objectives.

Guidelines for preparing a daily plan based on learning

• Curriculum objective should be stated clearly.

• Include content specification.

• Learning activities should be appropriate to time, need of the learners, learningatmosphere and also considering the age of the learner.

• The teacher can club the period judiciously to get continuity in learning process.

• Individual participation should be ensured in the group activities and groupdiscussion.

• Learning activities should be challenging, interesting, live and thoughtprovoking.

• The teacher must motivate the learner by giving tips and clues in every stage oflearning process.

• Proper guidance explanations and relevant examples should be given whereverit is necessary.

• Evaluation questions may be asked to understand the level of comprehensionof the learner.

• Response part of the daily plan can be completed only after the execution ofthe classroom activity.

• Further planning should be based on this response.

• CE items and its activities should be given in detail.

• Special information, principles, ideas and concepts also be written separatelyin a box in the process column.

• Term evaluation questions may be written at the end of the daily plan.

• MRRTV

51

Sample Daily Plan

Name of the Teacher :

Unit : Radio communication

Topic : Modulation - need for modulation, AM, FM

Standard : XII

Strength :

Period : I hour

Date :


• To create awareness about basic principle of modulation and demodulationthrough general discussion followed by the presentation of the report /discussionnote.

• To develop an idea about various reasons that make modulation necessary inradio communication through classroom transaction.

• To create a basic idea about different types of modulations (AM and FM)through preparation of chart.

Content Specification

• Modulation

• Need for modulation

• Amplitude modulation (AM)

• Frequency modulation (FM)

Concept / Idea

Modulation, AM, FM

CE Items

Chart preparation

Learning Materials

Reference books, journals, internet data.

Output

Discussion note / Report

52


Response

• The grouping was effective.

• The response of group four was notsatisfactory.

• All other groups actively participatedand concluded in the main points.

Process

• Grouping the students in to five bynumbering.

• The groups are asked to discuss aboutthe terms modulation anddemodulation with some examplesby brushing up their previousknowledge.

• The groups are asked to preparediscussion notes and let them presentit.

• The teacher then consolidate thepoints

• The teacher should explain the needfor modulaton and the types ofmodulation.

• MRRTV

53

EVALUATION

Evaluation is a systematic process of collecting, analyzing, synthesizing andinterpreting evidences of learners' progress and achievements both in cognitive and non-cognitive areas of learning. Evaluation has to play significant role in making the learningprocess more effective. It provides diverse experiences to the learners, keeping in view theskill to be attained continuously by them.

As the curriculum is based on a particular vocation in the selected stream is the mostimportant part and it should be evaluated accordingly. Technical skills, interest and devotionin the field, communication skills, organizational and presentation skills are to be evaluated.Evaluation of the personal and social qualities also should be done. So the evaluationshould be continuous and comprehensive.

Terminal or Term End Evaluation (TE)

It is the written form of evaluation aimed at evaluating the facts, concepts and ideasgained by the learner. The test should not be aimed to evaluate the memory alone. Questionsare framed in such a way that the learners are able to apply different mental process whileanswering. The Terminal Evaluation questions give more emphasis on application, analysisand synthesis level.

The maximum scores for TE is 80 and the minimum is 24 (30%). The questionsshould be formulated taking into consideration the time required to read, think, understandsand write answers. These aspects should be considered while fixing the scores also. Toavoid blind guessing, multiple choice and application level questions may be mixed. Thetotal number of questions may vary from time to time. All the questions should be based onthe curricular objectives. Open ended questions but the choice questions also should bebased on the same curricular objectives.

Continuous and Comprehensive Evaluation (CCE)

Our traditional evaluation method measures only the memory and recollection capacityof the learner. To eliminate/ overcome the limitation the evaluation should be done onmulti dimensional ways by measuring multiple intellectual capacities of the learner. So it isbetter to evaluate the learner in a continuous and comprehensive manner. CCE helps thelearner to understand and develop adequate his own progress and to develop adequatestrategies for further improvement.

54


Merits

• Assess the all round development of the learner on a continuous basis througha variety of activities.

• Effective feed back is possible

• Remedial diagnostic teaching is possible

• Process as well as products are assessed.

A series of learning activities are grouped into five major thrust areas as follows

1) Investigative activities

Activities which create a spirit of enquiry, investigation and a mind for researchin the learner belongs to this group for example.

• Study project

• Case study

• Field study

2) Interactive activities

Activities which improve the communication skill, activities of sharing ideas,etc.

For eg:-

• Seminar

• Panel discussion

• Debate

• Group discussion

3) Assigned task

Activities assigned to the learners to enrich/ strengthen the concept and ideas.

For eg:-

• Assignment

• Collections

4) Performance task (Tests)

Activities related to the achievements of the learner.

For eg:-

• Class test (oral/ written/ performance test)

• Quiz

• Open book examination

• Interview

• MRRTV

55

• Group testing

5) Practical based activities line

• Preparation of working model

• Album

• Improvisation

From the above five group of activities, the teacher has the freedom to chooseany three areas for evaluation purpose.

1. Investigation Activity

1. Study Project

Sl.No Stages Criteria Score Total Scores

1. Planning

Relevance of the study Identification of problem Ability to select appropriate tools, ability to select suitable bearing method.

4/3/2/1

2. Data Collection Ability to collect sufficient and relevant data. Ability to classify and arrange data for analysis. Reliability and authenticity of the data collected.

4/3/2/1

3. Analysis and Inference

Ability to analyses the data Systematic arrangements. Ability to draw inferences based on analysis. Ability to give suggestions based on inference.

4/3/2/1

4. Report presentation Ability to present in logical and sequential order, authenticity of report, time bound completion.

4/3/2/1

5. Viva-Voice Knowledge of content and process. Ability to analyze data. Ability to justify inference. Ability to explain. Strategies and methods adopted.

4/3/2/1

56


Sl. Criteria ScoreNo.2. Case Study

Identifying the problem 4/3/2/1Approach to the problem 4/3/2/1Time bound Action 4/3/2/1Analysis of the problem 4/3/2/1Problem solving / Reporting 4/3/2/1

3. Field studyAttitude and readiness towards the taskCapacity for Observation 4/3/2/1Data collection 4/3/2/1Application of ideas 4/3/2/1Documentation / Recording 4/3/2/1

4. AssignmentAwareness of the contentComprehensiveness of the content 4/3/2/1Systematic and sequential arrangement 4/3/2/1Observation/suggestion/views/judgment/evaluation 4/3/2/1Timely Submission 4/3/2/1

5. SeminarPlanning and OrganizationCollection and data / content 4/3/2/1Observation / appraisal and clarity 4/3/2/1Content knowledge 4/3/2/1Presentation 4/3/2/1

6. Debate, Panel discussionReadiness to participate 4/3/2/1Depth of subject knowledge 4/3/2/1Communication skill 4/3/2/1Ability to justify the stand 4/3/2/1Presentation 4/3/2/1

7. Group DiscussionReadiness to participate 4/3/2/1Depth of subject knowledge 4/3/2/1Communication skill 4/3/2/1Ability to justify in a democratic way 4/3/2/1Leadership quality 4/3/2/1

8. InterviewPlanning Preparation of Questions 4/3/2/1Communication skill 4/3/2/1ParticipationReport preparation 4/3/2/1

9. CollectionCollection of materials/Documents 4/3/2/1Relevance and comprehensiveness 4/3/2/1Presentation 4/3/2/1Awareness of the content 4/3/2/1Time bound progress of work at each stage 4/3/2/1

10. QuizPreparation of questions 4/3/2/1Relevance of question 4/3/2/1Presentation 4/3/2/1Active participation 4/3/2/1Time management 4/3/2/1

• MRRTV

57

Practical Evaluation (PE)

The goal of vocational Education is to generate skills through continuous practicesalong with investigation and innovations. Continues and comprehensive practice transformsthe unskilled learner to a skilled one. This is the importance and significance of vocationalpracticals.

PE is done to evaluate the practical skills achieved by the learner in the concernedvocational subject Total Scores for PE is 150 and minimum is 60 score ie 40%. PracticalExamination is conducted for a batch of 8 learners having 6 hours duration.

Practical evaluation should be done taking into account the whole practicals includedin the curriculum since Learning of practical skills is a continuous process through out theperiod of study.

58


Vocational Competency Evaluation (VCE)

Vocational Competency Evaluation is to evaluates the vocational skill and aptitudedeveloped by the learners during the learning process. This is a system to judiciouslyevaluate the required value addition and consequent capacity building in the concernedvocational curriculum. The vocational education is aimed at developing interest, skills anddevotion in specific vocational fields. As other evaluation components like CE. PE andTE cannot assess the vocational competences and professional skills, acquired by the learnersan internship evaluation (IE) components has been introduced to meet this requirement.

Internship evaluation should be done based on the following components likeregularity and punctuality, value addition and capacity building.

1. Regularity and punctuality

Regularity and punctuality has vital role in vocational education learningcontinuous process, the regular presence of the Learner is must for attainingmaximum efficency.

2. Value Addition

Value addition is the qualitative measure of the learner's interest, devotionperseverance and efficiency. Value addition can be evaluated through conductingfield visits/ vocational survey. The experiences gained through field visit / vocationalsurvey increases the level of intrinsic motivation and positive attitude towards thevocational field and thereby increase his value as a semiprofessional.

3. Capacity Building

It gives a quantitative measure of the learner's skill in graded area exposure.Capacity building can be evaluated through conducting the following activities.

1. OJT / Simulated experiment

2. Performance - camp/exhibition/clinic

3. Performance - PCT/Service cum Training center.

These components help the learner to practice the acquired skills in the real situationand thereby increasing self-confidence and promoting self reliance.

Vocational Competency Evaluation Indicators

No. Items Scoe

1 Regularity and punctuality 10

2 Field visit / survey (anyone) vocational project 20

3 OJT/Simulated experiment performance - 20Camp/exhibition/clinicPerformance -PSCTC (anyone)/Practical skills

Total 50

• MRRTV

59

Regularity and punctuality can be assessed by using attendance of the learner andtime bound completion of tasks. It is evaluated by using 5 point grading system.

Rating scale

Sl.No Items 1 2 3 4 5

1. Regularity Never Often Usually Most of the time Always

regular regular regular regular regular

2. Puntuality Never Often Usually Most of the time Alwayspunctual punctual punctual punctual punctual

Item Evaluation indicators Scores ScoreEquality and punctuality 10Value addition Field visit

1. Attitude and readiness towards the task 4/3/2/12. Capacity for observation 4/3/2/13. Data collection 4/3/2/14. Application of ideas 4/3/2/15. Documentation/recording 4/3/2/1Or Survey1. Planning 4/3/2/12. Data collection 4/3/2/13. Consolidation of data and analysis 4/3/2/14. Drawing inference 4/3/2/15. Reporting 4/3/2/1 20

Capacity Building OJT/Simulated experiment1. Involvement/participation2. Skills in doing work/ communication skills3. Time bound action4. Capacity for observation, analysis and innovation5. Documentation, recording and display OrPerformance in camp/exhibition/clinic1. Ability for planning and organizing2. Mastery of subject3. Ability for communication4. Innovation5. Involvement/social commitment OrPerformance in production/service cumtraining center (PSCTC)1. Mastery of vocational skills2. Managerial capacity3. Promoting self confidence4. Innovation approach5. Promoting self reliance 20

60


Criteria for Promotion

l A minimum of 80% attendance is required to register for the public examination.Those who are having at least 65% can apply for condo nation from higherauthorities. Those who have shortage of attendance below 65% should re[eatthe second year.

l The learners should obtain minimum 30% score in all subjects separately inTE. In first year if the learner failed to obtain 30% minimum score in any subjecthe will be promoted and will be given chance for improvement.

l The learners should obtain a minimum of 40% score in the vocational practicalEvaluation (PE) that is 60 out 150 score. If a learner fails to attain the minimumrequired score for TE and secure minimum score for pass in TE, he need notreappear for practical examination and vice versa.

Consolidated forms of CE, TE, VCE and PE

• MRRTV

61

Sl. N

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62


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• MRRTV

63

Part- III Optional Subjects

20 60 20

Physics

Chemistry

20 80

Mathematics

English

General Foundation Course

Part- II Vocational Subjects

Vocational Theory

Vocational Practical

Vocational Competency

Subject

Part- I

Score Obtained Positional

Grade

Grade in wordsCE 20 TE

80PE150

IE50

Total

CE- Continuous Evaluation, TE- Term End Evaluation, PE- Practical Evaluation,IE- Internship Evaluation.

Grades A+ 90% and Above Outstanding A 80- 89% Excellent.

B+ 70 - 79% Very Good B 60- 69% GoodC+ 50 - 59% Above Average C 40- 49% Average

D+ 30 - 39% Marginal D 20- 29% Need improvement

E Below 20% Need improvement

SECRETARYMarks Entered byMarks checked bySupdt/ T. O

Government of KeralaBoard of Vocational Higher Secondary Examinations

Reg: No.Thiruvananthapuram

Dated :

Sri./Smt. is awardedScores/grade as detailed below in the First Year Vocational Higher Secondary Examinationheld in

Name of School : Admission No :

Name of Vocational Course :

Evaluation Sheet

64


CURRICULUM OBJECTIVES

I RADIO COMMUNICATION

1.1 To create awareness about basic principle of modulation and demodulationthrough general discussion followed by the presentation of the report.

1.2 To develop an idea of various reasons that makes modulation necessary inradio communication through class room transaction.

1.3 To create a basic idea of different types of modulation (AM and FM ) throughpreparation of chart.

1.4 To create a basic idea of the working of a simple AM modulator circuit throughdemonstration and practical work on laboratory

1.5 To create a basic idea about the working of a simple AM detector (Diodedetector) circuit through demonstration and practical work on laboratory.

1.6 To develop an idea about the working of an AM radio transmitter and familiarizewith its different sections through field visit and preparation of chart.

1.7 To develop an idea about the working of FM radio transmitter and familiarizewith its different section by visiting nearby FM radio station and prepare areport.

1.8 To refresh the basic concept of radio reception through group discussion andpresent the report.

1.9 To introduce basic working principle of super heterodyne AM radio receiverthrough seminar and practical work.

1.10 To discuss the various fault and their remedies of AM radio receivers throughpanel discussion, practical work, typical case studies and prepare notes.

1.11 To develop the idea of FM radio receiver through seminar and demonstrationand submit the report.

1.12 To discuss the various faults and their remedies of FM radio receiver throughpanel discussion, typical case studies and prepare notes.

II AUDIO EQUIPMENTS

2.1 To brush up the knowledge about the working of tape recorder throughdiscussion followed by the presentation of report.

2.2 To develop an idea about the working of record / play back head and erasehead through discussion and present the report.

• MRRTV

65

2.3 To enable the students to identify different parts of tape transport mechanism,its working and its trouble shooting through observation and practical work.

2.4 To introduce the basic concept of monophonic and stereophonic sound systemthrough class room presentation of block diagram and demonstration. Troubleshooting by practical work and presentation of report.

2.5 To familiarize the different controls and connections of PA system throughobservation. Trouble shooting by practical work and presentation of report.

2.6 To introduce the working of CD player through demonstration by practicalwork and present the report.

2.7 To intriduce the working of MP3 player, Dolby system and Dts through surveyand present the report.

III TELEVISION TRANSMISSION

3.1 To introduce the concept of aspect ratio, scanning and interlaced scanningthrough demonstration and class room transaction.

3.2 To develop an idea about vidicon camera tube and its working throughdemonstration of chart, field visit and presentation of report.

3.3 To develop an idea about composite video signal through demonstration andprepare chart and presentation of report.

3.4 To enable the students to get an idea about negative and positive modulationthrough demonstration of diagram followed by the presentation of the report.

3.5 To introduce the concept of vestigial sideband transmission throughdemonstration and class room transaction and presentation of report.

3.6 To introduce the concept of channel band width through demonstration followedby the presentation of the report

3.7 To introduce ghost interference through observation, discussion and presentationof report.

3.8 To introduce the standards of TV transmission through discussion and chartpresentation.

3.9 To introduce the basic concept of TV transmitter, with block diagram throughdiscussion, field visit and presentation of report.

IV MONOCHROME TELEVISION RECEIVER

4.1 To develop an idea about the concepts of TV reception from their previousknowledge of radio reception through brain storming and preparation of thereport.

4.2 To create awareness about the different blocks of monochrome televisionreceiver through classroom transaction, audio visual aids and preparation ofchart

66


4.3 To develop an idea about RF section through assignment, practical experimentand presentation of chart.

4.4 To acquire knowledge about the IF section through demonstration, classroomtransaction and presentation of chart.

4.5 To create an ides about the working of video detector through demonstrationin the lab and preparation of chart

4.6 To develop an idea about the sync section , Synchronous Seperator , Integrator,differentiator, vertical section, horizontal section and yoke through paneldiscussion and preparation of report

4.7 To create awareness about the basic concept of AGC, keyed AGC, delayedAGC and AFC through classroom transaction and preparation of chart.

4.8 To develop an idea about intercarrier sound system and separation of soundthrough classroom transaction and preparation of report.

4.9 To brush up the idea about the sound section through panel discussion, practicalexperiment and preparation of report.

4.10 To get a clear idea about the low voltage power supply through assignment,circuit tracing and voltage measurement.

4.11 To acquire knowledge about the working of EHT (LOT) through demonstrationof different circuits and preparation of chart.

4.12 To familiarize the user controls and technician controls of monochrome TVreceiver through practical experiments.

4.13 To acquire knowledge about monochrome picture tube through observation ,demonstration, preparation of chart and voltage measurements.

4.14 To familiarize the students with common faults of various section of the B&WTV receiver through different practical experiments.

4.15 To get a clear idea about the concept of receiving antennas and the working ofyagi-uda antenna through observation, classroom transaction and practical work.

4.16 To give an idea of twine wire lead and co-axial cable transmission lines throughobservation, general discussion and preparation of notes.

V COLOUR TV RECEIVER

5.1 To get a clear idea about the concept of compatibity and colour fundamentalsthrough brain storming.

5.2 To develop an idea about colour mixing theory through chart demonstration.

5.3 To acquire knowledge about the terms luminance, hue, saturation andchrominance signal through classroom transaction.

5.4 To obtain the basic idea about the extraction of colour difference signals throughdemonstration of block diagram.

• MRRTV

67

5.5 To obtain a clear idea about the colour burst signal and composite colour videosignal through demonstration of chart.

5.6 To introduce the three different colour TV systems-NTSC, PAL and SECAMthrough classroom transaction.

5.7 To introduce an idea about the PAL receiver through demonstation of block diagram.

5.8 To obtain knowledge about the working of PAL receiver through panel discussion.

5.9 To familiarize the students with the user and technician colour controls ofPAL receiver through practical experiments.

5.10 To get a clear idea about the PIL picture tube through demonstration of chart.

5.11 To obtain a basic idea about convergence purity and pincushion correctionthrough class room transaction.

5.12 To get an idea about degaussing and the function of automatic degaussing coilthrough classroom transaction

5.13 To familiarize the students with common faults of various sections of the colourTV receiver and their trouble shooting procedure through different case studies.

5.14 To understand the basic principles of remote control used in television throughassignment.

VI VIDEO EQUIPMENTS

6.1 To acquire knowledge about the basic principle of video cassette player VCP /VCR through classroom transaction, demonstration and preparation of report.

6.2 To develop the idea of different blocks of VCD player through classroomtransaction and preparation of chart

6.3 To familiarize the different controls of VCD player through practicalexperiments and demonstrations

6.4 To familiarize the common faults in VCD player and the methods of their troubleshooting through case studies

6.5 To acquire knowledge about DVD player through group discussion andpreparation of chart

6.6 To familiarize the working of DVD player through general discussion andpractical experiments.

6.7 To familiarize the working of different controls through practical experiments.

6.8 To familiarize the common faults in DVD player and the methods of their troubleshooting through case studies.

6.9 To familiarize the basic concept of digitals camera (still & movie) throughobservation, survey and preparation of report.

6.9 To familiarize the basic concept of TV tunner card through class roomtransaction and practical work.

68


6.10 To familiarise the basic concept of TV tuner card, throguh class room transactionand practical work.

VII SATELLITE COMMUNICATION

7.1 To introduce the basic idea of satellite communication system , through generaldiscussion.

7.2 To familiarize the students with the transponders, digital transmission (basicconcept) Dish Antenna, through field visit and preparation of report.

7.3 To develop an idea about the satellite TV receiver (DTH) through demonstrationof block diagram, practical experiments and field visit

7.4 To familiarize the digital receiver accessories like splitter, connector, repeateretc. through collection and chart preparation.

7.5 To familiarize the students with common faults and trouble shooting connectedwith digital receiver and accessories through typical case studies.

7.6 To obtain a clear idea about basic concept, working and application of CATVand CCTV through survey and preparation of project report

7.7 To get a basic idea about EDUSAT through field visit and preparation of report

VIII ADVANCES IN TELEVISION TECHNOLOGY

8.1 To develop basic idea about the modern television technologies, projectionTelevision, HDTV, OLED TV, Hollographic TV, Mobile TV, Plasma TVetc. through survey, field visit and preparation of report

8.2 To develop basic idea about the modern display technologies - LCD,TFT&DLP

696969

• Maintenance and Repairs of Radio and Television

Part II

Unit Wise Analysis

7070


1.1 IntroductionSince the fundamentals and basic techniques do not change with time, before going into

the depth of the subject, students have to get familiar with the fundamentals. Radio transmissionis an important milestone in the field of communication. This chapter is aimed to give the basicidea about this fact. The objective of this chapter is to make the students aware about modulation(AM and FM), demodulation, different types, block diagram of AM and FM transmitter andblock diagram of radio receiver (AM and FM)

One of the prominent job oriented fields is the servicing and repairing of various electronicdevices. So to enable the students acquainted with the initial steps of servicing and repairing,some typical faults and remedies of AM and FM radio receivers are also discussed here.

1.2 SyllabusModulation and Demodulation: Modulation, Need for modulation types of modulation-

AM and FM modulating circuits. Demodulators (simple circuits only).


Radio Receivers : AM Radio receiver- introduction, super heterodyne receiver - blockdiagram, controls, Typical faults and remedies. FM.


1.3 Curriculum Objectives1.3.1 To create awareness about basic principle of modulation and demodulation through general

discussion followed by the presentation of the report.

1.3.2 To develop an idea about various reasons that make modulation necessary in radiocommunication through classroom transaction

1.3.3 To create a basic idea about different types of modulation (AM and FM) throughpreparation of chart

1.3.4 To create a basic idea about the working of a simple AM modulator circuit throughdemonstration and practical work in the laboratory

1.3.5 To create a basic idea about the working of a simple AM Detector circuit (Diode Detector)through demonstration and practical work in the laboratory

RADIO COMMUNICATION1

717171


1.3.6 To develop an idea about the working of an AM radio transmitter and familiarize with itsdifferent sections through field visit and preparation of chart

1.3.7 To develop an idea about the working of FM radio transmitter and familiarize with itsdifferent sections by visiting near by FM radio station and prepare a report

1.3.8 To refresh the basic concept of radio reception through group discussion and present thereport

1.3.9 To introduce basic working principle of super heterodyne AM radio receiver throughseminar and practical work

1.3.10 To discuss the various faults and their remedies of AM radio receivers through paneldiscussion, practical work, typical case studies and prepare notes

1.3.11 To develop the idea of FM radio receiver through seminar and demonstration andsubmit the report

1.3.12To discuss the various faults and their remedies of FM radio receiver through paneldiscussion, typical case studies and prepare notes.

1.4 Points to be highlighted• Modulation

• Amplitude modulation

• Frequency modulation

• AM modulator

• AM detector

• AM and FM Transmitter

• AM radio receiver

• FM radio receiver

1.5 Learning Activities1.5.1 The teacher can conduct a general discussion on the basic principles of modulation and

demodulation by brushing up their previous knowledge. The students are advised topresent the reports individually.

Discussion Points

1 Modulation

2 Types

3 Need for modulation

1.5.2 The teacher can demonstrate the working of an AM modulator and AM demodulatorthrough chart and explain its working through practical work in the laboratory

1.5.3 The students are asked the prepare colourful charts describing the basics of AM and FMwaves. Comparison by observation of the charts and by listening respective stations arealso directed.

7272


1.5.4 Conducting a field visit to the nearby AM and FM station. The students are directed toidentify the different section of AM an FM radio transmitters. They can also collect thedata's like modulator, oscillator and transmitting antennas. They are also asked to displaythe block diagrams of AM and FM transmitter.

1.5.5 The teacher can conduct a general discussion on the basic concept of radio reception andsuper heterodyne AM radio receiver by brushing up their previous knowledge. Thestudents are directed to present the reports individually.

Discussion points

1. Super heterodyne principle

2. Working of AM radio receiver

Display the block diagram of super heterodyne radio receiver

Construction of AM radio receiver and its fault analysis and trouble shooting by signalinjection and voltage measurement techniques in the practical class

1.5.6 Conducting a seminar on FM radio receiver. The students are directed to present thereport. Study of fault analysis and trouble shooting of FM receiver is recommended

1.6 Practical laboratory workActivity 1.5.2

Activity 1.5.5

1.7 Items for continuous EvaluationSeminar on FM receiver

1.8 Items for T.E1 You are given with an AM radio receiver. Can you identify the different sections of the

receiver? Explain the different section with a neat block diagram

2 From a radio you are able to hear a noise free programme. Can you identify the receiver.Explain its working with suitable block diagram.

1.9 Out put / Out comeDiscussion note, seminar report, practical work recordings, chart, field visit report

1.10 Reference1 Principles of Electronics-V.K.Mehta

2 Electronic Communication systems-Kennedy

3 Basic Radio and Television -S.D.Sharma

4 Electronic Communication-Sanjeeva Gupta

5. www.radioelectronics.com

6 www.radiodesign.com

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757575


1.1 Introduction

External to the ear, sound is a longitudinal wave motion consisting of a train ofcompressions and rare factions travelling in a medium. When sound waves strike the ear-drum, these are converted into electrical signals. The auditory nerves carry these signals to thebrain which interprets them into what we call sound

This Chapter deals with equipments connected with sound like audio tape-recorder (Monoand Stereo) A Detailed version is given in this chapter with block diagrams and typical faultswith remedies

Since the intensity of sound decreases with distance, the need of amplifying the signalarises so that people at a distance from the stage may receive good intensity of sound when alarge gathering is to be addressed. A system which fulfils this function is called public Addresssystem or P.A system. This chapter also aims to give clear idea to students about P.A systemwith its block diagram and trouble shooting procedure.

An outlook is also given to the basic ideas of MP3 system, Dolby system and DTS. Thischapter also gives a detailed overview of the working and trouble shooting of A.C.D player

2.2 Syllabus

Audio tape recorder (Mono and Stereo) - Introduction, block diagram, controls, typicalfaults and remedies - Public Address System- Introduction, block diagram, trouble shooting -CD Player- Introduction, block diagram, MP3 system, Dolby system, DTS (basic treatmentonly.

2.3 Curriculum objectives:2.3.1 To brush up the knowledge about the working of tape recorder through discussions

followed by the presentation of report

2.3.2 To develop an idea about the working of record / play back head and erase head throughdiscussion and present the report

2.3.3 To enable the students to identify different parts of tape transport mechanism, its workingand its trouble shooting through observation and practical work.

AUDIO EQUIPMENTS2

7676


2.3.4 To introduce the basic concept of monophonic and stereophonic sound system throughclassroom presentation of block diagram and demonstration. Trouble shooting by practicalwork and presentation of report

2.3.5 To familiarize the different controls and connections of PA system through observationand trouble shooting by practical work and presentation of report

2.3.6 To introduce the working of CD player through demonstration by practical work andpresent the report

2.3.7 To introduce the working of MP3 player, Dolby system and DTS through survey andpresent the report

2.4 Points to be Highlighted:

• Tape recorder

• Monophony and stereophony

• Public Address system

• CD Player

• Dolby system

• DTS

2.5 Learning Activities:2.5.1 The teacher can conduct a general discussion regarding the working of tape recorder by

brushing up the previous knowledge of the students. The students are then asked topresent a detailed report about the working

2.5.2 Demonstration of internal structure of a tape recorder and explanation about the workingof different parts including the tape transport mechanism can be done in the laboratory.The teacher can also explain different faults and their trouble shooting procedures in thepractical class

2.5.3 The teacher can conduct a discussion on monophonic and stereophonic sound systemand introduce the basic concept through classroom transaction. They can be practicallyobserved and compared . The block diagrams can be developed by discussion. One ofthe students may present a report.

2.5.4 Demonstrating a public system and familiarizing the different controls and connectionsthrough practical work. The students are asked to present as report. The trouble shootingcan be done with the practical work

2.5.5 A CD player is demonstrated in the classroom and the students are asked to prepare areport on the working with block diagram. The trouble shooting in a CD player can bedone with the practical work.

777777


2.5.6 The students are asked to conduct a survey on MP3 player, Dolby system and Dts. Thestudents can present the reports on the classroom and the teacher can consolidate theworking

2.6 Practical Laboratory work

Activity 2.5.2

Activity 2.5.4

Activity 2.5.5

2.7 C.E Items

Survey on MP3 player, Dolby system and Dts.

2.8 T.E Items1 What will be the difference in effect when we hear a programme in monophony and

stereophony? Why?

2 You are directed to install a PA system in year school for a function. Draw the connectiondiagram you are going to instal.

2.9 Output / Outcome / Product:

Discussion notes, Survey report, Practical work recordings, charts.

2.10 Reference1 Audio and video Engineering- R.G.Gupta

2. www.howstuffworks.com

3. www.cd-info.com

ADDENDUM

Dts - Digital Theatre System

- Multichannel Surround Sound used for both commercial/theatrical andconsumer grade applications.

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797979


TELEVISION TRANSMISSION3

3.1 Introduction

Television stands for "seeing at a distance" It became possible when variations in brightnessand colour could be converted into electrical variations at the transmitter and the electricalsignals reconverted into brightness and colour at the receiver

This chapter introduces the basic principles used for converting the variations in lightintensity into electrical signal and how it can be transmitted to long distances with the help ofa radio frequency carrier. At the receiver end, the video signals can be recovered from themodulated wave by adopting the techniques of super heterodyne detection and amplification.TV transmission and reception is not as easy as audio transmission and reception. The chapterbegins with a description of what TV must produce and the standards that must be definedinorder to produce this. A brief idea is then given as to how the picture signal and the soundinformation is transmitted on the same channel. Vidicon camera tube is also mentioned here.The unit also deals with the elements of monochrome transmission, scanning, synchronizationand transmitting antennas.

3.2 Syllabus

Introduction, aspect ratio, scanning, interlaced scanning, TV camera tube (vidicon),composite video signa, negative modulation, VSB transmission, intereference, TV transmissionstandards, television transmitter - Block diagram.

3.3 Curriculum Objectives:3.3.1 To introduce the concept of aspect ratio, scanning and interlaced scanning through

demonstration and classroom transaction

3.3.2 To develop an idea about vidicon camera tube and its working through demonstration ofchart, field visit and presentation of report

3.3.3 To develop an idea about composite video signal through demonstration, prepare chartand presentation of report

3.3.4 To enable the students to get an idea about negative and positive modulation throughdemonstration of diagram followed by the presentation of the report

3.3.5 To introduce the concept of Vestigial Side Band transmission through demonstration andclassroom transaction and preparation of report

8080


3.3.6 To introduce the concept of channel band width through demonstration followed by thepresentation of the report

3.3.7 To introduce Ghost interference through observation, discussion and presentation of report

3.3.8 To introduce the standards of TV transmission through discussion and chart presentation

3.3.9 To introduce the basic concept of TV transmitter with block diagram through discussion,field visit and presentation of report


• Interlaced Scanning

• Composite video signal

• Vidicon camera tube

• Negative Modulation

• VSB transmission and channel band width

• TV transmission standards

• TV transmitter (Block diagram)

3.5 Learning Activities:3.5.1 The teacher can introduce the concept of aspect ratio, scanning and interlaced scanning

through chart preparation and the students are directed to read the chart and through thatactivity the idea of scanning and interlaced scanning can be better conveyed

3.5.2 The teacher can demonstrate the idea about vidicon camera tube and enable the students torecollect all their doubts about camera and ask them to prepare a questionnaire and clear allthose doubts through a field visit. Students are also directed the present the report

The teacher can explain the concept of synchronization through classroom transactionwith example

3.5.3 The teacher can demonstrate the composite video signal on CRO and explain. Studentsare directed to present a report

3.5.4 The teacher can demonstrate the idea about negative and positive modulation, vestigialside band transmission and channel band width through chart preparation and classroomtransaction. Students are directed to find the picture carrier and sound carrier of differentchannels. They are asked to prepare individual report

3.5.5 The teacher can convey the idea of ghost inference through discussions and the inferencecan be observed in the Television receiver by adjusting the receiving antenna and studentscan observe it in the lab and they are also directed to present a report

818181


3.5.6 The teacher can demonstrate about the standards of TV transmission through a chartpresentation

3.5.7 The teacher can conduct a general discussion about the basic concept of TV transmission,propagation of wave, antennas and transmission lines and help the students to prepare aquestionnaire covering all the above aspects and the answers can be collected through afield visit. Students are also directed to present an individual report

3.6 C.E Items

Study of vidicon camera tube through a field visit to a near by TV transmission station.

3.7 TE Items1 Name the instrument which can be used to convert picture signal to electrical signal.

Explain with a diagram, such type of an instrument which is commonly used

2 With a block diagram explain the working of a TV transmitter

3.8 Output / Outcome / Product

Report presentation, Report of the field visit conducted, chart presentation

3.9 Reference1 Monochrome and color Television - R.R.Gulati

2 Basic Radio and Television - S.D.Sharma

3 Audio and video Engineering - R.G.Guptha

8282


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8484


MONOCHROME TV RECEIVER4

4.1 Introduction

A black and white receiver has six main sections - Tuner, IF, Video, Audio, deflectionand power supply. The tuner selects the desired channel signal from those picked up by theantenna and converts it into the Intermediate frequencies. The IF section provides largeamplification to the weak IF signal and the video detector produce composite video and intercarrier FM sound signals. The video signal is amplified and fed to the picture tube. Similarlythe inter carrier sound IF signal is amplified, limited and detected to obtain audio signal. Theweak audio signal is given sufficient amplification to obtain the desired audio signal. Thischapter is designed to describe functions of various sections of a monochrome receiver withoutgoing into circuit details.

4.2 Syllabus

Introduction, block diagram-explanation, RF section, IF section, Video detector, Syncsection, Horizontal and vertical section, AGC & AFC, Sound section, Power supply andEHT. User antenna and transmission lines trouble shooting of different stages.

4.3 Curriculum Objectives4.3.1 To develop an idea about the concepts of TV reception from their previous knowledge

of radio reception through brain storming and preparation of the report.

4.3.2 To create awareness about the different blocks of monochrome television receiverthrough classroom transaction , audio visual aids and preparation of chart

4.3.3 To develop an idea about RF section through assignment , practical experiment andpresentation of chart

4.3.4 To acquire knowledge about the IF section through demonstration, classroom transactionand preparation of chart

4.3.5 To create an idea about the working of video detector through demonstration in the laband preparation of chart

4.3.6 To develop an idea about the sync section, synchronous separator, Integratordifferentiator, vertical section, horizontal section and yoke through panel discussionand preparation of report

858585


4.3.7 To create awareness about the basic concept of AGC, keyed AGC and delayed AGCand AFC through class room transaction and preparation of chart.

4.3.8 To develop an idea about inter carrier sound system and separation of sound throughclass room transaction and preparation of report.

4.3.9 To brush up the idea about the sound section through panel discussion, practicalexperiment and preparation of report.

4.3.10 To get a clear idea about the low voltage power supply through assignment, circuittracing and voltage measurement.

4.3.11 To acquire knowledge about the working of EHT (LOT) through demonstration ofdifferent circuits and preparation of chart.

4.3.12 To familiarize the user controls and technician controls of monochrome TV receiverthrough practical experiments.

4.3.13 To acquire knowledge about monochrome picture tube through observation,demonstration, preparation of chart and voltage measurement.

4.3.14 To familiarize the students with common faults of various section of the black andwhite TV receiver and their trouble shooting procedure through different practicalexperiments or through field visit.

4.3.15 To get a clear idea about the concept of receiving antennas and the working of Yagi-uda antenna through observation, classroom transaction and practical work in the lab.

4.3.16 To give an idea of twin wire lead and co-axial cable transmission lines throughobservation, general discussion and preparation of notes.


• Block diagram of monochrome TV Receiver

• AGC, AFC, EHT

• Yagi-uda antenna

• Monochrome Picture tube

• Typical faults and remedies

4.5 Learning Activities4.5.1 The teacher can conduct a brain storming section to introduce the basic concepts of radio

reception and can there by brush up their previous knowledge. From that the principlesof TV reception can be introduced. The students can present a report on TV reception

4.5.2 The teacher can introduce the basic block diagram of monochrome TV receiver by usingoverhead projector. The students must be asked to prepare colorful charts individually

4.5.3 The students are asked top prepare an assignment on VHF and UHF tuners. The teachercan demonstrate the tuner sections of receiver and can differentiate between them.

8686


4.5.4 The teacher can demonstrate the diagram and circuit board of IF amplifier, wave trapsand video detector sections to the students and should explain briefly their working.

4.5.5 The teacher can conduct a panel discussion on raster section (Sync Separator, integrator,differentiator, vertical section, horizontal section and yoke) The reports can be presentedand the teacher can consolidate the ideas

4.5.6 The teacher can demonstrate the block diagrams of AGC, keyed AGC and delayed AGCand explain their working. Separate charts can be prepared by the students

4.5.7 The teacher can introduce the inter carrier sound system and separation of sound to thestudents through classroom transaction and prepare the notes individually. A paneldiscussion is conducted on sound section and present the report. A practical experimentis conducted on sound section

4.5.8 The students are asked to prepare an assignment on the low voltage power supply (SMPS)A practical work is conducted to trace the circuit board and the voltages are measured

4.5.9 Conduct a practical session to familiarize the user controls and technician controls ofmonochrome TV receiver

4.5.10 The teacher can demonstrate a monochrome picture tube and the students are directedto observe the various aspects of the picture tube. The teacher can explain the workingand voltages at different pins are also measured. Students are asked to prepare individualreport.

4.5.11 The teacher can conduct a practical experiment on fault finding and trouble shooting ofmonochrome TV receiver in laboratory and can conduct a field visit to a near by TVservice station

4.5.12 The teacher can demonstrate Yagi antenna and different cables to the students and canmake the connections practically.

4.5.13 The teacher can demonstrate the circuit board of EHT and explain its working. Thestudents are asked to prepare the reports.

4.6 Practical Laboratory work:

Activity-4.5.8

Activity-4.5.9

Activity-4.5.11

Activity-4.5.12

Activity-4.5.13

4.7 CE Items

Chart preparation, Assignment on VHF & UHF tuner,

Assignment on SMPS

878787


4.8 TE Items1 Your friend Anu is trying to identify the different parts of a monochrome TV receiver.

He identified the following parts

(1) Picture tube, (2) Loud speaker, (3) Antenna, (4) LOT (5) Video amplifier (6) bSync separator (7) RF tuner. Can you help him to identify the rest of the parts and alsoshow them in the proper order by drawing the block diagram?

2 Where and how the sound signals are separated in a TV receiver?

4.9 Output / Outcome / Product

Discussion notes, charts, assignment, practical work report.

4.10 Reference

1. Audio and Video Engineering -R.G.Gupta

2. Monochrome and color Television - R.R.Gulati

3. Modern Television Practice - R.R.Gulati


ADDENDUM

Digital Camera

- No film or processing is required.

- Filmless digital cameras are a technological advancement in the professional photographyworld. Electronic sensors inside the camera transmit the different levels of liht, whichenter through the red, green, and blue fitters on to a CCD (photo sensitive semiconductor)

- The CCD digitally records the image and stores it into a PCM-CIA card - a tiny hard discdrive.

8888


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919191


COLOUR TV RECEIVER5

5.1 Introduction

The quest for more comfort and pleasure is a material instinct driving the mankind. Oncethe dream of visualizing live scenes was satisfied, the next attempt was to make it more livelyand realistic. Colour television with its material appearance was a real milestone in this effortwhich is still proceeding with a greater momentum.

In colour television, an additional signal carrying the colour information - the chrominanacesignal is to be accomodated along with the luminance and sound signals. Ofcourse, thetransmitting and receiving equipments are to be modified to meet his additional requirement. Ina colour TV reciever it is the chroma section which handles the colour signal and converts itinto the realistic colours on the screen. In this effort it requires the help of certain auxilliarycircuits and a few minor (not always) modifications of the existing ones.

This chapter gives an overall idea aobut the major functionaries of a CTV receiver, thePAL-D decoder being taken as the role model (Americans please excuse). Intrusive treatmentof all the circuit details are not intended, but mentioned as and when warrenteed.

Finally a logical approach to the trouble shooting is presented with a few tips that may serveas a ready reckoner. But remember, trouble shooting is a skillful art that can be nurtured onlythrough hands on work and experience and can never be injected in a single doss to one’s mind.

5.2 Syllabus

Introduction, compatibility, colour fundamentals, colour mixing, luminance andchrominance signal, colour difference signals, colour synchronization and burst, colour compositevideo signal, colour TV systems - NTSC, PAL, SECAM (Basic Concept only). PAL colourreceiver, Block diagram description. User and technician controls, PIL colour picture tube,convergence and purity, basic idea, pincushion distortion, Automatic degaussing, trouble shootingin colour TV receivers. Remote control-Basic principle.

5.3 Curriculum Objectives5.3.1 To get a clear idea about the concept of compatibility and colour fundamentals through

brain storming.

5.3.2 To develop an idea about colour mixing theory through chart demonstration

9292


5.3.3 To acquire knowledge about the terms luminance, hue, saturation and chrominancesignal through classroom transaction

5.3.4 To obtain the basic idea about the extraction of colour difference signals throughdemonstration of block diagram.

5.3.5 To obtain a clear idea about the colour burst signal and composite colour video signalthrough demonstration of chart.

5.3.6 To introduce the three different colour TV systems - NTSC, PAL and SECAM throughclassroom transaction.

5.3.7 To introduce the idea about PAL receiver through demonstration of block diagram.

5.3.8 To obtain knowledge about the working of PAL receiver through panel discussion

5.3.9 To familiarize the students with the user and technician controls of PAL receiver throughpractical experiments.

5.3.10 To get a clear idea about the PIL picture tube through demonstration of chart.

5.3.11 To obtain a basic idea about convergence, purity and pincushion correction throughclassroom transaction.

5.3.12 To get an idea about degaussing and the function of automatic degaussing coil throughclassroom transaction

5.3.13 To familiarize the students with common faults of various sections of the colour TVreceiver and their trouble shooting procedure through different case studies.

5.3.14 To understand the basic principles of remote control used in television through assignment.

5.4 Points to be Highlighted

• Compatibility, Hue, Luminance and saturation

• Colour composite video signal

• Colour burst signal

• PIL picture tube

• Degaussing, Purity and convergence

• Remote control

• Typical faults and remedies in colour TV

5.5 Learning Activities:5.5.1 The teacher can conduct a brain storming section on compatibility, fundamentals of

colour, persistence of vision etc. which help them to refresh the knowledge

5.5.2 With the help of chart, introduce the concept of both additive and subtractive colourmixing.

939393


5.5.3 Conduct a discussion about the terms luminance, hue, saturation, Y-signal andchrominance signal. Also with the help of block diagram, explain the extraction ofcolour difference signal and the formation of Y signal.

5.5.4 With the help of chart demonstrate the idea of colour burst and composite colour videosignal. The colour burst and composite colour video signal can be observed during thefield visit.

5.5.5 The teacher can convey the idea of the three difference colour TV systems (NTSC,PAL and SECAM) by preparing a chart and through classroom transaction.

5.5.6 The teacher can demonstrate the idea and working of the PAL receiver throughpreparation of block diagram. An OHP can be used. Students are asked to preparecharts individually.

5.5.7 Conduct a practical session to familiarize with the user controls and technician controlsof the PAL receiver. Can conduct a visit to a nearby TV service station

5.5.8 The teacher can demonstrate the working of PIL picture tube through chart preparation.

5.5.9 The teacher can convey the basic idea about convergence, purity, pincushion correction,degaussing and automatic degaussing through classroom transaction. Students are askedto prepare chart.

5.5.10 The teacher can conduct practical experiments on fault finding and trouble shooting ofcolour TV receiver in the laboratory and can conduct a field visit to a near by colourTV service station

5.5.11 Students are asked to submit an assignment on remote control used in TV receiver andare directed to practice its working in the laboratory.

5.6 Practical laboratory work

Activity 5.5.7

Activity 5.5.10

5.7 CE Items

Assignment on remote control

5.8 TE Items1. Suppose you are TV technician and let a customer approach you with a faulty TV. From

your observation you found a monochrome display in that colour TV

(A) Can you identify the faulty stage?

(B) What are the probable faults you expect in that section?

(C) Write the trouble shooting procedure for the particular fault?

2. Describe the automatic method of removing colour patches in the TV screen.

9494


2.9 Reference

1. Monochrome and colour Television - R.R.Gulati


3. www.epanorama.net


959595


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art

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o in

trod

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thre

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ent

colo

ur t

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AL

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stem

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SC,

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e be

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cebo

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rnet

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aJo

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ls

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conc

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ms.

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ss t

rans

ac-

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IT A

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OL

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Cha

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note

s

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rt

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ort

9696


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ricu

lum

Obj

ectiv

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once

pt/

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cept

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oces

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ctiv

ities

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ning

Eval

uatio

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rea

idea

ssk

ills

mat

eria

lsO

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me

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o in

trod

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idea

abo

utth

e PA

L r

ecei

ver.

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colo

urre

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er

Blo

ck d

ia-

gram

of

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ceiv

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onst

ratio

nB

lock

di

agra

man

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ing

8.T

o ob

tain

kn

owle

dge

abou

t th

e w

orki

ng o

f PA

Lre

ceiv

er.

9.To

fam

iliar

ise

the

stud

ents

wit

h th

e us

er

and

tech

nici

an c

ontro

ls o

f PA

Lre

ceiv

er.

PA

Lco

lour

re-

ceiv

er.

Wor

king

of

PA

L

re-

ceiv

er.

Pane

ldi

scus

sion

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lyse

the

wor

k-in

g of

eac

h bl

ock.

Con

trols

of

PA

L

re-

ceiv

er

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r an

dte

chni

cian

cont

rols

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tical

expe

rim

ent

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lity

to

unde

r-st

and

and

to o

per-

ate

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cont

rols

.

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eren

cebo

oks,

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cuss

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note

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fe

re

nc

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lock

diag

ram

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is-

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eren

cebo

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tical

reco

rd

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form

ance

in

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disc

ussi

on.

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lity

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naly

seth

e fu

ncti

ons

ofea

ch b

lock

.

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lity

to d

o pr

ac-

tical

in

the

labo

ra-

tory

.

10.

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get

a cl

ear

idea

abo

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e P

SL

pi

ctur

e tu

beth

roug

h de

mon

stra

tion

ofch

art.

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our

pict

ure

tube

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king

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tub

e.U

nder

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d ho

wco

lour

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ails

are

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uced

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scre

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rtO

HP

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para

tion

of

char

tD

emon

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cuss

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n ba

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, pu

rity

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pine

ushi

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erge

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our

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ts

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lity

to

corr

ect

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igna

lson

scr

een.

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ss r

oom

tran

sact

ion.

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get

an

idea

ab

out

dega

auss

ing

and

the

func

tion

of

au

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atic

dega

usin

g co

il.

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eed

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ussi

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ing.

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ss

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erst

and-

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ct

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es

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cuss

ion

note

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tical

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rd

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rt

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erst

and-

ing

of fa

ct

979797


Cur

ricu

lum

Obj

ectiv

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once

pt/

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cept

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oces

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ctiv

ities

Lear

ning

Eval

uatio

nO

utpu

t/A

rea

idea

ssk

ills

mat

eria

lsO

utco

me

13.

To f

amili

aris

e th

e st

uden

tsw

ith

com

mon

fau

lts

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rious

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tions

of

colo

urT

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ecei

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and

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ble

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ting

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e.

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mon

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ts a

ndtr

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ng

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nd-

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ng

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e st

udie

sId

enti

fica

tion

of

the

faul

t an

d ab

ility

to r

ectif

y it.

14.

To

unde

rsta

nd t

he b

asic

prin

cipl

es o

f re

mot

e co

ntro

lus

ed i

n Te

levi

sion

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mo

teco

ntro

lPr

inci

ple

ofre

mot

e -

cont

rol

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ignm

ent,

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ion

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king

pri

ncip

leof

rem

ote

cont

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uble

shoo

ting

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t

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eren

cebo

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r-na

ls

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ifya

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and

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rect

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lect

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ata.

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ot

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ignm

ent

9898


VIDEO EQUIPMENTS6

6.1 Introduction

The field of Electronics has grown to such an extent that VCDs and DVDs have stolenthe place of earlier VCPs / VCRs in video recording and reproduction. Now a days Digitalsignal processing over ruled the analog type due to many advantages.

This chapter covers the basic details of tape recording and both the theoretical and practicalaspects of modern digital video equipments like VCD, DVD, Digital camera and the installingof TV tuner card in computer. It may not be so easy to cover each and every type of VCD/DVD/Digital Camera/TV tuner card, but a noble attempt is made to cover different aspects ofthese instruments like familiarization, typical faults study and their trouble shooting procedures.

6.2 Syllabus

Video cassette player / recorder - Introduction, Basic principle, VCD player - Blockdiagram, Working, controls, trouble shooting. DVD player (Basic concept only), Digitalcamera - Introduction and basic concept, TV Tuner card - Introduction

6.3 Curriculum Objectives6.3.1 To acquire knowledge about the basic principle of video cassette player VCP /VCR

through class room transaction, demonstration and preparation of report

6.3.2 To develop the idea of different blocks of VCD player through classroom transactionand preparation of Chart

6.3.3 To familiarize the different controls of VCD player through practical experiments anddemonstration

6.3.4 To familiarize the common faults in VCD player and the methods of their trouble shootingthrough case studies

6.3.5 To acquire knowledge about different blocks of DVD player through group discussionand preparation of chart

6.3.6 To familiarize the working of DVD player through general discussion and practicalexperiments

6.3.7 To familiarize the working of different controls through practical experiments

999999


6.3.8 To familiarize the common faults in DVD player and the methods of their trouble shootingthrough case studies

6.3.9 To familiarize the basic concept of digital camera (Still and movie) through observationsurvey and preparation of report.

6.3.10.To familiarise the basic concept of TV tuner card, throguh class room transaction andpractical work.


• VCP / VCR

• VCD Player

• DVD Player

• Introduction to- Digital camera, TV tuner card.

6.5 Learning Activities:6.5.1 Demonstrate to the students the internal structure of a VCP/VCR and explain the functions

of different devices / components therein. Students are then asked to collect as much dataas they could and prepare a detailed report

6.5.2 Students are asked to refresh their knowledge about CD player. With the help of blockdiagram, explain to them the working of CD player. Demonstrate the internal structureof VCD player and explain the working of laser eye, different motors etc. Familiarizethem with different circuits of VCD player and the methods of trouble shooting differentfaults. Ask students to make a detailed report with the help of charts individually.

6.5.3 Introduce the concept of DVD player through classroom transaction. Introduce DVDplayer to the class and help students to get familiarized with the working of differentcontrols in it. Also help students in trouble shooting different faults in it through practicalexperiment in the laboratory

6.5.4 Demonstrate a still and movie camera in the classroom and give them the basic conceptand working principle of that. Ask them to prepare a detailed report of the above said byconducting a survey.

6.5.5 Demonstrate the installation of TV tuner card as practical work in the laboratory.


Activity 6.5.2

Activity 6.5.3

Activity 6.5.5

6.7 C.E Items

Data collection on VCR/VCP, VCD & DVD

100100


6.8 T.E Items1 Compare VCD with DVD

2 Explain with block diagram the working of a VCD player

6.9 Output/ Outcome / Product

Report on Data collection, Demonstration report, Practical work report, Survey report

6.10 Reference

1 Audio and video Engineering -R.G. Gupta

2 Monochrome and colour TV - R.R.Gulathi

3. ww.cd-info.com

4. www.play-hookey.com


ADDENDUM

DVD Player- Has much larger data capacity than CD (7 times)

- Upto 133 minutes of high -resolution video

- Provides 5.1 channel Dolby Digital Surround Sound/DTS

- Picture quality better than CDs

- Compatible with audio CDs

- DVD movies have several sound tracks on them.

- It is possible to select the part of the movie we want to view with remote, which eliminatesthe need of fast-forward or fast rewind.

- Multi layer storage

Single - sided/Single layer - 4.38 GB

Single - sided/ double layer - 7.95 GBDouble - sided/ Singlelayer - 8.75 GBDouble - sided/double layer - 15.9 GB

101101101


Cur

ricu

lum

Obj

ectiv

esC

once

pt/

Con

cept

/Pr

oces

sA

ctiv

ities

Lear

ning

Eval

uatio

nO

utpu

t/A

rea

idea

ssk

ills

mat

eria

lsO

utco

me

1.T

o ac

quir

e kn

owle

dge

abou

t the

bas

ic p

rinci

ple

ofvi

deo

cass

ette

pla

yer.

Vid

eoeq

uip-

men

ts

VC

P/V

CR

Cla

ss r

oom

tran

sact

ion,

dem

onst

ratio

n,pr

epar

atio

n of

repo

rt

To

deve

lop

the

wor

king

id

ea

ofV

CP/

VC

R.

2.T

o de

velo

p th

e id

ea o

fdi

ffer

ent

bloc

ks o

f V

CD

play

er.

3.To

fam

iliar

ise

the

diff

eren

tco

ntro

ls o

f V

CD

pla

yer.

Vid

eoeq

uip-

men

ts

VC

D p

laye

rC

lass

ro

omtr

ansa

ctio

nP

repa

rati

on o

fch

art

To

deve

lop

the

wor

king

id

ea

ofV

CD

Pla

yer.

Vid

eoeq

uip-

men

ts

VC

D P

laye

rD

emon

stra

tion,

Prac

tical

expe

rmen

t

To

deve

lop

the

idea

abo

ut V

CD

play

er.

Prac

tica

l sk

ill

abou

t V

CD

pla

yer

Cha

rtSa

mpl

e V

CP/

VC

R

Cha

rt

Sam

ple

VC

Dpl

ayer

VC

D

play

er,

Serv

ice

equi

p-m

ents

inl

cudi

ngC

RO

, m

ultim

e-di

a, C

hart

Kno

wle

dge

abou

tV

CP/

VC

RPr

acti

cal

know

l-ed

ge

abou

t th

ew

orki

ng o

f V

CP/

VC

RK

now

abo

ut w

ork-

ing

of V

CD

Pla

yer

Kno

wle

dge

abou

tth

e w

orki

ng

ofV

CD

pla

yer.

Prac

tica

l sk

ill

abou

t se

rvic

ing

ofV

CD

pla

yer.

4.To

fam

iliar

ise

the

com

mon

faul

ts i

n V

CD

pla

yer

and

thei

r tr

oubl

e sh

ootin

g.

Vid

eoeq

uip-

men

ts

VC

D P

laye

rTo

acq

uire

pra

cti-

cal

know

ledg

eco

veri

ng

faul

tsan

d re

med

ies

ofV

CD

pla

yer.

VC

D

play

er,

serv

ice

equi

p-m

ents

, C

hart

Kno

wle

dge

abou

tfa

ult

find

ing

and

troub

le s

hoot

ing

ofV

CD

pal

yer

Pra

ctic

al e

x-pe

rimen

t, ch

art

of t

ypic

al, c

ase

stud

ies.

5.T

o ac

quir

e kn

owle

dge

abou

t D

VD

pla

yer

Vid

eoeq

uip-

men

ts

DV

D P

laye

rT

o de

velo

p th

ekn

owle

dge

abou

tD

VD

pla

yer.

Cha

rtK

now

ledg

e ab

out

DV

D

play

erba

sics

.

Gro

up

disc

us-

sion

, ch

art

prep

arat

ion

6.To

fam

iliar

ise

the

wor

king

of D

VD

pla

yer.

Vid

eoeq

uip-

men

ts

DV

D P

laye

rTo

dev

elop

a t

hor-

ough

kn

owle

dge

abou

t th

e w

orki

ngof

DV

D p

laye

r.T

o at

tain

pra

ctic

alsk

ill

abou

t D

VD

play

er.

A s

ampl

eD

VD

pla

yer,

Serv

icin

geq

uipm

ents

,C

hart

Idea

abo

ut D

VD

play

er

wor

king

and

serv

icin

g.

Gen

eral

dis

cus-

sion

, P

ract

ical

expe

rim

ent.

Cha

rt an

dre

port

Rep

ort

Rep

ort

Rep

ort

Rep

ort

Cha

rt

UN

IT A

NA

LY

SIS

- 6 V

IDE

O E

QU

IPM

EN

TS

102102


Cur

ricu

lum

Obj

ectiv

esC

once

pt/

Con

cept

/Pr

oces

sA

ctiv

ities

Lear

ning

Eval

uatio

nO

utpu

t/A

rea

idea

ssk

ills

mat

eria

lsO

utco

me

7.To

fam

iliar

ise

the

wor

king

of d

iffe

rent

con

trol

s of

DV

D p

laye

r.

Vid

eoeq

uip-

men

ts

DV

D p

laye

rPr

actic

alex

peri

men

tT

o m

ake

fam

ilia

rw

ith

the

diff

eren

tco

ntro

ls o

f D

VD

play

er.

8.T

o fa

mil

iari

se

the

com

mon

fau

lts

in D

VD

play

er a

nd t

heir

tro

uble

shoo

ting

proc

edur

e.

9.T

o fa

mil

iari

se t

he b

asic

conc

ept

of d

igita

l ca

mer

a(s

till

and

mov

ing)

Vid

eoeq

uip-

men

ts

Serv

icin

g of

DV

D p

laye

rT

ypic

al

case

stud

ies

Prac

tical

exp

eri-

men

t

To

get

know

ledg

eab

out

serv

icin

g of

DV

D p

laye

r.

Vid

eoeq

uip-

men

ts

Dig

ital

cam

era

Obs

erva

tion,

surv

ey,

Prep

arat

ion

ofre

port

.

To

get

idea

abo

utdi

gita

l ca

mer

a.

DV

D p

laye

r,se

rvic

ing

kit

DV

D p

laye

r,se

rvic

ing

kit

A s

ampl

e di

gita

lca

mer

a, c

hart

Kno

wle

dge

abou

tse

rvic

ing

of D

VD

play

er.

Pra

ctic

al

know

l-ed

ge a

bout

ser

vic-

ing

of D

VD

pla

yer

Kno

w h

ow a

bout

basi

cs

of

digi

tal

cam

era.

Rep

ort

Rep

ort

Sur

vey

re-

port

, ch

art

10.

To f

amili

arise

the

bas

icco

ncep

t of T

V tu

ner c

ard,

thro

guh

clas

s ro

omtra

nsac

tion

and

prac

tical

work

.

Vid

eoeq

uip-

men

ts

TV t

uner

card

Prac

tical

wor

kT

o ge

t id

ea a

bout

TV

tun

er c

ard.

P.C

, tu

ner

card

,C

able

Pra

ctic

al e

xper

i-en

ce

on

asse

m-

blin

g an

d se

rvic

ing

Prac

tical

reco

rd,

Rep

ort

103103103


SATELITE TELEVISION7

7.1 Introduction

Considering the limitations of ground and sky wave propagation, the space wavepropagation arises as an alternative. Despite of large attenuation in this mode, it has an advantagethat these waves are not refracted by ionospheric layers. To extend the transmission distance ofradio waves in the VHF and UHF micro wave bands, the technique of communication satellitesare introduced. The technique involved for transmission via satellite is quite complex, but anattempt has been made in this chapter to convey the essentials of satellite TV Cable TV (CATV)was initially introduced for the benefit of communities in rural areas that were beyond the rangeof brodcasting, especially for those living in shadow zones. Modern cable system carry anumber of modern techniques and this has generated great interest and demand from the public.In this chapter, an over view of different aspects of cable TV is covered. CCTV is one of themost popular visual systems which has a wide application area in modern life. An attempt ismade in this chapter to convey the basic idea about CCTV to the students.

This chapter also covers the impact of digital technology on TV transmission and reception

The Direct to Home satellite TV (DTH) system enables viewers to receive many channelsof high quality TV programmes via high powered KU-Band satellites. DTH is similar toDigital satellite system. However since it needs more explanation, a detailed version withblock diagram is given in this chapter.

7.2 Syllabus

Introduction, satellite communication system, transponders, digital transmission-basicprinciple, dish antenna, satellite receiver DTH-block diagram, working, accessories(splitter,connector, repeater) trouble shooting (cable TV & closed circuit TV-basic principle)working, application, EDUSAT Introduction, application.

7.3 Curriculum Objectives7.3.1 Ti introduce the basic idea of satellite communication system, through general discussion

7.3.2 To familiarize the students with the transponders, digital transmission (basic concept)Dish antenna through field visit and preparation of report

7.3.3 To develop an idea about satellite TV receiver (DTH) through demonstration of blockdiagram, practical experiments and field visit

104104


7.3.4 To familiarize the digital receiver, accessories like splitter, connector, repeater, etc. throughcollection and chart preparation

7.3.5 To familiarize the students with common faults and troubleshooting connected with digitalreceiver accessories through typical case studies

7.3.6 To obtain a clear idea about basic concept, working and application of CATV and CCTVthrough survey and preparation of project report

7.3.7 To get a basic idea about EDUSAT through field visit and preparation of reaport.


• Digital transmission

• DTH system

• Satellite communication

• Cable TV

• CCTV

• EDUSAT

7.5 Learning Activities:7.5.1 Ask students to refresh their knowledge about satellite communication and also discuss

about different satellites (communication) of India and different frequency bands throughwhich communication is carried out

7.5.2 Help students to prepare a questionnaire about satellite reception. Conduct a field visit tothe nearby cable operating station from where they could collect ideas regarding Dishantenna, wave guides, digital receiver, transponder, up linking, down linking and alsoabout various accessories like splitter, connector etc. Also help them to make a detailedreport with block diagram if necessary

7.5.3 Ask students to collect as much as faulty and scrap accessories of dish antenna as theycan from nearby service centers or from cable operators. Tell the students to prepare achart showing their functions, where used, what for etc.

7.5.4 Introduce the concept of troubleshooting of different faults connected with digital receiverthrough different case studies and with the help of charts

7.5.5 Ask students to conduct a survey regarding basic concept , working installation andapplication of CATV and CCTV Help them to prepare a detailed report as study project.

7.5.6 Take students to nearby Edusat centers and help them to acquire knowledge regardingthe transmission, reception and advantages. Ask the students to prepare detailed reportwith the help of colourful chart as an assignment.

105105105



Activity 7.5.4

7.7. CE Items

Report on satellite receiver after field visit, Chart preparation of different accessories ofdish antenna after site inspection. Survey report on CATV and CCTV.

7.8 T.E Items1 Suppose in your home you have a cable connection from a private agency. They are

hiking the monthly subscription in each month and you want to stop their connection.Do you know an alternative method to get the same channels directly in your home?Explain that technique with a block diagram

2 Suppose you are attending a wedding reception in an auditorium. At all corners of theauditorium, TV monitors are installed. Each one can watch the ceremoney from everycorner . Name and Explain the working of that system, with block diagram

7.9 Reference1. Monochrome and colour Television - R.R.Gulathi

2. Modern Television Practice - R.R.Gulathi

ADDENDUM

DTH - Direct to Home Television

- Reception of satellite programme with a personal dish.

- No need of cable operator and puts the broadcaster directly in touch with consumer.

- DTH consists of a broadcasting centre, satellite, encoders, multiplexers, modulators andDTH receivers.

- For transmission, KV band transponders in the satellite are necessary.

- Encoder converts audio, video and data signals into the digital format and multiplexermixes these signals. At the receiving end, there will be a small dish antenna(» 45 cm dia) and set-top boxes to decode and view numerous channels.

- One can use the same connection for multiple connections in the same premise providedevery TV set has individual set Top Box

- DTH transmission is digital and offer stereophonic sound effects.

- DTH allows internet access, video conferencing and E-mail

- Cable operator under report the number of customer to broad casters causing huge financialloss to them where as in this case consumers directly pay to the broad caster.

- Since DTH transmission is digital, more channels can be accommodated in the allowedfrequency spectrum.

106106


- STB (JRD) - Digtial Integrated receiver/Decoder

CATV-Cable Television

- CATV involve distributing a number of television channels collected at a centre locationto subscrebers by means of a network of optic fibres/co-axial cables.

- Popular way to interact with world wide websites.

- System of providing TV signals, FM radio programmes and other services to customersvia radio frequency signals.

- Use of different frequencies allows many channels to be distributed through the samecable without seperate wires for each Tuner of the television selects one channel fromthis mixed signal.

CCTV - Closed Circuit Television

- Used in areas of high security viz banks, airports etc.

- Uses television cameras for surveillance

- All components are directly linked via cables or other direct means.

EDUSAT

- Satellite launched by ISRO on 20th September - 2004

- Purpose provide education to all people primarly children who cannot go to schools/colleges.

- Classes conducted by state education boards, NCERTs, CBSE etc.

- Interactive and non-interactive session

- Classes will be conducted in a studio environment and televised to the entire nation.

- To enable this, schools/colleges should have an interactive receiving terminal.

- Education will be available at a fraction of its cost to a large number of students.

- Edusat placed at 36000 km hight geostationary orbit weight-1950 kg and has 5 kv bandtransporders.

107107107


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108108


ADVANCES IN TELEVISIONTECHNOLOGY

8

8.1 Introduction

Television industry is now passing through a period of intensive development effortstowards improvements in transmission and reception techniques. Along with these developmentslot of research has been made to improve in picture resolution and the quality of associatedsound. Innovations towards achieving these include HDTV. Advances in TV technologyincluding plasma TV, LCD TV, TV, Mobile TV, OLED TV, Hollographic TV and DLP arebriefly described in this chapter.

8.2 SyllabusPlasma Television, LCD Television, Project Television, Mobile television, OLEDTelevision, High Definition, Television (HDTV) Hollo graphic Television, DLP (Basicconcepts only)

8.3 Curriculum Objectives8.3.1 To develop a basic idea about modern Television technologies-projection TV, HDTV,

OLED TV, Hollographic TV, mobile TV, Plasma TV etc. through survey, field visit andpreparation of report.

8.3.2 To develop basic idea about the modern display technologies-LCD, TFT and DLP andsubmit an assignment


• Plasma TV

• LCD TV

• HDTV

• Projection TV

• OLED and Hollographic TV

8.5 Learning Activities8.5.1 Give a briefing about the latest television technologies like projection TV, HDTV,

LCDTV, OLEDTV, Hollographic TV, DLP Technology, Plasma TV etc. throughclassroom transaction and with the help of charts. Ask students to collect as much

109109109


information as they could by conducting surveys, referring books or by browsing net.Now tell them to make a detailed report with the help of necessary charts describing thedifferent technologies individually. Also conduct field visits to the nearby show roomsand get familiarized with these developments.

8.6 CE Items

Survey report on different types of TVs Assignment on Activity 8.3.2

8.7 TE Items1 Through advertisement, you may be well aware about the latest technologies of Television

receiver. Can you give a list of the above? Please specify the merits and demerits of each

2 Can you list out the modern display technology used in modern TV Receiver.

Reference1 Modern Television Practice -R.R/Gulathi

2 www. howstuffworks.com

3 www.epanorama.net.

4 www.play-hookey.com

5 www.radiodesign.com

6 www.apple.com

ADDENDUM

Holographic Television

- A projector shines on a thin holographic screen attached to a transparent surface likeglass.

- The effect is an image that appears to float on mid air.

TFT Technology - Thin Film Transistor Technology

- A type of LCD flat panel display screen in which each pixel is controlled by from one tofour transistors.

- TFT technology provides the best resolution for all the flat panel techniques.

- TFT screens are also called as active matrix LEDs.

- Image quality increased by this technology.

DLP Technology- Digital light processing Technology

- Technology developed by Texas

- DLP chip is a reflective surface made of thousands of pixels.

- Small package size

- Produce higher contrast video with deeper black levels.

110110


- Crystal clear clarity

- Reproduces a wide range of colours upto 35 trillion.

OLED - Organic Light Emitting Diode

- These are solid state semi conductor devices that are 100 to 500 nanometers thick orabout 200 times smaller than human chair which emits light with the application ofelectricity through a process called electro phosphoroscence.

- Merits - The plastic/organic layers of OLED are thinner, lighter and more flexible thanthat in an LED or LCD.

- OLED are brighter than LCDs

- OLEDs do not require back lighting like LCDs

- These are easier to produce.

- Large viewing angles are possible like 1700 .

PLASMA TV

- Plasma is a flat light weight surface covered with millions of tiny glass bubbles. Eachbubble contains gas (neon-xenon mixture) like substance called plasma.

- When it is time to display an image signal, a digitally controlled circuit current flowsthrough the screen causing the bubbles give off ultra violet rays. This light courses thephosphor coatings to glow the appropriate colour.

- No need of scanning in TV.

- Plasma TV has a half life of 30,000 to 60,000 hrs.

ie. it will loose approximately 50% of its brightness during that term.

- The gas in plasma TV does not leak. If a pixel fail, it cannot be repaired physically or byrecharging the gas. If large number of pixels go dark, entire panel need to be replaced.

LCD Vs PLASMASl.No. Particular LCD PLASMA

1 Size Thin Thin(32” to 60”) (larger than LCD-13” to 45”)

2 Viewing angle up to 1750 upto 1600

3 Life span Good Good4 Issues - Some times suffer from burn in effect5 Picture Sharp and Wide range of colours and accurate

vibrant colour colour reprodcution6 Brighness Better in bright light In darkness, it produces black spots

conditions. In darkness,it produces very darkcharcoal grey spots

7 Contrast - Greater than LCD8 Weight - Heavier than LCD Fragile than LCD

111111111


HDTV - High Definition TV

- Means broadcast of TV signals with a higher resolution than NTSC/PAL/SECAM

- Is designed as 1080 active line, aspect ratio 16:9

- It is capable of theatre quality audio because it uses the Dolby Digital (AC-3) format tosupport “5.1” surround sound.

- The pixel aspect ratio of High Definition signals is 1.0 or 1 pixel length = 1 pixel width.

- HD signal will deliver either an excellent picture or no picture at all.

- The colours will look more realistic due to their greater bandwidth.

- Standard TV signals broadcast basic stereo audio signals where as Dolby Digital 5.1sound is broad cast along with HDTV video signal with HDTV video signal.

- Minimum vertical resolution - 720 lines.

Projection Television

- Can provide a much bigger picture than CRT sets can.

- It creates a much smaller picture and then uses a beam of light the display that picture ata much larger size.

- 2 types - Front projection and rear projection.

- Front projection uses a projector and a seperate screen. It projects images to the front ofthat screen - as in a movie theatre.

- Rear projection system display images on the back of the screen and the projector iscontained with the TV itself - as in the traditional TV.

112112


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113113113


Part III

Practicals

114114


Practical EvaluationDistribution of scores of P.E

Practical (MRRTV)

Score

Part I Identification of the given components & drawing their symbols 25

Part II Construction of the given circuit and checking its performance 50

Part III Fault analysis of the given faculty equipment and its rectification 40

Part IV Viva 25

Part V Observation/Record book 10

Total 150

Guidelines of practical evaluation

Part I

Item Evaluation points Score

Identification of 5 different Proper identification 5resistorsIdentification of 5 capacitors Proper identification 5(disc, electrolytic, ceramicpolyster)Identification of 2 transistors Proper identification 5and their leadsIdentification of volume control Proper identification 6variable resister Diode, Zenerdiode, LED etc. (4 Nos)Drawing of symbols of all the ( ¼ for each)above components total 4

Part I

Construction of the given circuit


Drawing the circuit diagram Correct symbols & connection 15and labeling the components Neatness, Component values

Setting up the circuit Neatness, Observing O/P, 25measurement of O/P

Recording the voltages & Proper recording 10Computation, plotting graph

Part III

115115115


Fault finding and Rectification


Analysing the given fault Systematic analysis 20

Rectifying the fault i. Systematic working 15ii. rectification 5

Part IV

Viva voce


Viva voce Analytical skill, theoretical 25backing and ability toexplain (Based on vocationalsubject)

Part V


Observation/ Record Practical works 10

Practical examination is conducted for a batch of 8 learners and the duration of examinationis 6 Hrs.

Practical Evaluation

Course :

Class : Year :

SL No. Name Score Total GradeI II III IV V 150

116116


MRR TV- PRACTICAL EXPERIMENTS

Electronic is a field of innovations Taking this into account a humble venture is made inthe is book to cover some ken owned and popular areas of this field but with an effort of notimposing too much strain to the students studying this course. Maintenances and repairs ofelectronic derives is one of the wast job oriented fields in the industry. Even in this fielddevices coming under audio and video Engineering plays a leading role in our day-to-day lifeand so in the practical syllabus, a modest endeavaur is done to deal with the servicing ofinstruments coming under this head.

Trouble shooting and servicing is of course a skill in itself and does not comeautomatically by reading books and remembering circuit alone books give only guidelines tolocate faults. Servicing needs long experience and there are no shoot cuts to it

LIST OF PRACTICAL EXPERIMENTS

1. Amplitude Modulator

2. AM Detector

3. Radio Components Lay out

4. Voltage data collection and tuning of Radio receiver

5. Radio Receiver – Fault finding

6. Tape Recorder – Wiring Diagram- PCB lay out

7. Voltage Data collection of Tape recorder

8. Head adjustment (Azimuth Adjustment )

9. Tape Transport Mechanism.

10. Fault finding in tape recorder

11. P A System Installation

12. Identify and Operate B&W TV controls

13. Identify and assemble a television antenna Yagi Antenna

14. Tracing of power supply/ SMPS stage of B/W TV Receiver.

15. Mounting and testing the picture tube in the cabinet.

16. Tracing and fault finding of the horizontal sub section of a B/W TV receiver

17. Trouble shooting in vertical section of a B/W TV Receiver.

18. Trouble shooting in vertical section of a B&W TV receiver

117117117


19. Trouble shooting in video amplifier stage of a B&W TV. Receiver

20. Trouble shooting in sound section of a B&W TV receiver

21. Trouble shooting in VIF amplifier of a B&W TV receiver

22. Mounting and testing of VJF tuner

23. Identify different stages and main components of a colour TV.

24. Identify and test neck components of a colour picture tube

25. Tracing the SMPS stage of a colour TV receiver

26. Identify controls and sockets of a colour TV and tune program channels.

27. Identify tuner terminals and replace tuners

28. Tracing of video If amplifier section

29. Tracing sound section of a colour TV receiver

30. Tracing sync separator , AFC, and horizontal oscillation

31. Tracing horizontal out put section

32. Tracing vertical sweep section of a colour TV receiver

33. Tracing of chroma section of colour Television

34. Tracing of video output section

35. Identify important parts in to tape pat of VCR/VCP

36. Identify the servo components in VCR/VCP

37. Identify sensors and limit switches of a VCR/VCP

38. General maintenance of a VCR/VCP

39. Identify and aperate the controls of a wonpact disc player

40. Identify different equipmens and modules used in CATV system

41. Installation of CCTV nework

42. Installation, trackin and trpuble sootin of DT receiver

43. Inststallation of TV Tuner card.

118118


EXPERIMENT 1 - AMPLITUDE MODULATOR

Objectives

On completion of this exercise you shall be able to• Construct and test an amplitude modulator

Requirements

Materials/Components Tools/Equipments/Instruments• Refer Fig 1 for component list. • DC power supply: 12V, 100mA -1 No• Bread Board -1 No • Oscilloscope, 20 MHz -1 No• Hook-up wires - as reqd. • Signal generator(AF) -1 No

Procedure

1. Refer the circuit diagram of a simpleamplitude modulator and transmittershown in Fig 1 Make the list of thecomponents required to construct theAM modulator/teansmitter circuit. Getthe list approved by your instruc tor.Collect the components and check thecomponents to confirm its goodworking condition.

2. Construct the circuit and get it checkedby your instructor.

3. Temporaily disconnect the link A-B totest the AF amplifier and oscillatorsections separately.Link A-B disconnects the AB signalinput to the modulator.

4. Power ON DC supply to the circuit and check for RF signal (oscillator output) at the collectorof Q2

5. Tune the core of the oscillator coil to set the frequency of oscillations to around 650 KHz(1.5 Sec) Measure and record the frequency and amplitude of RF oscillation.

6. Feed a 1KHz AF Signal at the AF input and check for presence of AF at the collector of Q2

7. Connect the link A-B disconnected at step 3.8. Feed a signal of 1 KHz at the AF input of the modulator.9. Observe the wave-form at the output of the modulator using a CRO.10. Adjust the output level of the AF signal generators such that the modulated output is

similiar to that shown in Fig.211. Referring to Fig2, measure and record

the level of Vmax and Vmin.12. From the recorded reading of V max

and Vmin calculate and record the depthof modulation of modulationindex(m) and prcentage of modulationm% using the for mula.

119119119


Dept of modulationPrecentage of modulation m% = m x100.The termm indicates the level towhich the RF is modulated. Themaximum value of m can b E 1.

13. Get the modulated output wave formand your readings checked by yourinstructor.

14. Increase the output level of the AF signal generator slowly till the value of Vmin = 0 asshown in Fig 3.This is the condition of 100% modulation or m=1.

15. Disconnect the signal generator and connect a crystal or a dynamic microphone at the AFinput terminals of the modulator.

16. Speak into the microphone and observe the modulated output wave -form.

120120


EXPERIMENT 2 - A.M.DETECTOR

Objectives

1 To Understand the function/ working of each component in the circuit

2 To observe /Measure both input and output ware forms.

Requirement

Materials/Components Tools/Equipments/Instruments

• Refer Fig 1 for component list. • DC power supply: 12V, 1

• Refer fig for component list • C RO

• Bread Board – 1 No. • Digital Multi Meter

• Hook up Wirer - as required

Procedure

1. Refer the circuit diagram of a simple diode detector as shown in fig.

2. Check all components and rig up the circuit

3. Apply A.M. Modulated signal to the circuit and observe the output CRO.

4. Get the working of the detector checked

121121121


EXPERIMENT 3 - RADIO COMPONENT LAY OUT

Objectives

1 To know the component lay out of radio Rx- PCB2 To sketch the layout3 To identify the stages of radio Rx.4 To identify and familiarize the various components on PCB.

Requirements

Radio receiver , screw driver set

CIRCUITIDEA: -

Lay out is the component side view of the PCB, arranged in a systematic order . Thelayout desining is in such a way as to reduce circuit complexity and the various stages of the

radio receiver circuit and we become familiar whith components used in radio and its locations

SAMPLE LAY OUT

SW.ANTENNACOIL TRTMMER

SW MW

ANTENNA COILM.W.

BAND SWITCH 220 µF CAPACI-TOR

AFTRANSISTER

A1015V

RFSTAGE

MW OSC r COIL

SW OSC r COIL

BF 194GANG 2 J

DRIVER TRANSFORMER

BC 548AFSTAGE5 µF 220µ

FAVC

VOLUMECONTROL

AF Ist IFT II nd IFT IIIrd IFT

IF STAGE BF195C BF 195 D

DETEC-TORSTAGE

122122


Procedure1. Collect radio receiver and tools2. Open the back cover of radio receiver whith screw driver3. Observe the wiring and locatins of various component4. Carefully take out the PCB from the cabinet receiver PCB6. Identify the various stages and components of receiver PCB7. Carefully fix the PCB on the cabinet8. Replace the back cover and tight it9. Return the radio receiver to the lab.

Cir

cuit

dia

gram

of R

adio

Rec

eive

r

123123123


EXPERIMENT 4 - VOLTAGE DATA COLLECTION AND TUNING OF RADIO RECEIVER

Objectives

On completion of this experiment you shall able to

1. To know the circuit of radio receiver2. To identify the test points on PCB3. To measure and record various voltages of active components.4. To perform the function of tuning different Stations


• Radio Receiver • Screw driver

• Tracing Sheet/ graph sheet • Digital Multimeter

• Circuit diagram of your radio receiver • R.F. Generator,6/12 power supply, loud

speaker

Hints

Students may be divided in to batches of 5/6 each to perform the lab work and ask them toprepare a chart showing voltage levels at different points, which will be helpful for faultanalysis

Procedure1. Collect Radio receiver and tools and equipments from the laboratory2. Set different frequencies on RF generator and connect it to the Antenna termmals of SHR.

Now tune the set for a proper sound in the loud speaker3. Open the back cover with proper tools4. Locate various Stage and active components5 Identify the test points6,. Measure various voltages at different test points by using digital Multimeter ( In D.C.

mode)7. Tabulate these readings and compare with standard voltage

Tabulation Column

Stage Transistor E Volts B Volts C Volts

RF

IF

Driver

AF

124124


↑

↓

↑↑ ↑ ↑

2 V↓

4V↓

400mV

↓ 2800mV

↓

RFAMPLIFIER

ANDMIXER

#

$

#

!

#

$810 mV

SIGNAL ANALYSIS OF RADIO RECEIVER

I FAMPLIFIER

AF AMPLIFIER

DETECTOR

A .V. CLOCAL

OSCILLA-TOR

L S

125125125


EXPERIMENT 5 - RADIO RECEIVER FAULT FINDING

Objectives1 To know the concept of fault finding2 To identify the symptom of fault3 To locate the faulty stage of radio Rx logically4 To rectify the fault

Circuit are

The methods applied to locate the faulty stage of a radio receiver are personal observation

signal injection and signal tracing. First find out what the receiver really like by listeningcheck. From the symptom identify the faulty stage by logical approach and rectify the fault

using voltage data and referring circuit.

Tools, euipments, materials

Screw driver , soldering iron , DMM, CRO, AF- RF signal generator, Radio receiver

assorted components etc.

Prcedure1. Collect the faulty receiver and equipments3. Identify the symptoms of given faulty receiver.A. SYMPTOM :- Dead Receiver

Additional Symptom :- No sound , not even hissing soundOperating steps:-1 Switch on the receiver and confirmed the complaint.2 Identified the possible causes for the complaint.3 Checked the power supply stage and found that it is faulty.4. Check each components and connections and confirmed that transformer primary winding

was open .5. Replaced the transformer with new one.6. Tested the receiver for its working condition. DEAD RECEIVER

DEFECTIVEPOWER SUPPLY

TRANSFORMERPRIMARY WINDING

OPEN

REPLACED NEW ONESET OK

MAINSCORD

OKSWITCH

A

83 6

6

6

126126


B. SYMPTOM :-Low Audio output with volume control Maxpos Additional Symptom:- Distortion in theoutput

Operating Steps

1. Identified the possible causes for the complaint2. Check the power supply stage and found ok.3. Checked the loud speaker and found ok4. Checked the voltage at the loud speaker point in AF stage and found ok.5. Checked the output transistors and confirmed that one is open6. Replaced the transistor with new one and tested the working condition of receiver.

C. SYMPTOM:- Hissing noise in output

Operating Steps

1 Identified the possible causes for the complaint2 Checked the AF stage and found OK3 Checked the detector stage and formd detector diode open4. Replaced the diode and checkd the working condition

6

6

LOW AUDIO OUTPUT WITH VOLUME CONTROL MAXIMUM

DEFECTIVEAF STAGE

1. POWER SUPPLY2. LOUD SPEAKER3 O/P ELECTROLYTiC CAPACITOR ( AF STAGE )

OK

OUT PUTTRANSISTOR

OPEN


6

B

6

HISSING NOISE IN OUTPUT

DEFECTIVEDETECTOR STAGE

AFSTAGE OK

DETECTOR DIODEOPEN


6

6

6

6

C

127127127


D SYMPTOM:- Some station picked up at two places

Operating steps

1. Identified the possible causes for the comlaint2. Checked the IF stage found that IFTs are misaligned3. Aligned the IFTs and put soft wax on IFTs4. Checked the working condition

E. SYMPOM : Station not picked up at either end of band

Operating steps

1. Identified the possible cause for the complaint2. Checked the IF stage and found ok3. Checked the converter stage and found the RF transistor defective4 Replaced the defective transistor with new one and tested the working condition5. Carry/out the general cleaning of the receiver after servicing6. Replaced the cabinet if it was removed for s servicing7. Returned the radio & materials to the store.

Skill Table

Sl.No. Skills Score1. Identification of symptom2. Location of faulty stage3. Rectification of faults in Rx

E

q

q

q

q

STATION NOT PICKED UP AT LOVER END OF BAND

DEFECTIVECONVERTER

STAGE

RF TRANSISTOROPEN

REPLACED NEW ONE

IF - OKSTAGE

MISALIGNED IFT

ALIGNED IFTsSET OK

q

q

D

SOME STATION PICKED UP AT TWO PLACES

128128


EXPERIMENT 6 - TAPE RECORDER WIRING DIAGRAM PCB LAY OUT

Objectives

1. To identify and familiarize parts of tape recorder:2. To identify the stage of tape recorder3. To. Draw the s layout –wiring diagram

Hints : Collect the lay out of the tape recorder and issue before starting the experiment

Circuit Idea

Tape recorders are the simplest and most commonly used device next to Radio . The tape

recorders are mainly used by music lovers, journalists , educationalists, ete. It is a combination

of mechanical assembly and electrical / electronics units . The know how of wiring diagramand components layout is essential for servicing purposes. By this we can identify the

components ,R/P switches , and stage of tape recorder and know the connection terminals of

the components out side the PCB.

Equipments, Tools & Materials

Tape recorde, Screw driver, tweezers

Procedure

1. Collect tape recorder and tools2. Open the back cover with screw driver of proper size3. Observe the wiring and locations of various components in the PCB and outside the PCB.4. Carefully take out the PCB from the cabinet5. Sketch the PCB layout of tape recorder6. Sketch the wiring diagram also.7. Carefully fix the PCB and mechanical assembly on the cabenet.8. Replace the back cover and tight it .

129129129


EXPERIMENT 7 - VOLTAGE DATA COLLECTION OF THE RECORDERObjectives

1. To know the circuit of electronic section of tape recorder2. To identify the test points on PCB.3 To measure and record voltage data.CUIRCUIT IDEA:-

The know how of the voltage data of electronic section is required for fault finding

purposes. Voltage data collection can be performed in the electronic circuit of tape recorderwhich includes power supply , Pte-amp, equalizer/,driver and o/p stage and H F bias oscillator.

During recoding mode , the play back section remains inoperative . During play back recording

section remains inoperative.


Tape recorder , Screw driver, Digital multimeter , probes, power supply, cassette

Procedure

1. Collect the tape recorder from the lab.2. Open the back cover with proper screw diver3. Locate the various stages and active components.4. Identify the lest points.5. Select DMM with sharp probes6. Measure various voltage at different test point in both playback and record mode.7. Tabulate these readings and compare with standard voltage.8. Replace the back cover and tight it.9. Return the tool and tape recorder to labTabulation Column (sample)Component Play Back Mode Record modeTransistor Emitter Base Collector Emitter Base collectorBC 149 BBC 148 BBC 148 CIC TBA 820 Pin No. Voltage Pin No. Voltage

1 12 23 34 45 56 67 78 8

Recording bias in dc (Record Head) =Erase bias in dc (erase head) =

130130


EXPERIMENT 8 - HEAD ADJUSTMENT (AZIMUTH ADJUSTMENT)

Objectives

1. To know the idea of head adjustment (azimuth adjustment)2. To identify the head adjustment point.3. To perform the head adjustment (Azimuth adjustment)4. To verify the effect of head adjustment.

Basic Idea

The misalignment of head has the effect of increasing the effective gap of the playbackhead. This causes reduction in output at high frequencies. The recording /play back heads are

mounted in a way which permits alignment of the azimuth. The azimuth of the head can be

adjusted by trimming the azimuth adjustment screw. The head can be aligned with a specialcassette test tape . These test tapes are precision recorded on cassette tape recorders , the

heads of which are aligned very accurately. The frequency recorder on these cassettes for

alignment of the head is about 4 KHz.


The recorder , screw driver set , cassette, Multimeter.

Operating Steps

1. Place the test cassette tape on the recorder.2. Connect an output meter or multimeter on a range. 2.5 V AC3. Set the volume control to mid way4. Play back the head alignment part of tape . If necessary adjust the volume control for a

convenient reading on meter.5 Adjust the head azimuth adjustment screw for maximum reading on meter ( by turning

screw slowly side till the output increases to one side and then to the other6 If head has been replaced , the azimuth may be much out . In this case azimuth should be

adjusted till a clear defined peak is obtained and the 0utput reaches a maximum value.Skill Table

Sl.No. Skills Score1. Identification of head adjustment screw2. Handling of head & method of operation3. Verification of head adjustment

131131131


132132


EXPERIMENT 9 - TAPE TRANSPORT MECHANISM

Objectives

1. To know the tape transport mechanism .2. To identify the main parts of transport mechanism3. To know the function and necessity of each parts4. To sketch the tape transport diagram.

Basic Idea

Function of the transport mechanism in tape recorder is to roll the tape from one side toother side of cassette and vise versa as and when required , ensuring constant and swift speed

of tape. The tape mechanism also enables the tape to be wound quickly on either side red for

fast forward and rewind operations . Main parts are motor , Belt , Flywheel,Capstan , pinchroller and idles wheel / idler pulley/ tension pulley. The motor drives the tape transport parts.

The fly wheel is made of material having more weight and so it rotates in constant and swift

speed without flutters . Capstan and pinch roller provides constant speed of the tape . Idlerwheel /pulley/ tension pulley are used to move the tape in either directions .The different

modes are record, play back, F F, and rewind . Variation slow speed causes Vow effect

variation of high & speed causes FLUTTER effect.


Tape recorder , screw driver , tweezers ,

133133133


Procedure

1. Collect tape recorder2. Open the back cover using appropriate screw driver3. Unscrew the related screw those who holds the mechanism to the cabinate4. ‘Remove the mechanism out of the cabinet.5. See the mechanism from all sides and locate the important parts such as motor, belt, heads,

leaf, switch, Fly wheel etc.6. Press PLAY button and observe the respective pulleys engaged for play mode and draw the

transport mechanism.7. Similarly observe the arrangement of tape transport mechanism for RECORD, FF and REW

mode.8. Fix the mechanism back to the body and put the cover and return it to lab

Skill TableSl.No. Skills Score1. Identification of main parts of transport mechanism2. Verification of roles of each parts in various modes3. Sketching of transport mechanism

134134


EXPERIMENT 10 - FAULT FINDING IN TAPE RECORDER

Objectives

1. To know the symptoms in tape recorder2. To analyse the causes for symptom3. To know the shortest path for rectifying the defect using service flow sequence or trouble

shooting chart4. To verify each causes and rectify the defectBasic idea

When a tape recorder is defective , at first it is required to determine the nature of fault init. When it is switched ‘ON’ it shows a symptom by which we can identify whether it’s mechanical

section is faulty or electronic section is faulty or both can be suspected. From the observed

symptom applying the knowledge of working of tape recorder. The faulty area can be thoughtof and from further tests we can identify the defective component. It is to be analysed the cause

for defect before replacing the defective component.


Tweezers, wire stripper, wires, DMM, faulty tape recorder, servicing components

Operating Steps

1. Collect the faulty tape recorder2. Identify the symptom of tape recorder

1 SYMPTOM:- NO TAPE MOVEMENT

Additional Symptom:- when v/c put to maxposition, a small hissing sound is heard.

1. Remove the back cover2. Identify the possiblecauses3. Checked motor rotation, found okay.4. Checked Fly wheel rotation, found not

rotating5. Belt found broken, replaced, set okay

(2) SYMPTOM:- NO SOUND

Additional symptom:- Tape movement okay,no recording

1. Checked loudspeaker, okay.2. Checked power ampr stage, okay3. Checked driver stage, transistor defective

(base emitter open)4. Replaced transistor, tape recorder okay

q q

SYMPTOM 1

NO TAPE MOVEMENT

FLYWHEEL

c h e c k e dr o t a t i o n ,

o k a y

checked rotation, noto k

checked belt, brokenreplaced belt

MOTOR

checked found defective(BC148 base-emitter open)Replaced transistor BC 148set OK

SYMPTOM 2

NO SOUND

LOUD SPEAKER

POWER AMPr

DRIVER STAGE

DRIVER TRANSISTOR

checked OK

checked OK

checked ,q

q

q

q

found defective

135135135


(3) SYMPTOM:- TAPE SPEEDNOT CONSTANT

1. Checked pinch holler surface forits sticky nature, found defective.

2. Replaced pinch holler, taperecorder oky

(4) SYMPTOM:LOW VOLUMEOUT PUT

1 Checked adjustment of head ,found defective (misadjustment )

2. Adjusted the head, set okaySwitch off the tape recorder andreturn materials to labe

checked OKReplaced pinch roller

SYMPTOM 3

checked,found stickn(defective)

q

q

SPRING TENSION OFPINCH ROLLER

PINCH ROLLER

SYMPTOM : TAPE SPEEDNOT CONSTANT

SYMPTOM 4

checked, foundMisadjustedAdjusted headSet OK

q

HEADP- MISADJUSTNENT

SYMPTOM : LOW VOLIME

Skill TableSl.No. Skills Score1. Identification of symptom2. Location of faulty stage3 Rectification of fault

136136


EXPERIMENT 11 - P A SYSTEM INSTALLATION

Objectives

1. To become familiar with PA System and its control2. To know the installation of PA System.3. To operate its control and observe the effects.

Circuit Idea

Public address (PA) system is an electroaccoustic system, in which sound is first converted

into electrical signal (audio) by microphones, and then audio signals are processed and amplifiedand finally are fed to loud speakers which convert them back to sound. The amplified sound

provides confortable listerning to large gatherings as in public meetings, sports concerts,

functions or to isolated locations as at railway station , airports etc.. A number of microphoneor loudspeakers are be simultamosry operated with a PA amplifier. A speaker type of transformer

(LMT) is used for coupling the loudspeakers to the amplifier


PA amplifier microphones, loudspeaker , conecting cables, wires, screwdriver etc..

M

Procedure

1. Collect the equipments form store.2. Refer the manual of PA amplifier identify each connector3. Connect the given microphone & loud speaker to the PA and with suitable position.4. Switch on the PA amplifier & microphone.5. Adjust the volume control of each microphone

137137137


6. Adjust the overall volume level with Master control at about ‘6’ to ‘8’ position.7. Adjust the tonal quality as per the requirement by using bass & Treble controls.8. Check the sound volume & quality with different inputs.9. Switch off equipments.10. Collect the Information regarding PA installation to public meeting, auditorium etc...

PRECAUTIONS TO BE TAKEN WHILE INSTALLING PA SYSTEM

1. Acconstic feedback should not occur2. Amplifier’s audio output power should be suffieiant and should be informly divided by

using several loud speakers.3. Excessive reverberation should be reduced by appropriate furnishing and proper place

ment of loud speakers.4. Loud speakers should be properly oriented to direct the sound to the audience.5. Noise cancelling microphones and treble boost in amplifaier should be used where ambient

noise is high as in sports.6. Amplifier should have automatic level limiter to reduce distortion due to over loading.7. Microphones should be carefully selected to suit the programme.8. Matching of impedance between microphone and amplifier input and between amplifier

output and loud speakers is essential.9. Microphone leads should be isolated from a.c leads to iliminate chance of picking up a.c.hum.10. Radio fequency pich-up should not occur.

BACK VIEW (Sample)

Skill TableSl.No. Skills Score1. PA sytem Installition2. Setting of different control3. Handly of equipement

138138


EXPERIMENT 12 - IDENTIFY AND OPERATE B & W TV CONTROLS

Objectives

On completion of this excercise you shall be able to* Locate and identify controls on the front panel and other terminal sockets of a B&W TV set* Tune the B&W TV receiver for different aired TV Channels* Adjust controls for better picture and sound* Use pattern generator to adjust TV controls for optimum brightnness and contrast* Use pattern generator to identify linearity defects on the TV Screen.* Operate B & W Television using remote control.

Requirements


• B&W TV receiver of different -1 Set/batch make with/without remote

• RF cable (direct probe)- 4 cables

• Trainees tool kit - 1 set

Note: Minimum of four B&W TV sets of different makes shall be used for this exercise.

A batch of 4 trainees shall work on each TV at a time.

Hint to Instructor:1. Instructor shall cover all the identification marks, names of the controls & sockets and

provide labels (A,B.C......or 1,2,3......) for the same before the start of the exercise so thatthe trainees can perform the identification exercise.

2. Instructor shall give four Xerox copies of operating Instruction sheets of the TV per batchof trainees. And he shall demonstrate the functions of the controls after comple tion oftask1.

3. Demonstrate the procedure for tuning with turret type tuner and Electronic tuner TV forreceiving the local TV channel.

4. Demonstrate the operation of remote control unit

Procedure

TASK 1 - Identify external controls and sockets of a B&W TV set.

1. Select any one of the labelled B&W TV and Record the name and its function on the O&Tsheet Table 1 and 2 by referring to the given TV operating manual.

2. Repeat step 1 for all other labels.3. Get your work checked by the instructor.4. Connect the antenna to the RF input TV and switch ON, adjust the brightness and contrast

control to the middle position.5. Tune the receiver to the available on the air programme (local TV channel) as demon

strated by your instructor)6. Repeat step 5 for different channels.

139139139


TASK 2: Identify Linearlty defects on the TV screen Using pattern generator.

1. In the pattern generator given, locate, identify and record the input, output controls andtheir functions in table 3.

2. List out the patterns available in the given pattern generator in Table 4.3. Connect the output of the pattern generator to the antenna input of B & W TV, as demonstarted

by your instructor.4. Power ON pattern generator, Select channel 4 in TV receiver and tune it for clear pattern.5. Select gray scale pattern.6. Adjust brightness, contrast and fine tune controls of TV to get distinguish visible gray scale

pattern.7. Write down the number gray scales in O&T sheet.8. Select horizontal pattern in the pattern generator.9. Check it there are any defects in Linearity. Record defects observed in Table 6.

Identification of defect was demonstated by instructor.If any doubt consult your instructor.

10. Repeat steps 8 and 9 by selecting other patterns available in the pattern in the pattern generator.11. Get your work checked by your instructor.

TASK 3:- Identify the different controls/ functions available on the remote control unit of a

TV set.

1. Refer the remote control manual and identify the location and functions of different controlbuttons as identified in Task 1. Record the positions of the buttons on the O&T sheet.

2. Operate different controls of TV through the remote control unit and set brightness, contrastand sound to required level.

3. Get your work checked by instructor.4. Vary the distance and angle between the remote control and the TV and operate the remote

control unit to find the approximate maximum distance in which the remote control workeffectively. Record the distance and the angle in the O&T sheet.

5. Get your work checked by instructor.6. Switch OFF the TV and remove antenna connection.

140140


EXPERIMENT 13 - IDENTIFY AND ASSEMBLE A TELEVISION ANTENNA

Objectives

On completion of this excercise you shall be able to* Identify the TV antenna elements* Assemble the antenna elements* Terminate Wires from the dipole* Set the orientation of the antenna.

Requirements


• TV antenna 3 Element type - 2 Nos • Trainees Tool Kit

• TV antenna 5 Element type - 2 Nos • Spanners (Required size)- 4Sets.

• Antenna cable (flat/ribbon) - 4 Mts. • Cutting pliers -4 Nos

• Balloon transformer - 4 Mts • Measuring tape (1 mtr) - 4 Nos

• Insulation tape - as reqd

Procedure

TASk 1:- Identification of TV antenna Elements

Hints to Instructor:

1. At least one TV antenna should be provided to a group of 4 trainees.2. Provide the TV antenna of the trainees without ‘support pole’ for easy

handling.3. Label the antenna elements before the exercise.4. All the trainees should do identification on both 3 and 5 element antenna.

1. Record the type of antenna in the O&T sheet based on the number of elements.2. Select one of the label from the given antenna, identify the name and record in the O&T

sheet.3. Measure and record the length of the identified element in the O&T sheet.4. Repeat step 2 and 3 for other labels.5. Measure and record the distance between the elements in the record sheet through a rough

sketch.6. Get your work checked by your instructor.7. Repeat step 1 to 6 for the other type of antenna.)

141141141


TASK2: Assemble a TV antenna


1. Demonstrate the method of assembling the antenna elements for 5 elementand 3 element antennas.

2. Each batch should assemble 5 element as well as 3 element antennas

1. Visually inspect the given TV antenna, bolt & nuts, for any rusting, apply rust removeror kerosene in case of any rust, and allow five to ten minutes for the solution to penetrate.

2. Identify and record the type of antenna elements given to you form O&T sheet.3. Assemble the given antenna referring to the details availabe in your O&T shhet.4. Get the work checked by your instructor.5. Clean the end of the dipole by Scrapping/applying emery sheet.6. Strip the given antenna wire ends to 10 cm, and connect to dipole as shown in fig.1.

7. Apply a PVC insulation tape over the wire-dipole joints as shown in fig2.

8. Attach the terminal box to the dipole as demonstarted by your instructor.9. Get the work checked by your instructor.10. Fix the antenna to the support pole and fix the antenna unit temporarily in the side of work

bench or any where outside.The assembled antenna fixed with support pole may be installed in the top of any buildingavailabel for mare realistic practice.

11. Fix the antenna in the direction such that the director faces the direction of the TV tower.12. Connect the antenna cable to a TV and tune the TV for the Aired program.13. Adjust the antenna direction slightly (left and right) till a clear picture is obtained.14. Get the work checked by your instructor.

142142


EXPERIMENT 14 - TRACING OF POWER SUPPLY/SMPS STAGE OF B/W TV RECEIVER

Objectives

On completion of this exercise you shall be able to* Identify the components/devices and draw their corresponding symbols* Trace out the circuit diagram of given SMPs stage of a B/W TV* Rearrange the traced circuit in sequence from input to output.* Identify and measure voltage at test points.


* TV receiver - 1 No (batch of 4 trainees) * Trainee’s tool kit - 4 set. * Table lamp - 1 No. * magnifying lens - 1 No.

Hints to Instructor

1. The instructor shall keep a commercially available circuit/service manual for the TV modelsavailable in the LAB. If the circuit given in this materials is different to that of your TV.

2. Make copies of the circuit diagram in stages as given in this material for the trainees toperform this exercise. Issue the actual circuits only after the trainee completes the roughtracing.

3. If spare boards of the TV is available it may be given for tracing and only the voltagemeasurement can be taken from the working TV.

Precautions

1. Keep the TV OFF when performing the tracing task.2. While tracing the circuit never bend the component or force wires.3. If any wire gets cut during the tracing work, immediately inform the instructor and get it

resoldered correctly.

Procedure

1. Remove the back cover of the TV receiver and unscrew the chaissis / mains PCB fittingscrews, Keep all screws, nut fateners etc, safetly in a transparent cover.

2 Detach the connectors wherever possible and take the PCB out of the cabinet without in astretching the soldered wires too much.Label the connectors for easy identification

3. Position the PCB such that all component side faces towards you.Provide a support for the stable positioning of the PCB.

4. Locate all the components of SMPS stage on PCB referring to the lesson, record their symbolson the place marked for rough sketch, in the O&T sheet as laid out in the PCB.

5. Count the toatal number of each category of component, and enter in the O&T sheet.6. Keep a lamp at the backside of the PCB.

Use a table lamp or a test lamp. Do not keep the bulb very close to the PCB. Do not keepthe bulb coninuously ON for more than 10 to 15 minutes to avoid PCB getting heated up.

143143143


7. Start the tracing work of the circuit from mains cord, to dc outputterminals of SMPS bymarking the links/connections between component symbols drawn on the O&T sheet.

8. Referring to the circuit diagram of that brand/model TV obtained from your instructor,rearrange the traced out circuit in sequence from input to output.

9. Mark the locations of the test points on the rough sketch of the traced circuit and on therackside of the PCB with a sketch pen.

10. Record the specified voltage for the test points in table 2 of record sheet referring circuitdiagram.

11. Get the traced circuit checked by your instructor.12. Re-fix the connectors and place the PCB conveniently in position that so the trackside of

the PCB is faces you.13. Switch on the TV in the presence of your instructor. Note down the symptoms in the O&T

sheet.Beaware that you are working in a very high voltage enviornment.Do not measure voltage other than places marked.

14. Measure the voltage on the test points using Multimeter and record in table 2 of O&T sheet.

144144


EXPERIMENT 15 - MOUNTING AND TESTING THE PICTURE TUBE IN THE CABINET

Objectives

On completion of this exercise you shall be able to* Mount the picture tube into the cabinet.* Test the picture tube* Connect the picture tube, PCB, yoke, and EHT* Troubleshoot the picture tube faults.

Materials/ Components

* Available cabinet suitable for 20” picture tube - 1 No* 20” picture tube - 1 NoHints to Instructor: The instructor shall demonstrate the picture tube mounting and detachingprocedures using a working TV receiver.

Procedure

TASK 1:- Detaching and mounting the picture tube

1. As demonstrated by your instructor detach and mount the picture tube from/ to the cabinet.2. Get your work checked by your instructor.Note:1. Do not hold picture tube on neck side.2. Do not rest the picture tube on neck (side wise)

TASK 2:- Make connections to the picture tube

1. Fix the yoke at the neck of picture tube2. With reference to the circuit diagram connect the picture tube base socket to the picture

tube base pins.3. Make horizontal and vertical connections to yoke4. Fix the EHT connection to the EHT soket in the picture tube.5. Fix earth shield connections over the graphite coating outside surface of the glass neck.6. Get your connections checked by the instructor.7. Switch ON the TV set. Adjust the controls to get clear picture and noise free sound.8. Measure and note the voltages at all the pins of picture tube in O&T sheet.

Refer circuit for various voltages to be availabe are CRT pins for the safety of the meterand self. Do not try to measure the EHT voltage.

9. Switch off TV set.10. Get your work checked by instructor.11. Discharge the stray capacitance of the picture tube.

145145145


Picture tube specifications

500C1P 4, 590C1 P4,610C1P 4

pins

1. Filament 1&8

2. Cathode 7

3. Control grid 2&6

4. Accelarating anode 3

5. Focussing 4

6. No Connection 5

310C1P4, 470 C1P 4

pins

1. Filament 3&4

2. Cathode 2

3. Control grid 5&1

4. Accelarating anode 6

5. Focussing 7

6. No Connection 8

TASK 3:- Rectify the simulated fault in the picture tube control circuit of the B & W TVreceiver

1. Switch ON the set to confirm the informed complaint. Record both the informed complaint and the identified complaint in O&T sheet.

2. Identify the defect causing the complaint. Refer problem tree discussed in lesson for earlyidentification of the defect.

3. Record the identified defect. Refer troubeshooting chart for the remedial measures.4. Service the defect. Test the set for its satisfactory working.

If the complaint is not rectified/if complaint other than informed exists consult your instructor.5. Record the remedial action taken during servicing along with the components replaced if

any in the O&T sheet.6. Get your work checked by your instructor.

1

2

3

45

6

7

8

1

2

3

45

6

7

8

146146


TROUBLESHOOTING CHART

Sl Observable Additional Probable Causes Remedial measures No symptom symptom defect(s) reasons

1 Curved raster Picture ok Improper Yoke fixing Check and correct the(Neck shadow) Sound ok Positioning of Screws position of the

Yoke loosened Yoke and tighten thescrews

2 Diagonal raster Picture ok Tilted yake Mispositioning Turn the yoke to getSound ok of yoke correct raster.

3 Picture upside Picture, Upside down Mispositioning Check and correct thedown raster ok tilted yoke of yoke yoke position

Connections Wrong Replace the wiresto Vertical connections correctlydeflection coilreversed

4. Pin cushion Picture ok Misaligned pin Displaced pin Check and correct theeffect (raster sound ok cushion magnet cushion magnet position

distortion

5 Blackended Sound ok Misaligned ring Displaced ring Check and correct thecorner raster not Picture visible magnets Magnets positionavailable at thecorner (rasterdistortion)

6 EHT arcing Noise at the Interpol EHT EHT connector Check and tighten theEHT loose contact EHT connector.

7 Lateral inverted Raster Hoz deflection Wrong Rectifypicture sound ok coil connection connection

intercharged

147147147


EXPERIMENT 16 - TRACING AND FAULT FINDING OF THE HORIZONTAL SUB SECTIONOF A B & W TV RECEIVER

ObjectivesOn completion of this exercise you shall be able to

* Identify the components / devices of the horizontal sub section and draw their corresponding symbols

* Trace the circuit diagram of the horizontal sub section of given B&W TV* Rearrange the traced circuit in sequence from input to output* Rectify the simulated fault in the horizontal sub section.

Requirements

Materials/Components Tools/Equipments/Instruments• B&W TV receiver - 1No • Trainees kit - 1 No

• CRO 15 MHz - 1NoHints to Instructor1 The instructor shall make available circuit/service manual for the B & W TVs models used

in this exercise.2 Make copies of the circuit diagram of different stages (horizontal sub section for this exercise)

for the traniees to perform this exercise and subsequent exercise.3. Instead of asking the trainees to open the B&W TV and trace the circuit, if spare boards of

the same B&W TV is available, the spare boards can be given for tracing practice.4. Demonstrate the method of pulling out the PCB from the TV and positioning the main PCB

suitable for tracing.5. The instructor shall simulate certain faults in the horizontal sub section of the TV receiver

set, for the trainees to carryout fault finding and servicing. rafer problem tree for simulatingdefects.

6. If the trainee is able to trouble shoot created defect early, create another defect and ask thetrainee to service that and then other defect and so on.

Procedure

TASK 1:- Identification of components and Tracing the circuit1. Remove the back cover of the given B&W TV receiver. As demonstrated by your instructor,

detach the connectors from the PCB such that the PCB can be pulled out of the cabineteasily for the purpose of circuit tracing. Position the PCB is such that the compo nent side ofthe PCB is facing you. Get it checked by instructor.Keep all screws, nut fateners etc, saftely in a transparent cover, Label all the detachedonnectors/ Wires so that it is easy while reconnecting them back in their place.

2. Referring to the circuit schematic of the horizontal sub section, locate the components ofhorizontal sub section on PCB. Record the identified components symbols in the O&Tsheet (similar to the PCB layout) in the place marked as “Space for rough sketch of thecomponent layout with tracks”.

3. Count the local number of each category of component (like resistor, transistor etc.) Identifiedin horizontal sub section and enter in the O&T sheet.

148148


4. Get the rough sketch of traced components of the horizontal sub section cheked by theinstructor.

5. Place a table lamp of around 40W at the back side (Solder side) of the PCB.DON’T keep thebulb very close to the PCB as his may heat-up the components. DON’T keep the bulbcontinuously ON for more than 10 to 15 minutes to avoid PCB getting heated up.

6. Trace the of horizontal sub section by marking the links/and connections between component symbols , drawn on the O&T sheet at step 2.

7. Referring to the circuit diagram of the horizontal sub section from the lesson or given toyou by your instructor rearrange and redraw the traced circuit in the O&T sheet in the spacemarked as “Space for redrawing the final circuit diagram of the traced circuit.

8. Get the traced circuit checked by your instructorO&T sheet -observation and tabulation sheet.

TASK 2:- Rectifying the aimulated fault in the horizontal sub section of the given faulty TV

receiver

1. Switch ON the TV set to confirm the informed complaint. Record both the informed complaintand the identified complaint in the sheet.

2. Record the identified defect. Refer trouble shooting chart for the remedial measures.3. Service the defect. Test the stage for its satisfactory working.4. record the remedial action taken during servicing along with the components replaced if

any, in the O&T sheet.5. Get your work checked by your instructor.

149149149


Sl Observable Additional Probable Causes/ Remedial measures No Symptom sympton defect(s) reasons

1 Bright vertical Sound ok No deflection C522(220kpf) Test and replace C522,line current flow open and horizontal deflection

through horizontal coil and connectinghorizontal deflection coil wiresdeflection open Horizontalcoil deflection coil

connectingwires open.

2 Horizontal Picture ok Incorrect H.hold control Test and replace H.hold controlrolling Sound ok horizontal defective VR501.(diagonal frequency Incorrect Reset the VR501 to lockrolling) setting of diagonal rolling.

H.hold controlVR501.

Loss of Defective R507 Check and replaceH.sync R508,C505,andSignal C504.

Loss of R514 27K Check and replacefeeback from C507-220kpfLOT No voltage atpin Check voltage with the

no.5 of CA920. data given

3 Horizontal Sound ok Defective Due to Check and replace Q503.fold over Picture horizontal aging

visible transistorQ503BU505

Defective line Due to repalce new LOToutput excessivetransformer heat produce

inter oscillation inter oscillation

Defective by Leaky C515 Check and replacepass 100 µFcapacitor C515 100.

Defective R526 open Check and replace R526.wave shaping due to longcomponent long use.R526.

150150


Objectives

On completion of this exercise you shall be able to* Identify the components/ devices and draw their corresponding symbols.* Trace the circuit diagram of horizontal output section of given reference B&W TV* Rearrange the traced circuit in sequence from input to output* Rectify the simulated fault in the horizontal output section.

Requirements

Materials/Components Tools/Equipments/Instruments• B&W TV receiver - 1 No/Batch

• Traniees kit - 1 No

• CRO 15 MHz - 1 No


1. The instructor shall make available circuit/service manual for the B&W Tvs models used inthis exercise.

2. Make copies of the circuit diagram of different stages (horizontal output section for thisexercise) for the trainees to perform this exercise and subsequent exercise.

3. Instead of asking the trainees to open the B&W TV and trace the circuit, if spare boards ofthe same B&W TV are available, the spare boards can be given for tracing practice.

4. Demonstrate the method of pulling out the PCB from the TV and positioning the main PCBsuitable for tracing.

5. The instructor shall simulate certain faults in the horizontal output section of the TV receiverset, for the trainees to carryout fault finding and servicing. Refer problem tree for simulatingdefects.

6. If the trainee is able to trouble shoot the created defect early. create another defect and askthe trainee to service that and then other defect and so on.

Procedure

TASK 1:- Identification of components and Tracing the circuit

1. Remove the back cover of the given B&W TV receiver. As demonstrated by your instructor,detach the connectors from the PCB such that the PCB can be pulled out of the cabineteasily for the purpose of circuit tracing. Position the PCB is such that the component side ofthe PCB is facing you. Get it checked by instructor.Keep all screws, nut fateners etc, saftely in a transparent cover, Label all the detachedonnectors/ Wires so that it is easy while reconnecting them back in their place.

2. Referring to the circuit schematic of the horizontal output section, locate the componentshorizontal output section on PCB. Record the identified components symbols in the O&Tsheet (similar to the PCB layout) in the place marked as “Space for rough skotch of thecomponent layout with tracks”.

EXPERIMENT 17 - TROUBLE SHOOTING IN HORIZONTAL OUTPUT STAGE OF A B& WTV RECEIVER

151151151


3. Count the local number of each category of component (like resistor, transistor etc.) Identifiedin horizontal output section and enter in the O&T sheet.

4. Get the rough sketch of traced components of the horizontal out put section cheked by theinstructor.

5. Place a table lamp of around 40W at the back side (Solder side) of the PCB. DON’T keepthe bulb very close to the PCB as this may heat-up the components. DON’T keep the bulbcontinuously ON for more than 10 to 15 minutes to avoid PCB getting heated up.

6. Trace the horizontal sub section by marking the links/and connections between componentsymbols drawn on the O&T sheet at step 2.

7. Referring to the circuit diagram of the horizontal out put section from the lesson or givento you by your instructor rearrange and redraw the traced circuit in the O&T sheet markedas “Space for redrawing the final circuit diagram of the traced circuit”

8. Get the traced circuit checked by your instructor.

TASK 2:- Rectifying the simulated fault in the horizontal out put section of the given faultyTV receiver

1. Switch ON the TV set to confirm the informed complaint. Record both the informed complaintand the identified complaint in the sheet.

2. Record the identified defect. Refer trouble shooting chart for the remedial measures.3. Service the defect. Test the stage for its satisfactory working.

If the complaint is not rectified complaint other than informed exists consult your instructor.4. Record the remedial action taken during, servicing along with the components replaced if

any, in the O&T sheet.5. Get your work checked by your instructor.

TROUBLESHOOTING CHART FOR HORIZONTAL OUTPUT STAGE

Sl.No.

1

Observablesymptom

No. raster

Probabledefect(s)

No EHT

No input at thebaseof Q 502

Causes/reasons

Horizontal outputtransistorQ503 BU505defective.HorizontalteansistorQ502 BD 115defectiveOpen LOT primarywibding.R530 50 Ω openR528-4K7 openC523 -3K9 shorted.Defective horizontaloscillation section

Remedical measures

Check and replace Q503


Check and replace LOT

Check and replace R530Check and replace R528Check and replace C 523Check input to Q 502

152152


EXPERIMENT 18 - TROUBLE SHOOTING IN VERICAL SECTION OF A B & W TV RECEIVER

Objectives

On completion of this exercise you shall be able to• Identify the components/devices of the vertical section and draw their corresponding symbols• Trace the circuit diagram of vertical section of given reference B&W TV• Rearrange the traced circuit in sequence from input to output• Rectify the simulated fault in the vertical section

Requirements

Materials/Components Tools/Equipments/Instruments• B& W TV receiver - 1 No. • Trainees kit –1 No.

CRO 15 MHz with B.N.C. connector – 1 No.

Hints to Instructor

1. The instructor shall make available circuit/ service manual for the B &W TVs models usedin this exercise.

2. Make copies of the circuit diagram of different stages (vertical section for this exercise) forthe trainees to perform this exercise and subsequent exercise. Issue the copies of the circuitonly after the trainee completes the rough tracing.

3. Instead of asking the trainees to open the B&W TV and trace the circuit , if spare boards ofthe same B& W TV is available , the spare boards can be given for tracing practice.

4. Demonstrate the method of pulling out the PCB suitable for tracing.5. The instruction shall simulate certain faults in the vertical section of the T.V. receiver set,

for the trainees to carryout fault finding and servicing . Refer problem tree for simulatingdefects.

6. If the trainees is able to trouble shoot created defect early , create another defect and askthe trainee to service that and then other defect and so on.

Procedure

Task 1 : - Identification of components and tracing the circuit

1. Remove the back cover of the given B&W TV receiver . As demonstrated by you instructor,detach the connectors from the PCB such that the PCB can be pulled out of the cabin easilyfor the purpose of circuit tracing . Position the PCB such that the component side of thePCB is facing you. Get it checked by instructor.Keep all screws, nut, fasteners etc. safely in a transparent cover. Label all the detachedconnectors/wire s so that it is easy while reconnecting them back in their place.

2. Referring to the circuit schematic of the vertical section, locate the components of verticalsection onPCB ,. Record the identified components symbols is the O&T sheet (similar tothe PCB layout ) in the place marked as “Space for rough sketch of the component layoutwith tracks”

3 Count the total number of each category of component (like resistor , transistor etc. )identified in vertical stage and enter in the O&T sheet.

4. Get the traced rough sketch of component of the ertical section checked by the inatructor

153153153


5. Place a table lamp of around 40W at the back side (Solder side) of the PCB.DON’T keepthe bulb very close to the PCB as this may heat-up the components. DON’T keep the bulbcontinuously ON for more than 10 to 15 minutes to avoid PCB getting heated up.

6 Trace the vertical section by marking the links/and connections between component symbolsdrawn on the O&T sheet as step 2

7 Referring to the circuit diagram of the vertical section,( from lessonor given to you by yourinstructor rearrange and redraw the traced circuit in the O&T sheet marked as “ Space forredrawing the final circuit diagram of the traced circuit.”

9 Get the traced circuit checked by your instruction

Task 2 Rectifying the simulated fault in the vertical section of the given faulty TV receiver

1. Switch On the TV not to conform the informed complaint Record both the informed complaintand the identififed complaint in the O &T sheet

2. Record the identified defect. Refer troubleshooting shart for the remedial measures specifiedvoltage levels at different the test points in Table 2 of O&T sheet.

3. Service the defect. Test the stage for its satisfactory workingIf the complaint is not rectified ,complaint other than informed exists consult your instructor.

4 Record the remedial action taken during serviciing along with the components replaced ifany, in the O&T sheet

5 Get your work checked by your instrucor.

154154


TROUBLESHOOTING CHART –1 FOR VERTICAL SECTIONSLNo.

Observablesymptom

AdditionaSynplom

Probabledefect(s)

Causesreasons Remedial

measures

Bright horizo-ntal line only

1 Sound ok Defective verticaloscillation section

Defective verticalout put section

Defective verticaldeflection coil

Less/No powersupply to verticalsection /

Defective transistor BC 147

Defective IC

Open Coil

Defective powerline and seriesresistor and filtercapacitor/

Check and replace thedefective component




Insufficientpicture/rasterheight/

2 Sound okPicture ok

Less voltage atenitter of Q 401V

Voltagesabnormal at Q401

Height controlVR 402 , 470 KDefective R 411, R410 and VR 403

Leaky transistordue to ageing

Check and replaceVR 402, R411 R 410 and Vr 403


3. Picture rolling qvertically

Sound okPicture ok/

Q401 base voltageabnormal VR 401

50 Hz pulses notavailable at the base of Q 401

Check VR 401 andreplace

Check the wiringfrom pin no.7 of CA 920,R401,10k, C401,22kpf,R402k. C401, 22kpfand C403 1uf.

Picturecramping orfold over thebottom

Check and correct thevoltage gain to pin no.10of IC 1044

Check C 703 0.15uf andCheck C705 25uf/25vand replkace

Check the voltages in eachpin if found variationreplace the IC

Check R 707 and R 708open/short and replace bynew one

. Check R704, R705 andR709 and found if

change in value replace them.

Defective holdcontrol.

There may be loosecontact through thewiring from pin no.7of CA 920 to baseof Q401

4 Sound ok Abnormalvoltagefunctuation

Defective leakuy capactor

Defective IC 1044

Defective resistors R707, R to8,R 704 , R705

Low power supply10 IC 1044

Due to long use.

Due to long use.

Due to long use

155155155


EXPERIMENT 19 - TROUBLE SHOOTING IN VIDEO AMPLIFIER STAGE ON A B & W TVRECEIVER

Objectives

On completion of this exercise you shall be able to· Identify the components/devices and draw their corresponding symbols· Trace the circuit diagram of video amplifier section of a B& W TV· Rearrange the traced circuit in sequence from input to out put· Rectify the simulated fault in the video amplifier section

Requirements


• B&W TV receiver –1 No. • Trainees kit

CRO 15 MHz –1 No


1. The instructor shall make available circuit/service manual for the B&W TVs models usedin this exercise.

2. Make copies of the circuit diagram of different stages ( video section for this exercise ) forthe trainees to perform this exercise and subsequent exercise

3. Instead of asking the trainees to open the B&W TV and trace the circuit, if a spare board ofthe same B&W TV is available , the spare boards can be given for tracing practice.

4. Demonstrate the method of pulling out the PCB from the TV and positioning the main PCBsuitable for tracing .

5. The instructor shall simulate certain faults in the video section of the T.V receiver set, forthe trainees to carry out fault finding and servicing . Refer problem tree for simulatingdefects.

6. If the trainee is able to trouble shoot created defect early, create another defect and ask thetrainee to service that and then other defect and so on.

Procedure


1 . Remove the back cover of the given B&W TV receiver.As demonstrated by your instructor,detach the connectors from the PCB such that the PCB can be pulled out of the cabin easilyfor the purpose of circuit tracing . Position the PCB such that the component side of thePCB is facing you. Get it checked by instructor.Keep all screws , nut, fasteners etc. safely in a transparent cover. Label all the detachedconnectors/wire s so that it is easy while reconnecting them back in their place.

2. Referring to the circuit schematic of the video section, locate the components of videosection on PCB ,. Record the identified components symbols is the O&T sheet (similar tothe PCB layout ) in the place marked as “Space for rough sketch of the component layoutwith tracks”

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3. Count the total number of each category of component (like resistor, transistor etc)Identified in video l section and enter in the O&T sheet.

4. Get the traced rough sketch of components of the video section checked by the instruction5. Place a table lamp of around 40w at the back side (solder side) of the PCB. DON’T keep

the bulb very close to the PCB as this may heat-up the components . DON’T keep the bulbcontinuously ON for more than 10 to 15 minutes to avoid PCB getting heated up.

6 Trace the video section by marking the links/and connection between component symbolsdrawn on the O &T sheet at step 2

7 Referring to the circuit diagram of the video section from the lesson or given to you byyour instructor rearrange and redraw the traced circuit in the O&T sheet marked as “Spacefor redrawing the final circuit diagram of the traced circuit”


Task 2. Rectifying the simulated fault in the video section of the given faulty TV receiver

1 Switch On the TV set to confirm informed complaint. . Record both the informed complaintand the identified complaint in the O & T sheet.

2 Record the identified defect. Refer trouble-shooting chart for the remedial measures.3 Service the defect. Test the stage for its satisfactory working

If the complaint not rectified/the complaint other than informed exists. Consult your instructor4 Record the remedial action taken during servicing along with the components replaced if

any, in the O&T sheet5 Get your work checked by your instructor .

157157157


TROUBLESHOOTING CHART –1 FOR VERTICAL SECTION

SL.No.

Observablesymptom

AdditionalSymptom

Probabledefect(s)

Causes reasons

Remedialmeasures

1 No picture Sound ok Defective videoout put transistorBD115/in Operativ/inOperative Videotransistor BD 115

Transistor leakyDue to aging andsurge voltage theresistor may getopen

Test and replaceBD 115. Test andreplace R209

2 Dull picture(poorContrast)

Sound ok Contrast controldefective Mechanical defect

Loose/drysoldered joint

Leaky outputtransistor BD 115(Q201)

Due to frequent andlong use/poorquality

Long use

Due to long use

Replace and test.

Resolder

Replace/test Q201

3. Smeared picture/

Sound ok,Brightnessandcontrastalso ok

Bypass capacitordefective C 206,204

Shorted videocoupling capacitorC202,C203

Poor quality

Poor quality

Test and replace C206C203

Test and replace C202,C 203

4 IntermittentPicture

Sound ok Dry/loose solder atthe video outputstage

Defectivebrightness andcontrast control

Long use

Dirty/ Wornout

Resolder

Test and replace

158158


EXPERIMENT 20 - TROUBLE SHOOTING IN SOUND SECTION OF A B & W TV RECEIVER

Objectives

On completion of this exercise you shall be able to. identify the components/devices and draw their corresponding symbols. trace the circuit diagram of sound section of given reference B&W TV. rearrange the traced circuit in sequence from input to output. rectify the simulated fault in the sound section.

Requirements


• B& W TV receiver - 1 No./batch. Trainees kit

A.M/F.M.signal generator - 1 No.

CRO 15 MHz - 1 No.


1 The instructor shall make available circuit/service manual for the B&W TVs models usedin this exercise.

2 Make copies of the circuit diagram of different stages [sound section for this exercise] forthe trainees to perform this exercise and subsequent exercis.

3 Instead of asking the trainees to open the B&W TV and trace the circuit, if spare board ofthe same B&W TV is available, the spare boards can be given for tracing practice.

4 Demonstrate the method of pulling out the PCB from the TV and positioning the main PCBsuitable for tracing.

5 The instructor shall simulate certain faults in the sound section of the T.V receiver set, forthe trainees to carryout fault finding and servicing. Refer problem tree for simulating defects.

6 The trainess may be given as many as defects one by one depending on the availability oftime.

Procedure

TASK 1:-Identification of components and Tracing the circuit

1 Remove the back cover of the given B&W TV receiver. As demonstrated by yourinstructor,detach the connectors from the PCB such that the PCB can be pukked out of thecabinet easily for the purpose of circuit tracing. Position the PCB such that the componentside of the PCB is facing you. Get it checked by instructor.Keep all screws, nut, fasteners etc. safely in a transparent cover. Label all the detachedconnectors/wires so that it is easy while reconnecting them back in their place.

2 Referring to the circuit schematic of the sound section,given in the lesson or given to youby your instructor locate the components of sound section on PCB. Record the identifiedcomponents symbols in the O&T sheet [similar to the PCB layout] in the place marked as“Space for rough sketch of the component layout with tracks”

3 Count the total number of each category of component [like resistor,transistor etc.] Identifiedin sound section and enter in the O&T sheet.

159159159


4 Get the rough sketch of traced compoments checked by the instructor.5 Place a table lamp of around 40W at the back side [solder side] of the PCB. DON’T keep

the bulb very close to the PCB as this may heat-up the components. DON’T keep the bulbcontinuously on for more than 10 to 15 minutes to avoid PCB getting heated up.

6 Trace the sound section by marking the links/and connections between component symbolsdrawn on the O&T sheet at step 3.

7 Referring to the circuit diagram of the sound section from the lesson or given to you byyour instructor rearrange and redraw the traced circuit in theO&t sheet marked as “Spacefor redrawing the final circuit diagram of the traced circuit”.

8 Get the traced circuit checked by your instructor.

TASK 2:- Rectifying the simulated faults in the sound section of the faulty TV receiver set

1 Swith ON the B&W TV set to confirm the informed complaint. Record both the in formedcomplaint and the identified complaint in the O&T sheet.

2 Record the identified defect. Refer trouble-shooting chart for the remedial measures.3 Service the defect. Test the stage for its satisfactory working.

if the complaint is not rectified/if complaint other than informed exist,consult your instructor.4 Record the remedial action taken during servicing along with the components replaced if

any, in the O&T sheet.5 Get your work checked by your instructor.

160160


Sl. Observable Additional Probable Causes/ RemedialNo. symptom symptom defect[s] reasons measures1 No sound Picture ok Defective Ageing/long use Replace

volume control

Defective speaker Speaker voiceCoilReplace theopen due to speakerlong use.One of the end Re-solder thewires of the end wire orSpeaker dry solderedmay be open

No/low DC supply 220µf or Check andavailable at 100K at pin replace.the pin no.10 shorted/no10 of CA 1190 leaky

Defective IC1190 Short circuited Check and replacein side the IC-abnormal voltageat IC - terminals

Open circuit C301 4.7PF open Check andsound take off reaplace point tosound IF input

2 Weak Picture ok Defective IC Partial short inside Check and replaceSound the IC

Defective Center or hot endvolume control point of V/C may Re-soldered the

get dry soldred jointsor [open]Mechanical Check and replacedisconnection due the new volumeto frequent use control

Defective speaker Cone paper eaten Check and replaceby insects new speaker

3 Hum in Picture ok Low Voltage power Filter capacitor C4,Check and replacesound supply defect 470 µF and C306 , filter capacitor

220 µF leaky dueto long use

Defect in singnal Shielded wire earthCheck and solderline wiring connection drythe shielded earth

soldered connection4 Sound Sound ok Defective volume Dust formation Check and replace disturded control VR 302 inside the volume the volume control

intermittently contorl VR 302 Centre tap contact Check and replaceloosen of VR 302 the volume control

5 Uncontro- Distorted Defecive volume Volume control Re-solder thelled sound sound control CR 302 earth end soldered earth end of VR 302

openVolume control Replace theearth end broken volume controlVR 302

161161161


EXPERIMENT 21 - TROUBLE SHOOTING IN VIF AMPLIFIER OF A B & W TV RECEIVER

Objectives

On completion of this exercise you shall be able to. identity the components/devices of VIF amplifier stage and draw their corresponding

symbols. trace the circuit diagram of VIF section of given reference B&W TV. rearrange the traced circuit in sequence from input to output. rectify the simulated fault in the VIF section.

Requirements


• B&W TV receiver -1 No/batch • Trainee’s kit.

A.M/F.M signal generator -1 No.

C.R.O 15 MHz -1 No.


1 The instructor shall make available circuit/service manual for the B&W TV models used inthis exercise.

2 Make copies of the circuit diagram of different stages [VIF section for this exercise] for thetrainees to perform this exercise and subsequent exercise

3 Instead of asking the trainees to open the B&W TV and trace the circuit, if a spare board ofthe same B&W TV is available, the spare boards can be given for tracing practice.

4 Demonstrate the method of pulling out the PCB from the TV and positioning the main PCBsuitable for tracing.

5 The instructor shall simulate certain faults in the VIF section of the T.V receiver set, for thetrainees to carryout fault finding and servicing. Refer problem tree for simulating defects.

6 The trainees may be given as many as defects one by one depending on the avail ability oftime.

Procedure

TASK 1:-Identification of components and Tracing the circuit

1 Remove the back cover of the given B&W TV receiver. As demonstrated by your insturctor,detach the connectors from the PCB such that the PCB can be pulled out of the cabineteasily for the purpose of circuit tracing. Position the PCB such that the component side ofthe PCB is facing you. Get it checked by instructor.Keep all screws,nut, fasteners etc. safely in a transparent cover. Label all the deachedconnectors/wires so that it is easy while reconnecting them back in their place.

2 Referring to the circuit schematic of the sound section, locate the components of VIFsection on PC. Record the identified components symbols in the O&T sheet [similar to thePCB layout] In the “Space for rough sketch of the component layout with tracks” proved inthe O&T sheet.

3 Count the total number of each category of component[like resistor, transistor etc.] Identijied

162162


in VIF section and enter in the O&T sheet.4 Get the rough sketch of traced components of the VIF sectionchecked by the instructor5 Place a table lamp of around 40W at the back side [solder side] of the PCB. DON’T keep

the buib very close to the PCB as this may heat-up the components. DON’T keep the bulbcontinuously ON for more than 10 to 15 minutes to avoid PCB getting heated up

6 Tracing of VIF section by marking the links/and connections between component symbolsdrawn on the O&T sheet at step 3.

7 Referring to the circuit diagram of the VIF section from lesson or given to you by yourinstructoe rear-range and redraw the traced circuit in the O&T sheet marked as “Space forredrawing the final circuit diagram of the traced circuit”.

8 Get the traced circuit checked by your instructor

TASK 2:- Rectifying the simulated fault in the V.I.F stage of a faulty TV receiver

1 Switch ON the TV set to confirm the informed complaint. Record both the informed complaintand the identified complaint in O&T sheet.

2 Record the identified defect. Refer troubleshooting chart for the remedial measures.3 Service the defect. Test the stage foe its satisfactory working.4 Record the remedial action taken during servicing along with the components replaced if

any, in the O&T sheet.If the complaint is not rectified/if complaint other than informed exists consult your instructor.

5 Get your work checked by your instructor.

TRQUBLESHOOTING CHART -1 FOR VISIOM IF AMPLLIFRE

Sl. Obsevable Additional Probable Causes/ Remaedial measeues No, sympotom sympotom defect(s) reasons1. No picture, Raster Ic shorted Due to long use Check and replice the no sound normal VIF IC 7611

IC pins making Dry soldering Re-soldering the IC pin Loose Contact and check

No low voltage Limiting resisor Check and replace R104 supply R104 gets open C117 leaky Check and replace C117

Excessive AGC AGC VR 301 Check and replace VR 301 damaged

2 Weak Picture Raster Weak IC Due to long use Replace the V.I.F IC 701 poor contrast normal (Note: The voltage in pins may be normal ) AGC insufficient AGC VR 101 Check and correct AGC misposition voltage between -2 to- 4V by adjusting VR 301 for correct contrast

163163163


EXPERIMENT 22 - MOUNTING AND TESTING OF VHF TUNER

Objectives

On completion of this exercise you shall be able to. mount the tuner into a cabinet. test the tuner. rectify the simulated faults in the tuner section.

Requirements


• VHF tuner-turret type with -1 No. • Trainees’kit

• knobes-12 channel • Working B/W TV receiver -1 No.

• Partially assembled kit -1 No. • Multimeter -1 No.

• Yagi antenna-5 element -1 No.

with cable for local TVstation.


1 The instructor shall demonstrate the removing & mounting procedure of turret tuner intothe available cabinet

2 For testing the tuner, a working TV receiver may be used. In this, replace the old tuner withnew tuner. Then testing of tuner may be carried out.

3 The demonstration of mounting and testing of ELECTRONIC TUNER may also be carriedout if available.

Procedure

TASK 1:- Mounting of tuner

1 Mount the turret/electronic tuner into the available cabinet as demonstrated by yourinstructor.

2 Get your work checked by the instructor.

TASK 2:- Connecting and testing of tuner

1 With reference to the circuit diagram. Connect B+, AGC, -ve, input wire connections ofturret/electronic tuner.

2 Get the connections checked by the instructor.3 Connect antenna to the TV receiver.4 Switch ON the receiver, and set the tuner to the local channel,adjust the fine-tuning control

for sharp picture and noise free sound.5 Measure and record the DC voltage at B+, AGC in the O&T sheet.6 Get your work checked by your instructor.

164164


TASK 3:-Rectify the simulated faults in the tuner

1 Switch ON the TV receiver to confirm the informed complaint. Record both the informedcomplaint and the identified complaint in the O&T sheet.

2 Record the identified defect. Refer trouble-ahooting chart for the remedial measures.3 Service the defect. Test the TV tuner for its satisfactory working.

If the complaint is not rectified/if complaint other than informed exists consult your instructor.

TROUBLESHOOTING CHART -1 for Sound section

Sl. Observable Additional Probale Causes/ Remedial measures No. symptom symptom defect[s] reasons 1 No picture Raster No signal input Antenna problem Check antenna co-

no sound with snow to the tuner Antenna cable- nnection check anddefective replaceOpen Balun Check and replace Balun

Defective tuner Check and replace tuner

No voltage R-1KW open. Check and replace available to the C-100uF shorted Check and replace tuner 12V+ve wiring Check and connect

discinnection. -ve supply line out. Check and connect

2 Weak signal Incorrect antenna Check and correct available to the orientation.

tuner Incorrect channel Check and selectselection. correct channel and tuner

Tuner output low Defective tuner Check and replaceLow+ve voltage Check and correct

C and R the supplyvoltage to the tuner

165165165


EXPERIMENT 23 - IDENTIFY DIFFERENT STSGES AND MAIN COMPONENTS OF A CTV

Objectives

On completion of this exercise you shall be able to. identify the different stages of a CTV. identify the different service controls provided on CTV PCB. identify various components in different stages.

Requirements


• CTV receiver - 1 No./batch. • Trainees minium tool kit - 1Set.

• Colour sketch pens -1Set.


1 ASSUMPTION MADE:During the development of this Exercise and for some informaionsgiven in lessons, as a refernce, ITT colour Television Kit [German] has been choosen as itis found to be easy to understand as well quite popular. Hence, for the circuit, componentlayout etc., to the ITT kit is chosen as reference. If the institute is using any other kit such asHitachi, National,Samsung, BELetc., then, the instructor has to carry out suitablemodifications in the exercises. Although, care is taken to make the procedural steps in theexercises quite applicable to whatsoever the kit used for training, certain material that gowith the procedural steps such as,the component layout, circuit diagram need to be modified.Therefore,for those institutes using CTV kits other than the ITT kit they shouldpreparenecessary materias at least one week in advance before conducting this and subsequentexercises and its related lessons.

2 Instructor shall label the main components and service controls [refer table given at the endof this exercise] on the component side of the CTV PCB. The labelling can be A-1 to A-xx,B-1 to B-xx, C-1 to C-xx and so on. The label A-xx shall correspond to to a particularstage[for example: Power supply stage] label B-xx shall correspond to an other stage [forexample: Horizontal section] and so on.

3 Hints given at 1 and 2 above is applicable for all the four different types/kits of CTV to begiven for the trainess for practice.

Procedure

Precaution:In this exercise, since you are opening the CTV and handle the PCB, this exercise shouldbe done with the mains cord removed from mains supply. Hence, DO NOT start this exerciseunless the mains cable to the CTV is removed from the mains supply socket.

1 As demonstated by your instructor, open the back cover of the CTV and pull out the PCBout of the chassis.Place the pulled out PCB on the rubber mat[if the connected wire lengths allow] or make itrest stably on one of the side walls of the CTV cabinet or as suggested by your instructor.

2 Refer Table given at the end of this exercise and locate component/control[Mains supplyinput points,M1-M2] on the pulled out PCB.On locating the component/control you will find, a label number[for example, A-9 or B-7and so on]&-some printed information by the side of the component on the PCB.

166166


3 In the component layout diagram [without the component details marked] given in recordsheet record the label number of the located component.

4 Get the located component checked by your instructor.5 Repeat step 2 and 3 for all the listed components given in table and any other additional

components added to the list by your instructor.6 From the recorded table number of the compoents, in the component layout [in record

sheet], identify the components belonging to a stage. Using colour pencils mark all thecompoents/controls of a perticular stage using one colour as suggested in table.

7 Get the located compoents and coloured stage wise compononts checked by your instructor

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EXPERIMENT 24 - IDENTITY AND TEST NECK COMPONENTS OF A COLOUR-PICTURETUBE

ObjectivesOn completion of this exercise you shall be able to. identify the external parts of a colour picture tube. measure resistance of yoke colls. identity magnets in the neck of the picture tube. check the degaussing operation.

Requirements


• Colour TV receiver -1 No. • Minimum tool kit -1 Set.

• Multimeter -1 No.


1 Do not connect power supply to the colour TV set while doing this exercise.2 Before conducting this exercise label the parts of a colour picture tube for the trainees to

identify. Referlesson 19.04 for the different parts to be labeledPrecaution: Do not disturbthe setting of made at the picture tube neck assembly. Also do not disturb the rubber wedgesused for fixing the deflection yoke.

Procedure

TASK 1:- Name the external parts of a colour picture tube

1 Remove the back cover of the CTVand keep the fitting screws safely.

2 Select a label put on the picture tube.3 Identify the name of the labelled part

and record in Table 1 of O&T sheet.4 Repeat step 2 and 3 for all the other

labels.5 Get the work checked by your

instuctor.

TASK 2:- Identification of picture

tube-neck components

1 Identity deflection yoke and its connection. Note down the colours of wires Refer Fig 1 forhelp.

2 Remove the wire connection to the yoke. Measure resistance across coil terminals[horizontaland vertical coils] of the yoke and record in Table 2.The yoke coil has 4 terminals, 2 for horizontal defection coil and the other two for verticaldeflection.

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3 Fix the connections of deflection yokein original position.

4 Identify the degaussing coil. ReferFig 2 for help.

5 Identify the different magnets and record their name in the Table 3 ofO&T sheet. Refer Fig 1 for help.Get your work checked by yourinstructor.

TASK 3:- Degaussing operation1 Connect a Multimeter/voltmeter

across the degaussing coil connector.Get it checked by instructor.Ensure that the TV is in Off conditionwhile measuring. Set the Multimeterto AC 300/ 500V range or use asuitable range voltmeter

2 Switch ON TV observing Multimeter deflection and theduration for which the deflection existed.

3 Record the observed maximum voltage reading andapproximate duration for the voltage to becomemimimum in Table 4 of O&T sheet.

4 Repeat step 3 by sswitching OFF and ON the TV atleast2 times to confirm recording reading.

5 Get the recored reading checked by your instructor.Close the back cover of the TV.

Colour picture tube specification

1 Control grid 52 Green cathode 63 Screen grid(G2 ) 74 Red cathode 85 Filament 9, 106 Blue cathode 117 No connection 4, 12.

Fig 2

1

2

3

4

5

678

9

10

11

12

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EXPERIMENT 25 - TRACING THE SMPS STAGE OF A GIVEN CTV RECEIVER

ObjectivesOn completion of this exercise you shall be able to· Identify the components/devices and draw their corresponding symbols· Trace the circuit diagram of given SMPS stage of CTV· Rearrange the traced circuit in sequence from input to output· Identify and measure voltage at test point

Requirements


• CTV receiver -no/batch • Trainees tool kit

• Table lap -1No./ batch

• Magnifying glass –1 No. /batch

Hints to Instructor1. The instructor shall make available circuit/ service manual for the colour TVs models used

in this exercise if the circulit of the CTV’s used is different from the ITT kit for whichdetails are given here.

2. Make copies of the circuit diagram of different stages (SMPS stage for this exercise )for thetrainees to perform this exercise and subsequent exercises .Issue the copies of the circuit,only after the trainee completes the rough tracing.

3. Instead of asking the trainees to open the CTV and trace the circuit , if spare boards of thesame CTV is available , the spare boards can be given for tracing practice. And only voltagemeasurement can be done using the integrated working CTV.

4. Demonstrate the method of pulling out the PCB from the TV and positioning the main PCBsuitable for tracing .and voltage measurement practice

Precautions1. Discharge the stray capacitance of the picture tube.2. Keep the TV OFF when performing the tracing task3. While tracing the circuit never bend the component or force the wires.4. If any wire gets cut during the tracing work, immediately inform the instructor and get it

resoldered.Procedure


1. Remove the back cover of the given C TV receiver . As demonstrated by you r instructor,detach the connectors from the PCB such that the PCB can be pulled out of the cabin easilyfor the purpose of circuit tracing. Position the PCB such that the component side of thePCB is facing you. Get it checked by instructor.Keep all screws , nut, fasteners etc. safely in a transparent cover. Label all the detachedconnectors/wire s so that it is easy while reconnecting them back in their place.

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2 Keep ready the circuit diagram of the SMPS stage of the CTV in the pulled –out PCB,referring to the circuit schematic of the SMPS stage given in lesson 24,04. or given you byyour instructor

3. Referring to the circuit schematic of SMPS stage, locate the components of SMPS stage onPCB. Record the identified component symbols in the O&T sheet (similar to the PCB layout)in the “Space for rough sketch of the component layout with tracks provided in the O&Tsheet.

4 Count the total number of each category of component (like resistor , transistor etc. )identified in SMPS stage and enter in the O&T sheet.

5. Get the traced rough sketch of traced components of the SMPS stage checked by instructor.6. Keep an adjustable type table lamp at the back side (soldor side) the PCB

Use table lamp of at least 40w. DON’T keep the bulb very close to the PCB as this mayheat-up the component .DON,T keep the bulb continuously drawn ON for more than 10 to20 minutes to avoid PCB getting heated up.

7 Tracing SMPS stage starting from mains cord, to DC output terminals of SMPS by markingthe links/and connections between component symbols drawn on the record sheet at step 3.

8 Referring to the circuit diagram of the SMPS stage given to you by your instructor ) rearrangeand redraw the traced circuit in the O&T sheet marked as “ Space for redrawing the finalcircuit diagram of the traced circuit.”


Task 2 Identify and measure voltage at test points of SMPS stage of CTV.

1. Referring to the given circuit of the SMPS, mark the location of the test point on the tracedcircuit and on the track side of the PCB using a red colour sketch pen

2. Record the specified voltage levels at different the test points3. In the test points marked on the given circuit diagram , the expected / specified voltage is

also given four your reference while making voltage mesurememt4. Fix the connectors (removed for tracing ) back to the main PCB and get it checked by your

instructor.Keep the PCB outside the cabinet as voltages at test points are to be measured in the nextstep.

5 In the presence of your instructor , switch on the TV and check it is working satisfactory.If not, consult you instructor .Be aware that you are working in a very high voltageenvironment.

6 As demonstrated by your instructor , measure the voltage levels at the test point and recordmeasured values in of O&T sheet.Do not measure voltage at points / placed other than those marked.

7 Get the recorded voltage at the test point checked by your instructor.8. Switch –off CTV and place the PCB back inside the TV cabinet in its original position.

Get it checked by your instructor.9 Close the back cover of the TV and recheck the satisfactory performace of the TV.

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EXPERIMENT 26 - IDENTIFY CONTROLS & SOCKETS OF CTV AND TUNE PROGRAMCHANNELS


• Locate and identify control and sockets on the front & rear panel of the given Colour TV set.• Tune the colour TV receiver program channels for different on-the air TV program .• Adjust controls for good quality picture and sound.• Operate Colour Television using remote control and adjust picture and sound.

Requirements Materials / Components Tools/ Trainees tools kit

• Colour TV receiver with remote -1 Set /batch Trainees tool kit -1 set • RF cable (direct probe) - 1 No./batch

Hints to Instructor1. Minimum of four Colour TV sets of different makes need to be used for the exercise. A

batch of 4 trainees shall work on each CTV at a time.2. Demonstrate the function of controls & sockets found on he front & rear panel of CTVs.3. Demonstrate the procedure for tuning the CTV for receiving the local TV program.4. All the controls & sockets of the CTV given to trainees should be labeled (A,B,C,…..

or 1,2,3,… )before conducting.5. Instructor should give Xerox copies of the relevant operating manual of the CTV and

the remote control. Instructor should demonstrate the use of control on the remote unitbefore the trainee s practice task 2 of this exercise.

Procedure

Task 1 : - Identify controls & sockets on the front and rear panels of CTV.

1- Identify & record the name and function of the labelled controls & sockets available at thefront & rear panel of the given CTV in Table 1 of O&T sheet.Refer given CTV operating manual if necessary.

2. Get the identified parts & functions checked by your instructor.3. Connect antenna to the RF input of the CT.V. Switch On main supply to CTV and adjust the

brightness . Contrast, Sharpness ,Colour & Volume controls to the mid position.This ensures sure visibility of picture and audibility of sound while tuning the CTV toprograms.

4. As demonstrated by your instructor tune the program selector-1 of the CTV to any of theavailable on-the-air program (local TV channel as demonstrated by your instructor.

5. Re –adjust the brightness, Contrast, Sharpness ,Colour & Volume controls such that thepicture and audio is clear and sharp. Record the received program channel(viz ,DD Sportsin the table 2 of O&T sheet.

6 Get the tuned program and the set controls checked by your instructor.

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7 Repeate steps 4 and 5 to tune Program selectors .2 to 6 on the CTV to different programs.8 Get your work checked by your instructor. Return the given CTV and obtain another

CTV of new type /make/modelOn completion of this step, instructor will give you a different make of CTV in which thecontrols and sockets on the front & rear panels my be different.

9. Repeat steps 1 to 7 for the newly given CTV.10. Repeat steps 8 and 9 till you have practiced this task for at least four different type of

CTV’s.

TASK 2 :-Identify the different controls/ functions available on the remote control unit of a

Colour TV set.

1 Refer the given remote control unit manual and identify the location and functions ofdifferent control buttons on the given remote control unit. Record the symbol of the buttonson the remote (rough sketfch only) and their functions in the space provided in O&T sheetand Table 3.

2. Operate different controls of TV through the remote contorl unit and set Colour, brightness,contrast and sound to required level for all the programs to which the CTV was turned atTask 1.

3. Get your work checked by instructor.4. Very the distance & angle between the remote control and the TV and find the approximate

maximum distance and angle within which the remote control works effectively. Recordthe distance and the angle in the O&T sheet.

5. Get your work checked by instructor .6. Switch OFF the CTV and remove antenna connection

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EXPERIMENT 27 - IDENTILY TUNER TERMINALS AND REPLACE TUNERS


• identify Tuner terminals• measure voltages at terminals• replace tuner.

Requirements


• Colour TV receiver -1 No. / batch • Trainees tool kit - 1 Set.

• Tuner - 1 No. / batch. • Multimeter -1 No.

Procedure

Task 1:- Identify tuner and measure voltage at tuner terminals

1. Remove the back cover of the CTV receiver, and position the PCB such that the solderside of the PCB faces you as demonstrated by your instructor.Keep all screws, nut, fasteners etc. safely in a transparent cover.Label the detached connectors for easy identification

2. Identify the tuner and is terminals referring the Fig and record the Terminals pin names /identification marks on Table 1 of the Record sheet.

3. Mark the test points on the track side of the PCB with a sketch pen referring to the givencircuit.

4. Get the marked test points checked by your instructor.5. Record the specified voltage for the test points in Table 1 of record sheet.6. Switch - on the Television.7. Measure the voltage on the marked terminals of the tuner and record the same in Table 1

of the record sheet.8. Switch off the Television.9. Get the work checked by your instructor.

Task 2 : - Removing and re-fixing tuner

In the reference ITT circuit provided the RF, IF, AF modules are arranged in a separateboard which is soldered to the main PCB. In other type of circuits / models brands the Tunercomes as a separate unit in a box which is soldered to the Main PCB and all other stages areaccommodated in the main PCB. In such cases the tuner can be replaced easily...

1. De-Solder the tuner terminals.

2. Detach the tuner form the PCB as demostrated by your instructor.

3. Re-fix a tuner on the PCB.

Before replacing a new tuner verify the terminals for compatibility with the old/new tunerwhich is removed. In case of non compatibility, manually wire the tuner terminals.

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4. Solder the tuner terminals.

5. Get the work checked by your instructor.

6. Switch-on the Television, tune the Television for available channels.


8. Close the back cover of TV.

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EXPERIMENT 28 - TRACING OF VIDEO IF AMPLIFIER SECTIONObjectives

On completion of this exercise you shall be able to

• Identity the components / devices and draw their corresponding symbols

• trace the circuit diagram of video IF amplifier section of CTV

• rearrange the traced circuit in sequence form input to output

• Identify and measure voltage at test points.

Requirements


• C T V receiver - 1 No./Batch. • Trainees tool kit

• Table lamp -1 No. batch. • Magnifying glass -1 No. batch

Hints to Instructor :

1. The instructor shall make available cirucit/service manual for the Colour TVs models usedin this exercise .

2. Make copies of the circuit diagram of different stages. (Video amplifier stage for this exercise)for the trainees to perform this exercise and subsequent exercises. Issue the copies of thecircuits only after the trainee completes the rough tracing.

3. Instead of asking the trainees to open the CTV and trace the circuit, if spare boards on thesame CTV is available, the spare boards can be given for tracing practive and only voltagemeasurement can be done using the integrated working CTV.

4. Demonstr the method of pulling out the PCB from the TV and positioning the main PCBsuitable for tracing and voltage measurement practice.

Precautions

1. Discharge the stray capacitance of picture tube.2. Keep the TV OFF when performing the tracing task.3. While tracing the circuit never bend the component of force the wires.4. If any wire gets cut during the tracing work, immediately inform the instructor and get it

resoldered.

Procedure

Task 1:- Identification of components and Tracing the circuit

1. Remove the back cover of the given CTV receiver. As demonstrated by your insstructor,detach the connectors from the PCB such that the PCB can be pulled out of the cabineteasily for the purpose of circuit tracing. Position the PCB such that the component side ofthe PCB is facing you. Get it checked by instructor.Keep all screws, nut, fasteners etc. safely in a transparent cover. Label all the detachedconnectors/ wires so that it is easy while reconnecting them back in their place.

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2. Keep ready the circuit diagram of the video IF stage of the CTV. In the pulled-out PCB,referring to the circuit schematic of the video IF stage given.

3. Referring to the circuit schematic of the video IF stage, locate the components of Video IFstage on PCB. Record the identified component symbols in the O&T sheet (similar to thePCB layout) in the “Space for rough sketch of the component layout with tracks providedin the O&T sheet.

4. Count the total number of each category of component (like resistor, transistor ertc,)indentified in video IF stage and enter in the O&T sheet.

5. Get the traced rough shetch of traced components of the video IF stage checked by instructor.6. Keep an adjustable type lable lamp at the back side (solder side) of the PCB.

Use a table lamp of atleast 40w, DON’T keep the bulb very close to the PCB as this mayheat-up the components. DON’T keep the bulb continuoualy ON for more than 10 to 15minutes to avoid PCB getting heated up.

7. Tracing of video IF stage starting form input to output terminals of video IF by marking thelinks/ and connections between component symbols drawn on the record sheet at step 3.

8, Referring to the circuit diagram of the video IF stage by your instructor rearrange andredraw the trced circuit in the O & T sheet marked as “Space for redrawing the final circuitdiagram of the traced circuit”.

9. Get the traced circuit checked by your instructor

TASK2 :-Identify and measure voltage at test points of video IF stage of CTV

1. Referring the given circuit of the video IF, mark the locations of the test points on the tracedcircuit and on the track side of the PCB using a red colour sketch pen.

2. Record the specified voltage level at different test points in Table 2 of O&T sheet.3. In the test points marked on the given circuit diagram, the expected/specified voltage is

also given for your reference while making voltage mesurement.4. Fix the connectors (removed for tracing) back to the main PCB and get it checked by your

instructor.Keep the PCB outside the cabinet as voltage at test points are to be measured in the nextstep.

5. In the presence of your instructor, switch on the TV and check it is working satisfacotirily.If not, consult your instructor.Be aware that you are working in a very high voltage environment.

6. As demonstrated by your instructor, meausre the voltage levels at the testpoints and recordmeasured values in Table 2 of O&T sheet.

7. Get the recorded voltage at the test points checked by your instructor,.8. Switch-off CTV and place the PCB back inside the TV cabinet in its original position. Get it

checked by your instructor.9. Close the back cover of the TV and recheck the satisfactory performance of the CTV.

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EXPERIMENT 29 - TRACING SOUND SECTION OF A COLOUR TV RECEIVER Objectives


• Identity the components / devices and draw their corresponding symbols

• trace the circuit diagram of video IF amplifier section of CTV

• rearrange the traced circuit in sequence form input to output

• Identify and measure voltage at test points.

Requirements


• C T V receiver - 1 No./Batch • Trainees tool kit -1 Set.

• Table lamp -1 No./ batch. • Magnifying glass -1 No./ batch


1. The instructor shall make available cirucit/service manual for the Colour TVs models usedin this exercise .

2. Make copies of the circuit diagram of different stages. (Video amplifier stage for this exercise)for the trainees to perform this exercise and subsequent exercises. Issue the copies of thecircuits only after the trainee completes the rough tracing.

3. Instead of asking the trainees to open the CTV and trace the circuit, if spare boards on thesame CTV is available, the spare boards can be given for tracing practice and only voltagemeasurement can be done using the integrated working CTV.

4. Demonstrate the method of pulling out the PCB from the TV and positioning the main PCBsuitable for tracing and voltage measurement practice.

Precautions:

1. Discharge the stray capacitance of picture tube.2. Keep the TV OFF when performing the tracing task.3. While tracing the circuit never bend the compediately inform the instructor and get it

resoldered.

Procedure

Task 1:- Identification of components and Tracing the circuit

1. remove the back cover of the given CTV receiver. As demonstrated by your instructor,detach the connectors form the PCB such that the PCB can be pulled out of the cabineteasily for the purpose of circuit tracing. Position the PCB such that the component sideof the PCB is facing you. Get it checked by instructor.Keep all screws, nut, fasteners etc. safely in a transparent cover. Lable all the detachedconnectors/ wires so that it is easy while reconnecting them back in their place.

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2. Keep ready the circuit diagram of the Sound stage of the CTV. In the pulled-out PCB,referrring to the circuit schematic of the Sound stage given to you by your instructor.

3. Refferrring to the circuit schematic of the Sound stage, locate the components of soundstage on PCB. Record the identified component symbols in the O&T sheet (similar to 52 thePCB layout) in the “Space for rough sketch of the component layout with tracks” providedin the O&T sheet.

4. Count the total number of each category of component (like resistor, transistor etc,) identifiedin sound stage and enter in the O&T sheet.

5. Get the traced rough sketch of traced components of the Sound stage cheked by instructor.6. Keep an adjustable type lamp at the back side (solder side) of the PCB.

Use table lamp of atleast 40w DONT keep the bulb very close to the PCB as this may heat-up the components. DONT keep the bulb continuously ON for more than 10 to 15 minutesto avoid PCB getting heated up.

7. Tracing of Sound stage starting form input terminals of Sound by marking the links/andconnections between component symbols drawn on the record sheet at step 3.

8. Referring tothe circuit diagram of the Sound stage (given to you by your instructor),rearrange and redraw the traced circuit in the O & T sheet marked as “Space for redrawingthe final circuit diagram of the traced circuit”.


TASK 2 :- Identify and measure voltage at test points of Sound stage of CTV1. Referring to the given circuit of the Sound, mark the locations of the test points on the

traced circuit and on the track side of the PCB using a red colour sketch pen.2. Record the specified voltage levels at different test points in Table 2 of O & T sheet.

In the test points marked on the given circuit diagram, the expected/specified voltage isalso given for your reference while making voltage mesurement.

3. Fix the connectors (removed for tracing) back to the main PCB and get it checked by yourinstructor.Keep the PCB outside the cabinet as voltages at test points are to be measured in the nextstep.

4. In the presence of your instructor, switch on the TV and check it is working satisfactorily,If not, consult your instructor.Be aware that you are working in a very high voltage environment.

5. As demostrated by your instructor, measure the voltage levels at the test points and recordmeasured values in Table 2 of O&T sheet.Do not measure voltage at points/placed other than those marked.

6. Get the recorded voltage at the test points checked by your instructor.7. Switch -off CTV and place the PCB back inside the TV cabinet in its orginal position.

Get it checked by your instructor.8. Close the back cover of the T V and recheck the satisfactory performance of the CTV.

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EXPERIMENT 29 - TRACING SYNC SEPARATOR, AFC AND HORZONTAL OSCILLATOR

Objectives

On completion of this exercise you shall be able to• Identity the components / devices and draw their corresponding symbols• trace the circuit diagram of video IF amplifier section of CTV• rearrange the traced circuit in sequence form input to output• Identify and measure voltage at test points. Requirements


• C T V receiver - 1 No./Batch. • Trainees tool kit -1 Set.

• Table lamp -1 No. batch. • Magnifying glass-1 No. batch


1. The instructor shall make available circuit/service manual for the Colour TVs models usedin this exercise.

2. Make copies of the circuit diagram of different stages (Horizontal oscillator stage for thisexercise) for the trainees to perform this exercise and subsequent exercises. Issue the copiesof the circuits only after the trainee completes the rough tracing.

3. Instead of asking the trainees to open the CTV and trace the circuit, if spare boards of thesame CTV is available, the spare borads can be given for tracing practive and only voltagemeasurement can be done using the integrated working CTV.

4. Demonstrate the mathod of pullining out the PCB from the TV and positioning the mainPCB suitable for tracing and voltage measurment practice.

Precautions:1. Discharge the stray capacitance of picture tube.2. Keep the TV OFF when performing the tracing task.3. While tracing the circuit never bend the component or force the wires.4. If any wire gets cut during the tracing work, immediately inform the instructor and get it

resoldered.PROCEDURETASK 1: Identification of components and Tracing the circuit1. Remove the back cover of the given CTV receiver. As demonstrated by your instructor,

detach the connectors form the PCB such that the PCB can be pulled out of the cabineteasily for the purpose of circuit tracing. Position the PCB such that the component side ofthe PCB is facing you. Get it chaecked by instructor.Keep all screws, nut, fasteners etc. safely in a transparent cover. Label all the detachedconnectors/ wires so that it is easy while reconnecting them back in their place.

2. Keep ready the circuit diagram of the Sync separator, AFC and horizontal oscillator stageof the CTV. In the pulled-out PCB, referring to the circuit schematic of the Sync separator,AFC and horizontal oscillator stage given to you by your instructor.

3. Referrring to the circuit schematic of the Horizontal oscillator stage, locate the componentsof Horizontal oscillator stage on PCB. Record the identified component symbols in theO&T sheet (similar to the PCB layout) in the “space for rough sketch of the component

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layout with tracks” provided in the O&T sheet.4. Count the total number of each category of component (like resistor, transistor etc,) identified

in Honrizontal oscillator stage and enter in the O&T sheet.5. Get the traced rough sketch of traced components of the Horizontal oscillator stage checked

by instructor.6. Keep an adujstable type lamp at the back side (solder side) of the PCB.

Use table lamp of atlseast 40w, DON’T keep the bulb very close to the PCB as this mayheat-up the components. DON’T keep the bulb continuously ON for more than 10 to 15minutes to avoid PCB getting heated up.

7. Tracing of Horizontal oscillator stage starting from input to output terminals of Horizontaloscillator by marking the links/and connections between component symbols drawn on therecord sheet at step 3.

8. Referring to the circuit diagram of the Horizontal oscillator stage (given to you by yourinstructor), rearrange and redraw the traced circuit in the O&T sheet marked as “Space forredrawing the final circuit diagram of the traced circuit”.


TASK 2 :- Identify and measure voltage at test points of Horizontal osscillator stage of

CTV

1. Referring to the given circuit of the Horzontal oscillator, mark the locations of the testpoints on the traced circuit and on the track side of the PCB using a red colour sketch pen.

2. Record the specified voltage levels at different the test points in Table 2 of O&T sheet.3. In the test points marked on the given circuit diagram, the expected /specified volage is

also given for your reference while making voltage mesurement.4 Fix the connectors (removed for tracing back to the main PCB and get it checked by your


5 In the presence of your instructor, on the TV and check it is working satisfactorily. If not ,consult your instructor.

6 As demonstrated by your instrucor,measure the voltage levels at the test points and recordmeasured values.

7 Get the recorded voltage at the test points checked by your inistructor.8 Switch-of CTV and place the PCB back inside the TV cabinet in its origional position.Get it

checked by your instructor.9 Close the back cover of the TV and recheck the satisfactory performance of the CTV.

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EXPERIMENT 30 - TRACING SYNC SEPARATOR, AFC AND HORIZONTAL OSCILLATOR

Objectives

On completion of this exercise you shall be able to• Identity the components / devices and draw their corresponding symbols• trace the circuit diagram of video IF amplifier section of CTV• rearrange the traced circuit in sequence form input to output• Identify and measure voltage at test points.



• Table lamp -1 No. batch. • Magnifying glass-1 No. batch


1. The instructor shall make available circuit/service manual for the Colour TVs models usedin this exercise.

2. Make copies of the circuit diagram of different stages (Horizontal oscillator stage for thisexercise) for the trainees to perform this exercise and subsequent exercises. Issue the copiesof the circuits only after the trainee completes the rough tracing.



Precautions:

1. Discharge the stray capacitance of picture tube.2. Keep the TV OFF when performing the tracing task.3. While tracing the circuit never bend the component or force the wires.4. If any wire gets cut during the tracing work, immediately inform the instructor and get it

resoldered.

Procedure

TASK 1: Identification of components and Tracing the circuit

1. Remove the back cover of the given CTV receiver. As demonstrated by your instructor,detach the connectors form the PCB such that the PCB can be pulled out of the cabineteasily for the purpose of circuit tracing. Position the PCB such that the component side ofthe PCB is facing you. Get it chaecked by instructor.Keep all screws, nut, fasteners etc. safely in a transparent cover. Label all the detachedconnectors/ wires so that it is easy while reconnecting them back in their place.

2. Keep ready the circuit diagram of the Sync separator, AFC and horizontal oscillator stageof the CTV. In the pulled-out PCB, referring to the circuit schematic of the Sync separator,AFC and horizontal oscillator stage given to you by your instructor.

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3. Referrring to the circuit schematic of the Horizontal oscillator stage, locate the componentsof Horizontal oscillator stage on PCB. Record the identified component symbols in theO&T sheet (similar to the PCB layout) in the “space for rough sketch of the componentlayout with tracks” provided in the O&T sheet.

4. Count the total number of each category of component (like resistor, transistor etc,) identifiedin Honrizontal oscillator stage and enter in the O&T sheet.

5. Get the traced rough sketch of traced components of the Horizontal oscillator stagechecked by instructor.

6. Keep an adujstable type lamp at the back side (solder side) of the PCB.Use table lamp of atlseast 40w, DON’T keep the bulb very close to the PCB as this mayheat-up the components. DON’T keep the bulb continuously ON for more than 10 to 15minutes to avoid PCB getting heated up.

7. Tracing of Horizontal oscillator stage starting from input to output terminals of Horizontaloscillator by marking the links/and connections between component symbols drawn on therecord sheet at step 3.

8. Referring to the circuit diagram of the Horizontal oscillator stage ( given to you by youriinstructor), rearrange and redraw the traced circuit in the O&T sheet marked as ”Space forredrawing the final circuit diagram of the traced circuit”.


TASK 2 :- Identify and measure voltage at test points of Horizontal osscillator stage of

CTV

1. Referring to the given circuit of the Horzontal oscillator, mark the locations of the testpoints on the traced circuit and on the track side of the PCB using a red colour sketch pen.

2. Record the specified voltage levels at different the test points in Table 2 of O&T sheet.3. In the test points marked on the given circuit diagram, the expected /specified volage is

also given for your reference while making voltage mesurement.4 Fix the connectors (removed for tracing back to the main PCB and get it checked by your


5 In the presence of your instructor, on the TV and check it is working satisfactorily. If not,consult your instructor.

6 As demonstrated by your instrucor,measure the voltage levels at the test points and recordmeasured values.

7 Get the recorded voltage at the test points checked by your inistructor.8 Switch-of CTV and place the PCB back inside the TV cabinet in its origional position.Get it

checked by your instructor.9 Close the back cover of the TV and recheck the satisfactory performance of the CTV.

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EXPERIMENT 31 - TRACING HORIZONTAL OUTPUT SECTION

ObjectivesOn completion of this exercise you shall be able to• Identity the components / devices and draw their corresponding symbols• trace the circuit diagram of given section of CTV• rearrange the traced circuit in sequence form input to output• Identify and measure voltage at test points.



• Table lamp -1 No. /batch. • Magnifying glass -1 No./ batch.


1. The instructor shall make available circuit /service manual for the Colour TVs models usedin this exercise. .

2. Make copies of the circuit diagram of different stages (Horzontal output stage for thisexercise) for the trainees to perform this exercise and subsequent exercises. Issue the copiesof the circuits only after the traineec completes the rough tracing.



Precautions:1. Descharge the stray capacitance of picture tube.2. Keep the TV OFF when performing the tracing task.3. While tracing the circuit never bend the component or force the wires.4. If any wire gets cut during the tracing work, immediately inform the instructor and get it

resoldered.

Procedure

TASK :- Identification of components and Tracing the circult1. Romove the back cover of the given CTV receiver. As demonstrated by your instructor,

deatch the connectors form the PCB such that the PCB can be pulled out of the cabineteasily for the purpose of circuit tracing.Possition the PCB such that the component side ofthe PCB is facing you. Get it checked by instructor.Keep all screws, nut, fasteners etc. safely in a transparent cover. Label all the detachedconnectors/ wires so that it is easy while reconnecting them back in their place.

2. Keep ready the circuit diagram of the Horizontal output stage of the CTV. In the pulled-outPCB, referring to the circuit schematic of the Horizontal output stage given to you by yourinstructor.

3. Referring to the circuit schematic of the Horizontal output stage, locate the comonents ofHorizontal outpyut stage on PCB. Record the identified component symbol in the O&T

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sheet (similar the PCB layout) in the “Space for rough sketch of the component layoutwith tracks” provided in the O & T sheet.

4. Count the total number of each category of component (like resistor, transistor etc.) identifiedin Horizontal output stage and enter in the O & T sheet.

5. Get the traced rough sketch of traced components of the Horizontal output stage checkedby instructor.

6. Keep an adjustable type table lamp at the back side (solder side) of the PCB.Use a table lamp of atleast 40W DON’T keep the bulb very close to the PCB as this mayheat-up the components.DON’T keep the bulb continuosly ON for more than 10 to 15minutes to avoid PCB getting heated up.

7. Tracning of Horizontal output stage starting from input to output terminals of Horizonaloutput by marking the links / and connections between component sybols drawn on therecord sheet at step 3.

8. Referring to the circuit diagram of the Horizonal output stage (given to you by youinstructor), rearrange and redraw the traced circuit in the O&T sheet marked as “Space forredrawing the final circuit diagram of the traced circuit”.


TASK 2: - Indentify and measure voltage at test points of Horzional output stage of CTV

1. Referring to the given circuit of the Horizontal output, mark the locations of the test pointson the traced circuit and on the track side of the PCB using a red colour sketch pen.

2. Record the specified voltage level at different test points in Table 2 of O&T sheet.In the test points marked on the given circuit diagram, the expected /specified voltage isalso given for your reference while making voltage mesurement.

4. Fix the connectors (removed for tracing) back to the main PCB and get it checked by yourinstructor.Keep the PCB outside the cabinet as voltages at test points are to be measured in the nextstep.

5. In the presence of your instructor, switch on the TV and check it is working satisfacotirily.If not, consult your instrucor.Beaware that you are working in a very high voltage environment.

6. As demonstrated by your instructor, measure the voltage levels at the test points and recordmeasrued values in Table 2 of O&T sheet.Do not measure voltage at points/placed other than those marked.

7. Get the recorded voltage at the test points checked by your instructor8. Switch -off CTV and place the PCB back inside the TV cabinet in its origional position.

Get it checked by your instructor.9. Close the back cover of the TV and recheck the satisfactory performance of the CTV

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EXPERIMENT 32 - TRACING VERTICAL SWEEP SECTION OF A COLOUR TV RECEIVER

Objectives

On completion of this exercise you shall be able to• Identity the components / devices and draw their corresponding symbols• Trace the circuit diagram of given section of CTV• Rearrange the traced circuit in sequence form input to output



• Table lamp -1 No. batch. • Magnifying glass -1 No. batch.


1. The instructor shall make available circuit /service manual for the Colour TVs models usedin this exercise

2. Make copies of the circuit diagram of different stages for the trainess to perform thisexercise and subsequent exerxcises. Issue the copies of the circuits only after thetrainees,completes the rough tracing.

3. Instead of asking the trainees to open the CTV and trace the circuit, if space boards of thesame CTV is available, the spare borads can be given for tracing practive and only voltagemeasurement can be done using the integrated working CTV.


Precautions:

1. Descharge the stray capacitance of picture tube.2. Keep the TV OFF when performing the tracing task.3. While tracing the circuit never bend the component or force the wires.4. If any wire gets cut during the tracing work, immediately inform the instructor and get it

resoldered.

Procedure

TASK 1 :- Identification of components and Tracing the circult

1. Romove the back cover of the given CTV receiver. As demonstrated by your instructor,deatch the connectors form the PCB such that the PCB can be pulled out of the cabineteasly for the purpose of circuit tracing.Possition the PCB such that the component side ofthe PCB is facing you. Get it checked by instructor.Keep all screws, nut, fasteners etc. safely in a transparent cover. Label all the detachedconnectors/ wires so that it is easy while reconnecting them back in their place.

2. Keep ready the circuit diagram of the Vertical Sweep stage of the CTV. In the pulled- outPCB, referring to the circuit schematic of the Vertical Sweep stage given to you by yourinstructor.

3. Referring to the circuit schematic of the Vertical Sweep stage, locate the comonents ofVertical Sweep stage on PCB. Record the identified component symbol in the O&T sheet

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(similar to the PCB layout) in the “Space for rough sketch of the component layout withtracks” provided in the O & T sheet.

4. Count the total number of each category of component (like resistor, transistor etc.) identifiedin Vertical Sweep stage and enter in the O & T sheet.

5. Get the traced rough sketch of traced components of the Vertical Sweep stage checked byinstruction.

6 Keep an adjustable type table lamp at the back side (solder side) of the PCB.Use a table lamp of atleast 40W. DON’T keep the bulb very close to the PCB as this mayheat-up the compoonents. DON’T keep the bulb continuously ON for more than 10 to 15minutes to avoid PCB getting heated up.

7. Tracing to Vertical Sweep stage starting from input to output terminals of Vertical Sweepby marking the likns/and connections between component symbols drawn on those recordsheet at step 3.

8. Referring to the circuit diagram of the Vertical Sweep stage rearrange and redraw thetraced circuit in the O&T sheet marked a s”Space for redrawing the final circuit diagram ofthe traced circuit”.


TASK 2 :- Identify and measure voltage at test points of Vertical Sweep stage of CTV

1. Referring to the given circuit of the Vertical Sweep , mark the locations of the test points onthe traced circuit and on the track side of the PCB using a red colour sketch pen.

2. Record the specified voltage levels at different the test points in Table 2 of O&T sheet.3 In the test points marked on to the given circuit diagra , the expected /specified voltage

mesurement.4 Fix the connectors (removed for tracing) back to the main PCB and get it checked by your


5 In the presence of your instructor, on the TV and check it is working satisfacotirily.If not,consult your instructor.Be aware that you are working in a very high voltage environment.

6 As demonstrated by your instructor, meaisure the voltage level of the test point and recordthe measured values in Table 2 of O & T sheet.Do not measure voltage at points/placed other than those marked.

7. Get the recorded voltage at the points/placed other than those marked.8. Switch -off CTV and place at the PCB back inside the TV cabinet in its origional position.

Get it checked by your instructor.9. Close the back cover of the TV and recheck the satisfactory performance of the CTV

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EXPERIMENT 33 - TRACING OR CHROMA SECTION OF CTV

Objectives

On completion of this exercise you shall be able to• Identify the components/devices and draw their corresponding symbols• Trace the circuit diagram of given chroma section of CTV• Rearrange the traced circuit in sequence from input to out put• Identify and measure voltage at test points


• CTV receiver - 1 No./batch • Trainees tool kit 1 set

• Table lamp - 1 No./batch • Magnifying glass 1 No. /batch


1. The instructor shall make available circuit/service manual for C TVs models used in thisexercise .

2. Make copies of the circuit diagram of different stages (Chroma stage for this exercise ) forthe trainees to perform this exercise and subsequent .Issue the copies of the circuits onlyafter the trainee completes the tracing.

3 Instead of asking the trainees to open the C TV and trace the circuit, if spare board of thesame C TV is available , the spare boards can be given for tracing practive and only voltagemeasurement can be done using the integrated working CTV

4 Demonstrate the method of pulling out the PCB from the TV and positioning the main PCBsuitable for tracing .

Precautions.

1. Discharge the stray capacitance in the picture.2. Keep the TV OFF when performing the tracing task.3. While tracing the circuit never bend the component or force the wire.4. If any wire gets cut during the tracing work, immediately inform the instructor and get

resoldered.

Procedure


1. Remove the back cover of the given C TV receiver. As demonstrated by your instructor,detach the connectors from the PCB such that the PCB can be pulled out of the cabin easilyPCB is facing you. Get it checked by instructor.Keep all screws , nut, fasteners etc. safely in a transparent cover. Label all the detachedconnectors/wire s so that it is easy while reconnecting them back in their place.

2 Keep ready the circuit diagram of the Chroma stage of the CTV . In the pulled out PCB,referring to the circuit schematic of the Chroma stage given to you by your instructor.

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3. Referring to the circuit schematic of the Chroma stage, locate the components of Chromastage on PCB. Record the identified component symbols in the )&T sheet (similar to thePCB layout ) in the “Space for rough sketch of the component layout with tracks providedin the O&T sheet.

4 Count the total number of each category of component (like resistor, transistor etc.) identifiedin Chroma stage and enter in the O&T sheet.

5. Get the traced rough sketch of traced components of the Chroma stage checked by instructor6. Keep an adjustable type table lamp at the back side (soldor side) the PCB

Use table lamp off at least 49 w. Don’t keep the bulb very close to the PCB as this mayheat-up the component .DON,T keep the bulb continuously drawn ON for more than 10 to15 minutes to avoid PCB getting heated up.

7 Tracing Chroma stage starting from input to output terminals of Chroma by marking thelinks/and connections between component symbols drawn on the record sheet at step 3.

8 Referring tp the circuit diagram of the Chroma stage rearrange and redraw the tracedcircuit in the O&T sheet marked as “Space for redrawing the final circuit diagram of thetraced circuit.”


Task 2 Identify and measure voltage at test points of Chroma stage of CTV.

1. Referring to the given circuit of the Chroma , make the location of the test point on thetraced circuit and on the track side of the PCB using a red colour sketch pen

2. Record the specified voltage levels at different test points in Table 2 of O&T sheet.3. In the test points marked on the given circuit diagram , the expected / specified voltage is

also given four your reference while making voltage mesurememt.4. Fix the connectors (removed for tracing ) back to the main PCB and get it checked by your


5 In the presence of your instructor, switch on the TV and check it is working satisfactorily.If not, consult you instructor .Be aware that you are working in a very high voltage environment.

6. As demonstrated by your instructor , measure the voltage levels at the test point and recordmeasured values in Table 2 of O&T sheet.Do not measure voltage at points / placed other than those marked.

7. Get the recorded voltage at the test point checked by your instructor.8. Switch –off CTV and place the PCB back inside the TV cabinet in its original position. Get

it checked by your instructor.9. Close the back cover of the TV and recheck the satisfactory performace of the TV.

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EXPERIMENT 33 - TRACING OF VIDEO OUT PUT SECTION

Objectives

On completion of this exercise you shall be able to• Identify the components/devices and draw their corresponding symbols• Trace the circuit diagram of video output stage of CTV• Rearrange the traced circuit in sequence from input to out put• Identify and measure voltage at test points


• CTV receiver 1 No./batch • Trainees tool kit 1 set

• Table lamp 1 No./ batch • Magnifying glass 1 No. /batch


1. The instructor shall make available circuit/service manual for the Colour TVs models used in lab

2. Make copies of the circuit diagram of different stages (video output stage for this exercise)for the trainees to perform this exercise and subsequent .Issue the copies of the circuits onlyafter the trainee completes the tracing.

3 Instead of asking the trainees to open the C TV and trace the circuit, if spare board of thesame C TV is available , the spare boards can be given for tracing practice and only voltagemeasurement can be done using the integrated work the CTV

4 Demonstrate the method of pulling out the PCB from the TV and positioning the main PCBsuitable for tracing .and voltage measurement

Precautions

1. Discharge the stray capacitance in the picture.tube2. Keep the TV OFF when performing the tracing task.3. While tracing the circuit never bend the component or force the wire.4. If any wire gets cut during the tracing work, immediately inform the instructor and get

resoldered.

Procedure


1. Remove the back cover of the given C TV receiver. As demonstrated by your instructor ,detach the connectors from the PCB such that the PCB can be pulled out of the cabin easilyfor the purpose of circuit tracing . Position the PCB such that the component side of thePCB is facing you. Get it checked by instructor.Keep all screws , nut, fasteners etc. safely in a transparent cover. Label all the detachedconnectors/wires so that it is easy while reconnecting them back in their place.

2 Keep ready the circuit diagram of the video output

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3. Referring to the circuit schematic of the video output stage, locate the components of thevideo output stage on PCB. Record the identified component symbols in lab record

4 Count the total number of each category of component (like resistor, transistor etc. )identified in video output stage and enter in the record book

5. Get the traced rough sketch of traced component of the video output stage checked byinstructor.

6. Keep an adjustable type table lamp at the back side (solder side) of the PCBUse table lamp of at least 40 W. DON’T keep the bulb very close to the PCB as this mayheat-up the component .DON,T keep the bulb continuously drawn ON for more than 10 to15 minutes to avoid PCB getting heated up.

7 Tracing video output stage starting from input to output terminals of video output stageby marking the links/and connection between component symbols drawn on the recordsheet at step 3.

8 Referring to the circuit diagram of the video output stage rearrange and redraw the tracedcircuit


Task 2 Identify and measure voltage at test points of video output stage of CTV.

1. Referring to the given circuit of the video output , make the location of the test point on thetraced circuit and on the track side of the PCB using a red colour sketch pen

2. Record the specified voltage levels3 In the test point s marked on the given circuit diagram , the expected / specified voltage is

also given four your reference while making voltage mesurememt.4 Fix the connectors (removed for tracing ) back to the main PCB and get it checked by your


5 In the presence of your instructor , switch on the TV and check it is is working satisfactory.If not, consult you instructor .Be aware that you are working in a very high voltage environment.

6 As demonstrated by your instructor, measure the voltage levels at the test point and recordmeasured values.Do not measure voltage at points / placed other than those marked.

7 Get the recorded voltage at the test point checked by your instructor.8. Switch – off CTV and place the PCB back inside the TV cabinet in its original position .

Get it checked by your instructor.

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EXPERIMENT 35 - IDENTIFY IMPORTANT PARTS IN THE TAPE PATH OF VCR/C/VCPOBJECTIVES

Objectives

On completion of this exercise you shall be able toIdentify the following parts of a given VCR/VCP- supply tension post- static guides- full erase head- impedance roller- tape guides- video head drum- video head tip- capstan roller- pinch roller- audio/control head.-


• Trainee’ tool kit - 1 set • VCR/VCP (different make) –2 Nos(min)


1. The VCP/VCR are to be kept ready on table with their cabinet removed.2. All important parts (video head drum, Audio head . Pinch roller, Capstan, etc.)which are to

be identified by the trainees are to be labeled as 1,2,3……. and so on and the same parts ofother VCP should be labeled differently.

3. A batch of 4 trainees can use one VCP/VCR. (less no. of trainees per batch is preferred ifmore no. of VCP’s can be provided)

4. Interchange the VCR/VCPs between batches in order that the trainees do the exercises inall available VCPs .

5. Arrange parts of VCP/VCR mentioned above, for more familiarisation to the trainees.

Procedure

1. Record the make ,type and the model of the given VCP on O&T sheet.2. Select a labeled part, referring to the service manual of the VCR/VCP identify the name of

the part and record the same in the O&T sheet3. Repeat 1,2 and for other VCPs.4. Get your work checked by instructor.

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EXPERIMENT 36 - IDENTITY THE SERVO COMPONENTS IN VCR/VCP

Objectives

On completion of this exercise you shall be able to• Identify the following parts of a given VCR/VCP - drum FG

- drum motor- Capstan motor- Capstan FG- drum pulse pickup- control head-

Requirements

Tools/Equipments/Instruments

• Trainee’s tool kit

• VCP (different make) – 2Nos(min)


1. The VCP/VCR are to be kept ready on table with their cabinet removed.2. All important parts which are to be identified by the trainees are to be labeled 1,2,3,……

and so on and the same part of other VCP should be labeled differently . If spare /defective parts are available it may be issued to trainees for better understanding.

3. A batch of 8 trainees can use one VCP (less no. of trainees per batch is preferred if more noof VCP’s can be provided.)

4. Interchanging the VCPs between batches in order that the trainees do the exercises in allavailable VCP/VCR .

5. Arrange some of the servo components for better familiarisation to the trainees.

Procedure

1. Record the make ,type and the model of the given VCP on O&T sheet.2. Select a labeled part, referring to the fig. 1 or the service manual of the VCR/VCP identify

the name of the part and record the same in the O&T sheet3. Repeat 1 and 2 for other VCP/VCRs.4. Get your work checked by instructor.

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EXPERIMENT 37 - IDENTIFY SENSORS AND LIMIT SWITCHES OF A VCR/ CVCP

Objectives


Identify the following parts of a given VCR/VCP

– Cassette in detector

- record tape sensor

- drum rotation sensor- tape end sensor (play mode)

- tape end sensor ( rewind mode)

- dew sensor

- supply reel sensor

- take –up reel sensor- cue head

- tape slack sensor

- tape loading start/end sensors

- loading motor lock

Requirements

Tools/Equipments/Instruments

• Trainee’s tool kit - 1 Set

• VCP (different make) – 2 Nos(min)


1. The VCP/VCR are to be kept ready on table with their cabinet removed.2. If spare/defective parts are available it may be issued to trainees for better understanding3. A batch of trainees can use on VCP/VCR (less no.of trainees per batch is preferred if more

no. of VCP can be provided)4. Interchange the VCPs between batches so that the trainees do the exercises in all the available

VCP/VCR5. Arrange the parts mentioned to have a better familiarisation to the trainees.

Procedure

1. Record the make ,type and the model of the given VCP on O&T sheet.2. Select one of the listed part from the O&T sheet and identify the part in the VCR/VCP

referring to the manual of the VCR/VCP .Mark the location of the part in the O&T sheet3. Lable the marking as 1,2,3,…… and , provide legend in the O&T sheet.4. Repeat 1 and 2 for other components listed in O&T sheet.5. Get your work checked by the instructor.

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EXPERIMENT 38 - GENERAL MAINTENANCE OF A VCR/VCP

ObjectivesOn completion of this exercise you shall be able to• Clean the video head by using video head cleaner• Clean the audio/control head by using a head cleaning agent• Remove dust and oxide deposited in guide rollers• Wipe out oxides dust accoumulated in capstan and the puinch roller


• Cleaning solution/spray -100ml bottle • Trainees tool kit - 1 Set

• Head cleaning tape -1 No. • VCP/VCR (different make) -2Nos(min)

• Clean cloth/chamois leather -1 No. • Feather touch brush(ordinary)-1 No.

Hints

1 The VCR/VCP are to be kept ready on table with their cabinet removed.2 A batch of trainees can use one VCP. (less no. of trainees per batch is preferred if more no.

of VCPs can be provided)3 Interchange the VCP/VCR between batches in order to the trainees do the excercises in all

available VCP/VCR.4 Demonstrate the method of cleaning the video and audio/control head to remove the pinch

roller, clean and refix the pinch roller.

Procedure

TASK 1:Cleaning video head

1 Inspect the video and audio head for their condition record your observation in the O & Tsheet

2 Rotate the video head drum in such a way the head tip is positioned in a convenient positionto approach for cleaning.

3 Apply the head cleaning solution through a clean cloth or spray the solution over the headtip.

4 Clean the tip with gently with an horizontal movement (similar to tape movement) usingclean cloth as demonstrated by your instructor

5 Get your work checked by instructor6 Repeat step 2 to 5 for other head tips in the drum.7 Play a tape and confirm good working of the VCR/VCP.

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TASK 2: Cleaning audio/control head

1 Inspect the audio and control head for their condition record your observation in the O&Tsheet

2 Apply the head cleaning solution through a clean cloth or spray the solution over the headtip.

3 Clean the tip gently with an horizontal movement (similar to tape movement) using cleancloth demonstrated by your instructor.

4 Get your work checked by instructor.

TASK 3: Cleaning capstan, guide posts and rollers

1 Inspect the capstan, guide post and the rollers for their condition. Record your observationin the O&T sheet.

2 Apply the cleaning solution through a clean cloth or spray the solution over posts androllers.

3 Clean the posts and rollers using clean cloth demonstrated by your instructor.4 Get your work checked by instructor.

TASK 4: Cleaning Pinch roller and rubber components

1 Record the make, type and model of the given VCP on O &T sheet.2 Identify the pinch roller and observe for any deposit of oxide/dust layers record the

observation in the O&T sheet.3 Remove the pinch roller as demonstrated by your instructor.4 Wipe off the deposits with a clean cloth dipped with cleaning liquid.

Some cleaning liquids corrode the rubber surfaces hence always test the cleaning solutionson some waste rubber components before use.

5 Get your work checked by instructor.6 Refix the pinch roller as demonstrated by your instructor.7 Get your work checked by the instructor.8 Repeat th step 2 to 7 for other belts/rubber components used in the VCR/VCP.

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EXPERIMENT 39 - IDENTIFY AND OPERATE THE CONTROLS OF A COMPACT DISCPLAYER

Objectives:

On completion of this exercise you shall be able to• Identify the external switches, controls and sockets of a CD player• Interconnect and tune CD-TV, CD-amplifier setup• Play a compact disc (audio/video) through a CD player


• Audio/Video CDs -1No/Batch • Trainee’s Kit -1 set

• RF connecting cord -1No/Batch • CD Player audio/video -1No/Batch

• Colour Television receiver -1No/Batch

Hints

1 Trainees may be divided into small batches according to the number of CD players available.This excercise canbe performed either with Audio CD player/Video CD player.Preferrablywith both.

2 The instructor shall demonstrate the use of various controls and input/output sockets. Heshall demonstrate the method of interconnecting the CD to Audio amplifier/TV.

3 Instructror shall label the controls, switches and sockets before the excercise for the traineesto identify and provide a copy of the operating manual of the given CD player to thetrainees.

Procedure

Follow the procedureadopted by the Instructorduring demonstration toperform the steps given below.

TASK: Audio CD Player

1 Select a labeled part and identifyits name and function of the givenCD player referring to theoperating manual. Record thedetails in the O&T sheet.

2 Repeat step 1 for all the labels.3 Get your work checked by

instructor.

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4 Inter connect the CD player ( Audo / Video ) to an audio amplifier as shown in the fig.1.Record the sockets and specifications of cable used for inter-connection in O & T sheet.

5 Switch on the CD player and the audio amplifier.6 Insert the CD in the player and play the CD as demon strated by the instructor7 Get your work checked by instructor.8 Operate other controls available on the CD player as recorded in table1 of the O&T heet

and reconform the functions.9 Get your work checked by instructor.

TASK 2: Video CD player

1 select the labeled part and identifyits name and function of the givenCD player referring to the operatingmanual. Record the details in theO&T sheet.

2 Repeat step 1 for all the labels.3 Get your work checked by instructor.4 Interconnect the CD Player (video

CD) to a CTV as shown in the Fig.25 Get your work checked by instructor.6 Switch on the VCD player and the

CTV.7 Switch the TV to AV mode.8 Play the VCD.9 Operate the other controls available

on the CD player as recorded intable2 of the O&T sheet and conformthe functions.

10 Get your work checked by instructor.

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EXPERIMENT 40 - IDENTIFY DIFFERENT EQUUIPMENTS AND MODULES USED IN CATVSYSTEM

Objectives• Identify the equipments/modules used in cable TV• Identify cables and connectors used in cable TV• Identify the components used in cable TV• Masure the signal strength by using signal strength meter.


• RG 6 cable with connector -as reuired • TVRO -1 No

• RG 11 cable with connector -as reuired • Modulator -1 No• Co-axial cables -as reuired • Combiner -1 No• F connectors -as reuired • Line amplifier -1 No• RCA connectors -as reuired • Splitters -1 No• Audio Video cable -as reuired • Power divider -1 No

• Signal strength meter -1 No• PDA -1 No• Bullet amplifier -1 No• Cable equalise -1 No• Attenuator -1 No

Hints

Group the Equipments/Modules, components separately. Each group of trainees have tobe supplied one set of items. Instructor has to ensure all the equipments/modules are pastedwith specification.

Procedure

TASK1 : Identify and record the specification of the CATV Equipments/Modules

1 Pick a CATV module from the group of modules given to you and record the name andspecifications in table 1 of O&T sheet.

2 Record the input and output connector details of the equipments in the subsequent columnsof the table1 of O&T sheet.

3 Get the recorded information cheked by your instructor.4 Repeat the steps 1 and 2 for all other equipments given to you in the table 1 of O&T sheet.

A sample entry is made in table 1 of the O&T sheet for your referance.5 Get the recorded information cheked by your instructor.

TASK2: Identify and record the specification of CATV cables and connectors given to you

1 Identify the names of different cables, and record it in the table 2 of O&T sheet.2 Record the other details/specifications of the component and fill the subsequent col

umns in the table 2 of O&T sheet.3 Get the recorded information cheked by your instructor.

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4 Repeat the steps 1 and 2 for all other equipments given to you in the table 2 of O&T sheet.A sample entry is made in the table 2 for your reference.

5 Get the work cheked by your instructor.

TASK3: Measure the signal strength and identify the frequency band and channel

N.B : Arrange a TV set which can display th efrequency band while changing channels. Insome old model TV receiver sets this facility is not provided.

1 Connect the signal cable to the power divider. Use a suitable cable connector for this purpose.2 Connect the signal strength meter to the power divider signal output and TV receiver to its

respective terminals.3 Get the connections cheked by your instructor.4 Switch on the power divider, signal strength meter and TV receiver.ake sure all the units are

working normally.5 Operate the TV for a particular channel by using manual channel selector or with a remote

control operation. Note down the channel name and band displayed on the TV screen intable 3 of O&T sheet

6 Record the signal strength indicator by the signal strength meter in the table 3 of O&Tmeter.

7 Get the recorded information cheked by your instructor.8 REpeat the steps of 5 and 6 for other channel. Record the corresponding information in the

table 3 of record sheet for each channel.A sample entry is made in the table 3 of O&T sheet for your reference.

9 Coplete the entry by checking all the channel available. Remove the connections and switchoff the unit. Get the recorded information cheked by your instructor.

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EXPERIMENT 41 - INSTALLATION OF CCTV NETWORK

Objectives On completion of this exercise you shall be able to- Identify the basic controls and sockets of a television camera- Connect camera to a TV/monitor- Operate the television camera- Identify basic controls & sockets of a switcher- Install a TV camera, a test pattern generator and a VCR in the control room- Prepare and lay long cables (audio and video) from the control room to the monitors- Assemble a CCTV system and operate.

Requirements


• Co-axial cable with connectors -as reqd. • Tools equipment /instruments

• Audio video monitors - 3 Nps • Trainees tool kit -1 No.

• CCTV camera - 1 No. • Television camera /CCTV camera -1No.

• Video test pattern generaor - 1No • Television set/monitor –1No.

• VCR & video cassette – as reqd • Wire stripper –1No.

• Long video and audio cables – as reqd. • Audio video switcher – as reqd.

• Audio distribution amplifier –1 No. • Video distribution amplifier –1 No.


Label all the parts / controls /sockets of TV camera/CCTV camera to be identified by thetrainees , Demonstrate the interconnections of CCTV system used in the exercise. .Demonstrate the operational control of the CCTV camera/ TV camera.

Procedure

Task 1 : - Identify the basic parts , control and input –output sockets of a television camera.

1. choose a labeled part/control/sockets in the camera and identify the name and functionreferring to the manual.

2. Record the name and the function of the identified part in the O&T sheet.3. Repeat sets 1 and 2 for other labels.4. Get the work checked by your instructor.

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TASK 2;- Capturing images through a television camera.

1. Connect the camera out put signale to a TV set/monitor as shown in Fi 1.2. Set the camera iris control to auto position if available or set it in the mid position

manually.3. Get the work checked by your instructor.4. Switch on the camera and the television set, turn the camera towards a well lit object or

window.5. Select AV mode in TV if the camera is connected through audio-video inputs

or tune the television to receive the picture if the camera is connected through an RFinput.

6. Adjust camera zoom lens to tele position ( magnified image on the screen ) and record thefocal length in the Record sheet.

7. Adjust the iris control, focus control for clear and sharp picture through view finder /TV.For precise focusing , always perform the focus adjustment keeping the lens in tele position, i.e. at the maximum magnification of the image.

8. Place a white card in front of the camera (when viewed through camera the card should fill2/3 of frame area) and adjust white balance and record the type of White balance used.Refer user manual of the camera for any suggest method of doing colour balance.

9 Turn the camera towards an object, adjust the zoo lens to wide position (minimum of thefocal length ) record the focal length of the lens


TASK:- 3 Identify the basic parts, controls & input-output sockets of an audio video switcher.

1 Select a labelled part/control/sockets in the switcher and identufy the name and functionreferring to the manual.

2. Record the name and the function of the idenified part in the O & T sheet.3. Repeat step 1 and 2 for other labels.4. Get the work checked by your instructor.

TASK :- 4. Connect a TV camera , Test pattern generator and VCR to CCTV net work

and operate.

1. Choose three location in thebuilding where CCTV monitors areto be installed.

2. Install three audio/video monitorsin these three locations .

3. Choose a location for the controlroom and install the equipment asshown in Fig 2.

4. Prepare long length video (RG 59)and Audio cables to connect thecontol room to the monitors. Laythe cable through shortest possibleroute. Fix the conne ctors at themonitor ends of the cable.The connectors should match the input connectors of the monitors.

Fig 2

TESTOATTERN

GENERATOR& TONE

CCIVCAMERA &

M I C

VCR

AUDIOVEDEO

SWITCHER

VIEDO

(VDA)VIDEO

DISTRIBUTIONAMPLIFIER

(ADA)AUDIO

DISTRIBUTIONAMPLIFIER

AUDIO

SIMPLE CCTV SYSTEM

A= TV STATION 1B= TV STATION 2C= TV STATION 3

4

4

4

4

4

4

4

4A B C

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5. Similarly fix the connectors at the control room end the cables matching the VDA andADA output connectorsAudiodistribution amplifier and video cable and amplifier can be eliminated in case ofusing a single monitor.

6. Prepare short length audio and video cable and interconnect the pattern generator,CCTVcamera and VCR with the audio switch as shown in Fig. 2.

7. Switch ‘On’ all the equipments and watch the different outputs on the monitors by selectingthe source by the audio/video switcher. Install one monitor in the control room to view theselected channel


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EXPERIMENT 42 - DTH RECEIVER

Objectives:

On Completion of this exercise you shall be able to• Install a DTH antenna and receiver• Track the receiver for different channels• Identify the faults in a DTH receiver and rectify them.

RequirementsMaterials/Components Tools/Equipments/Instruments

• DTH receiver (any brand) - 1 No. • Multimeter

• Dish antenna (small) - 1 No • Colour Television receiver - 1

• Wire cutter cum strippers • Connecting Cable (RF SAV)-1

Hints

1. Try to make available the user manual, service manual and circuit diagram of the DTHreceiver used in this exercise.

2. Try to make copies of the circuit diagram of different stages for reference3. Try to arrange dummy kits for identification and tracing practice, since they may be rough

handled by the students.4. Demonstrate each stage separately before asking the students to start.

Procedure:

Task 1: Installation of the antenna and receiver.

1. Select a suitable location (open space) for the antenna.2. Fix the antenna loosely on the stand provided for it.3. Fix the stand without jerking or other owkward movements.4. Never tighten the screws before traking5. Connect one end of the cable to the LNB6. Connect the other end of the cable to the receiver input7. Connect the output of the receiver to the television receiver either using a RF cord or AVcord.

Task 2: Tracking the Receiver

1. Stitch on the DTH Receiver2. Adjust the position of the according to the direction of the satellite (as per the manual)3. Make find adjustment in azimuth and elevation of the antenna so that the signal strength

display shows the maximum.4. The signal strength can also be measured using the meter.5. While making the adjustments, the picture can be viewed on the TC Screen and make sure

maximum picture quality and sound quality.

Task: 3 Trobleshooting the DTH Receiver

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EXPERIMENT 42 - TELEVISION TUMER CARD FOR COMPUTERS.

Objective

On completion of this exercise the learner will be able to:1. Install the hardw are of television tuner card (external type only) in personal computers.2. Instal the necessary software for TV tumer card in computers.3. Identify the preliminary faults in the working of TV tuner card4. Rectify the simple faults in the working of TV tumer card.

Requirements:

1. Personal computer2. Television tuner card – external type3. Television tuner card – internal typeHints:1. Before starting the installation procedure, make sure that the users manual for the tumer

card is available with you.2. Prepare a diagram showing the interfacing connections of the tumercard with the PC.

Procedure

Task 1: To install the external type tuner card in Personal Computer

Make the connections as per the directions available from the instruction manual. Makesure that all the connections are in fact. Connect the input terminals of the tuner card to the RF

output terminals of the satellite (DTH) receiver. Connect the output of the tumercard to the RF

input of the television receiver. Switch on the tumer card and television receiver. Make necessaryadjustments enlisted in the “Menu” to get maximum picture and sound quality. Tune for

different channel either manually on automatically and save them in the memory.

Task 2:

Installation of software for external type tuner card for the Operation of anydevice interfaced to a computer a software called the driving file is needed tobe installed. Generally in the case of tuner card, once the hardware installationis completed, the driving file is automatically get installed without the need forexternal intervention. Anyhow, if the driving file is not available within if,thesoftware for the installation should be made available separately in a CD andinstalled into the PC for the commencement of the operation of the tunercard.

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STANDARD LIST OF ITEMS REQUIRED FOR PRACTICALS IN THE MRRTV LABORATORY

NON CONSUMABLES:

No. Equipment Specification Quantity (Nos)

1. COMPUTER PENTIUN – IV256 MB

with Internal/external modem

and DVD drive 1

2. CATHODE RAY

OSCILLOSCOPE 20mHz dual trace 2

3. ANALOG MULTIMETER 0 – 10000 VAC,

0 – 250 V – DC,

0 to 250 MA 5

4. DIGITAL MULTIMETER 12 digit 3

5. AMMETER – DC 0 to 500 MA 3

6. Voltmeter – DC 0 to 20 V 3

7. DC REGULATED POWER

SUPPLY (VARIABLE) 0 to 30 v, 2 A 3

8. DC REGULATED POWER

SUPPLY (FIXED) 5V, 500 MA 2

9. DUAL POWER SUPPLY + 12 v, 500 MA 1

10. BATTERY ELIMINATOR

(VARIABLE) 0 – 12V, 1A 4

11. FUNCTION GENERATOR 0 to 100 KHz 1

12. INDUCTANCE BOX 0 – 100 MH 1

13. CAPACITANCE BO Microfarads range 1

14. P.A. SYSTEM Amplifier, Microphone,

Loud speaker, Box containing

woofer, Squaker, Tweetor with

cross over network 1

15 AM RECEIVER TRAINER 1

16. FM RECEIVER TRAINER

17. AM RADIO KIT 3

18. FM RADIO KIT 3

19. TAPE RECORDER MONO AND STEREO 2 each

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20. VCR/VCP 1

21. VCD Player 1

22. VHF TUNER TURRET AND

ELECTRONIC TYPES 1 each

23. MONOCHROME

TV RECEIVER Trainer 1

24. MONOCHROME

TVRECEIVER 14"/20"/21" 3

25. COLOUR TV RECEIVER TRAINER 1

26 COLOUR TV RECEIVER 14”/20”/2” (With and ewithout

Remoto control 3

27 TV ANTENA Yagi-Uda 1

28. TV BOOSTER WITH

POWER SUPPLY 1

29. TV TUNER CARD INTERNAL/EXTERNAL 1

30 DTH RECEIVER DISH ANTENNA, LNB,

RECEIVER 1

31. DVD Player 1

32. STABILIZER 500 VA 1

33. Tape – Recorder Trainer 1

34. Storage Cell 12v/4 AH 1

35. CCTV CAMERA 1

36. SPEAKER ASSEMBLY WOOFER, SQUAKER,

INTERNAL, CROSS OVER

NETWORK

No. Equipment Specification Quantity (Nos)

208208


TOOLS

NO. TOOLS SPECIFICATION UANTITY(NOS)

1. SOLDERING IRON 10W/25W50W/100 W 81

2. PCB DRILLING MACHINE Hand / Electrical 1

3. DE – SOLDERING PUMP 2

4. PCB Common purpose 25

5. Bread Board 5

6. Neon Tester 500 v 5

7. Tweezers 6" 5

8. Combination pliers 6" 5

9. Cutting pliers 6" 5

10. Nose pliers (long) 6" 10

11. Heavy duty cutters 2

12. Side cutters 6" 2

13. Screw driver sets 1. Watch makers5/driver set 2. Flat 5/driver set3. Star 5/driverset 444

14. HACK SAW 30 CM x 102

15. Wire strippers 6" 5

16. ALLEN KEY SET Small 1

17. Rheoslat 0 to 1 K – 2, 1 A 1

18. Mirror with stand for

(TV servicing) 1

CONSUMABLE

No. Components Specification Quantity

1. Resistors ¼ W, ½ W, 1W, 2W

All values 20 Nos. each

2. Wire wound resistors Different waltages 10 Nos. each

3. VDR 2

4. LDR 2

5. Potentice meter (Linear)

(Log) 33

6. Thermistor 2

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2) Electrolytic3) Mica4) Paper All standard values 25 Nos. each22

8. Capacitors – GangTrimmer,Padder 4 each

9. Coils Medium wave and shortwave antenna coilsMW andSW oscillator 5 each

10. Transformers 6 v6-0-6v, 9-0-9v12-0-12v 2 NosDriver 2JFT 3SM transformer 2L.O.T. Black and white and colour 2

11. Diodes 1 N series 25 Nos0 A 79 cachTV 20 1

12. Diodes 1) Pin2) Shottkey3) Gunn4) Impatt5) Trapatt6) Photec diode 1 each

13. LED 1) Single colour 20 Nos2) Bi colour 10Nos.3) Tri colour. 5 Nos4) Infra red .5 Nos.

14. Laser diode 1 15. Zener diode 6.3 v/9.2 v 10 16. FET,

MOSFET,UJT,SCR,DIACTRIAC 1 each

17. Relay 12v, 6v, 24v 2 each 18. Transistors (low frequency) BC seriesBF 20 each

78


210210


High frequency BF. series2 N series 5 each

19. Power transistors AC seriesBV seriesBD series2N 3055SL 100SK 100 10 each

20. Photo transistor 221. LCD 322. Optic coupler 323. CCD 124. Seven segment Display 325. Intergrated circuitAnalog 555 5

741 57805, 7812 3 each7905, 7912 3 each

Digital Logic gates74 series 2 each

26. MultiplexerDemultiplexerA/D & D/A convertorFlip Flop, counters 2 each

27. JCS used in yourTV sets/CD player/Compact Disc/DTH As required

No. Consumables Specification Quantity(Nos.)

1. Copper Clad board 2 sheets2. Copper sulphate 1kg3. Wire a) Single bad

b) Three corec) Flexible 10 m each

4. Solder 100 gms 5 roll5. Flux 50 gms 5 boxes6. Insulation tape 2 roll7. Pen cell 1.5 v 12 Nos.8. Bulb 40 w/60 w 3 each


211211211


Part IVAppendix

212212


REFERENCE

1. Principles of Electronics-V.K.Mehta

2. Electronic Communication systems-Kennedy

3. Basic Radio and Television -S.D.Sharma

4. Electronic Communication-Sanjeeva Gupta


6. www.radiodesign.com

7. Monochrome and colour Television - R.R.Gulathi

8. Modern Television Practice - R.R.Gulathi

9. Audio and video Engineering -R.G. Gupta

10. ww.cd-info.com

11. www.play-hookey.com
