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Further copies of this Report are available from aqa.org.uk

Copyright © 2015 AQA and its licensors. All rights reserved. AQA retains the copyright on all its publications. However, registered schools/colleges for AQA are permitted to copy material from thisbooklet for their own internal use, with the following important exception: AQA cannot give permission to schools/colleges to photocopy anymaterial that is acknowledged to a third party even for internal use within the centre.

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REPORT ON THE EXAMINATION – GCSE ELECTRONIC PRODUCTS – 45401 – 2015

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Principal Examiner’s Report on the 2015 Question Paper for

GCSE Electronic Products (45401)

General Comments.

The paper proved to be accessible to the vast majority of candidates, with a wide range of marks

being awarded. The paper proved to be slightly more challenging than last year’s paper in terms ofthe electronics technical questions, and there were more un-attempted questions this year.Centres had clearly studied the preliminary material with care, and the majority of candidates

performed well with the section A questions. The range, quality and creativity shown in the designand development questions were commendable, with clear drawings and a good level of

annotation in most cases. The safety issues question was particularly well answered. Morecandidates are now explaining and justifying their responses in the short written questions, andcalculation questions were also very well answered.

Section A

Question 1

1(a) This question was well-answered, with many candidates gaining full marks. Most responsesfor the case requirements were very clear, but some circuit requirements were rather basic, suchas writing that the ‘circuit should work’.

1(b) Many candidates scored at least six marks for their initial ideas for the product. There were

many examples of creative and imaginative solutions, and the quality of communication wasgenerally good, with clearly drawn and annotated drawings. Candidates demonstrated creativity in

many different ways, including drawing fun and interesting shapes, use of colour to attract children,and suggesting the use of complex sound and light sequences in the product.1(c) Many candidates appear to have carefully studied the marking criteria, and made sure that

they addressed the criteria in their response, thus giving them access to the higher marks. Case

construction details were addressed very well, as were suggestions of materials that could beused, and there were few generic materials named, such as wood and plastic. The quality of

communication seems to be improving each year, with clear and accurate drawings and sketches,and relevant labelling and annotation. There were some candidates who spent time givingirrelevant details, or whose drawings were difficult to interpret.

1(d)(i) Most candidates gained at least one mark, with one third gaining both marks. As the

question asked how microcontrollers can be used to make toys fun and appealing, simply statingthat the microcontroller can be used to switch outputs on did not warrant full marks.

1(d)(ii) This question was very well-answered. The vast majority of candidates named two, differentspecific output components, but there were some vague input components, such as ‘sensor’ or‘trigger’.

1(e) Some centres had prepared their candidates well for this type of question, and there were

some excellent examples of accurately drawn circuits, with correct symbols and good detail in theannotation. However, there were also some very poorly drawn circuits, where only parts of the

circuit would work. Symbols were inaccurate, and there was little evidence of any technical detail inthe notes.1(f) This question was answered very well, with the majority of candidates gaining full marks. A

wide range of safety issues were discussed in detail and most candidates gave valid reasons for

the safety features that they had identified. There were a few responses that just gave a list ofsafety features; for example no sharp corners, not too heavy and similar, but as the question asked

for a discussion, full marks could not be gained without further clarification.

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Section B

Question 22(a) This question seemed to challenge most candidates with few correctly identifying themicroswitch. A common mistake was confusing the rotary switch with a potentiometer.

2(b) Completing the thyristor circuit diagram by adding switches proved to be difficult for themajority of candidates. Most correctly drew a PTM switch to the resistor, but some then went on to

also connect the PTM to zero volts, thus creating a short circuit. There were also a lot of responses

where the reset switch was connected across the power supply, again creating a short circuit.2(c) A minority of candidates gained full marks for naming the connections of a thyristor. Mostcandidates correctly identified the anode and cathode, but there were many who confused the

thyristor with a transistor, so there were many examples of base, collector and emitter responsesseen.

2(d) Disappointingly only a minority of candidates were able to answer the question about thebistable correctly. A common error was to suggest that it was a device that could be a monostableor an astable.2(e) There were many different suggestions for why membrane switches are suitable for a remote

control, and most candidates justified or explained their responses. There were some candidateswho perhaps did not know what a membrane switch was, but nevertheless attempted the questionafter having studied the picture, and gave some valid reasons.

Question 33(a) The potential divider calculation was well answered, with most gaining full marks. As has been

the case for many years, the question specifically asked for the formula, evidence of working, andthe answer with units and most candidates adhered to the structure. There were some calculationerrors even though a correct substitution had made, and centres are reminded that candidates are

allowed a calculator in the exam.3(b)(i) Most candidates correctly identified the component as a diode.3(b)(ii) This question was poorly answered. Many candidates described the behaviour of a diode,

suggesting it allows current to flow in one direction. However, the question asked for its functionwithin the circuit i.e. to protect the transistor. Also, there were a large number who wrote that thediode was there to protect the buzzer, and not the transistor.

3(c) Few candidates gained both marks for this question. There were, however, many referencesto CAD helping to produce a neat, or small or accurate circuit design, yet this can be achieved bysimply drawing a layout by hand. There were also unjustified or vague responses such as ‘quick’,

‘easy’ and ‘cheap’, which gained no marks.

Question 4

4(a) This question was well answered, with most candidates scoring well. Many correctly

connected the switch and resistor to the power rails, and connected the junction to the input of theintegrated circuit. However, the reset part of the circuit was less well answered, with some

candidates unable to draw another PTM switch and resistor, or correctly connect them to the resetpin of the IC.4(b) Very few candidates understood the purpose of the pull-down resistor in the circuit, with a high

number of unattempted responses. Of those who attempted the question, most seemed to think

that the resistor was there to protect the IC from too much current or voltage. This was a moretechnically challenging question, but surprisingly poorly answered.

4(c) Generally, candidates understood what is meant by switch bounce and the effect it can haveon a counting circuit. There were a number of basic or poorly explained responses, such as ‘it iswhen a switch bounces’, and there were candidates who did not attempt the question at all.

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4(d) Many candidates suggested the use of a monostable, Schmitt trigger or even a delay in a

microcontroller program, but few went on to explain why the addition of these components would

help. Candidates should be taught to look at some of the terms used in questions, and understandtheir meaning; for example, explain, describe, and suggest.

Question 55 This was the QWC question, with candidates being asked to discuss the use of electronic

devices in cars. The topic proved to be more challenging than the health and safety issues

question from last year, and the number of candidates scoring at least six marks was around onethird. There were many excellent responses, with candidates using very clear, concise andfocussed language, and discussing the advantages and disadvantages of these products in detail.

Evidence of candidates planning their answers was seen on several papers. They also mentionedseveral different examples of devices, and not just the two given in the question. Some responses

simply described the use of devices, and did not give advantages and disadvantages to the driver,or just discussed one device. Also, some candidates’ responses were poorly constructed, with very long sentences andcontaining numerous spelling mistakes. Candidates should be reminded that it is good practice to

read through and check their answers if there is time permitting, and correct any mistakes theymay notice.

Question 66(a) Around forty percent of candidates scored at least two marks with this question. Many clearlydiscussed the advantages of using a rapid prototyping process, but there were also candidates

who simply discussed the advantages of prototyping in general. They wrote about testing andevaluating prototypes as part of a development process, and not specifically about the use of, forexample, a 3-D printer or similar.

6(b) This question was generally answered well, with some clearly identified advantages of usinginjection moulding, and many candidates justified or explained their responses. Once again,however, there were many simple and unjustified responses including ’it’s cheap, it’s quick, it’s

easy’. Centres are reminded that this level of response is not worthy of credit at GCSE level.6(c) Many candidates suggested significantly modifying the design of the case rather thanmodifying the former in order to ease production. For example, there were suggestions that the

recess at the top of the case should be removed, or that the top layer be removed completely.There were few who gained full marks for this question, although vacuum forming appears to be aprocess that is very familiar to the majority of candidates.

6(d) The question about the vacuum forming process was quite well answered, with ten percent of

candidates gaining full marks, and around thirty percent gaining at least five marks. The one majorstep that was commonly missed was the clamping, or securing, of the material prior to heating.

Question 77(a)(i) The vast majority of candidates showed that they understood why a polarised component

needs to be correctly connected.7(a)(ii) This was another well answered question, with the capacitor and buzzer being the mostcommon selections. There were a surprising number of resistors and switches circled by

candidates.

7(b) Describing the operation of a monostable circuit proved to be a technically challengingquestion for a high number of candidates. It was not necessary to explain the function of every

component in order to gain full marks, but there were a significant number of unattemptedresponses seen. Marks were available for any clear and relevant point made, so candidates shouldbe encouraged to always attempt a question, or parts of a question.

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7(c) As with the voltage divider calculation, this question was well answered, with candidates

adhering to the structure by clearly writing the formula, showing workings, and giving the answer

with units. Some candidates were not confident when using micro-farad units.7(d) There were a high number of candidates who suggested simply changing the values of theresistor or capacitor in order to change the time period of the monostable. However, the question

asked for a modification so that the monostable could time different processes, and the use of avariable resistor would have been a much better response.

7(e) This question was answered well, with most candidates at least drawing a repeating wave

pattern, and almost half drawing a repeating square wave.7(f) Almost all candidates knew that a buzzer generates a single sound or frequency, and aroundhalf also knew that a sounder can create a range of sounds, frequencies or tunes.7(g) The microcontroller question was well answered, with just under half of the candidates gainingat least five marks. There seemed to be a much higher proportion of BASIC based responses than

in previous years, and candidates seem more confident in attempting this type of question.Common mistakes seen with this question included not turning the LED off, and not having thecorrect timing. The majority included some kind or procedure, or sub-routine, as part of theirsolution. There still remains a number of responses that are not using commands or language thatwould be seen in programming software, and are simple re-writes of the question. For example,candidates write, in a command ‘box’, ‘turn the LED on for two seconds’, rather than ‘LED on 2seconds’.

Mark Ranges and Award of Grades

Grade boundaries and cumulative percentage grades are available on the Results Statistics

page of the AQA Website.

Converting Marks into UMS marks

Convert raw marks into Uniform Mark Scale (UMS) marks by using the link below.

UMS conversion calculator
http://www.aqa.org.uk/exams-administration/about-results/results-statisticshttp://www.aqa.org.uk/exams-administration/about-results/uniform-mark-scale/convert-marks-to-umshttp://www.aqa.org.uk/exams-administration/about-results/uniform-mark-scale/convert-marks-to-umshttp://www.aqa.org.uk/exams-administration/about-results/results-statistics

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Mark Shceme 2015