Chapter 3Television Cameras

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Chapter 3Television Cameras

Fill in the blanks.1.

Plumbiconis a camera tube that uses a lead oxide (PbO) for the photoconductive targetplate.2. Camera signal output without sync is callednon-composite video.3. A low-contrast picture in which white seems flat and lacking in detail suggests a

low beam current.4. APlumbiconis a camera tube that has a minimum lag.5. The part of the invisible spectrum where camerapickup tubes have the greatest output is theyellow-green.6. Precise scanning size and linearity are most important in

a single-tube color pickup.7. Beam alignment magnets for the camera tube are adjusted while rocking which control theelectricalfocus.8. Special effects and production switching are done by the

SEG.9. The gamma of the picture tube is

2.2.10. If the camera cannot be placed far away enough to include everything in the scene, changethe lens to onewith ashorter focal length.11. A typical value of vidicon dark current is

0.2

A.12. A lens has an 8-cm focal length and 4-cm diameter. Its f rating is

2.

Chapter 6Scanning and Synchronizing

Fill in the blanks.1. In the sawtooth waveform for linear scanningthe complete cycle includes trace and retrace.2. Given a 635-

s vertical retrace time, the number of complete horizontal lines scanned during verticalflyback is10.3. One-half line spacing between the start positions for scanning even and odd fields produces

exactinterlacing.4. The number of lines scanned per frame in the raster on the picture tube screen is

525.5. In the frame for which interlaced scanning is used, alternate lines are skipped during vertical

scanningbecausethe vertical scanning frequency is doubled from 30 to 60 Hz.


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6. If the horizontal flyback is 10%, this time equals6.4

s.7.

The

keystone effect produces a square raster- it is afalsestatement.8. The width of a vertical sync pulse with its serrations includes the time ofsix half-lines, or three lines.9. Sawtooth generator circuits produce the scanning raster, but the sync pulses are needed for

timing.10.

31,500 Hz for the vertical scanning frequency is awrong

assertion.Chapter 8Color Television: Circuits and Signals

Fill in the blanks.1. Brightness variations of the picture information are in the

Ysignal.2. The hue 180

out of phase with red is acyan.3. Greater p-p amplitude of the 3.58-MHz chrominance signal indicates more

saturation.4. The interfering beat frequency of 920 kHz is between the 3.58-MHz color subcarrier and the

4.5 MHZintercarrier sounds.5. The hue of color sync phase is

yellow green.


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6.

Isignal has color information for 1.3-MHz bandwidth.7.A fully saturated color is mostly white. it is a

falsestatement.8. The color with the most luminance isyellow.9. The hue of a color 90

leading sync burst phase iscyan.10. The average voltage value of the 3.58-MHz modulated chrominance signal is

the brightness of the color.11. The second IF value for color in receivers, for any station, is

3.58 MHz.12. If the 3.58-MHz C amplifier in the receiver does not operate, the result will be

no color.

Chapter 10From the multiple choice questions:1. How many octaves is the frequency range of 1 to 8?32. Which system can be used for both recording and playback?VHS3. How many TV fields are recorded on one slant track of tape?14. The video heads rotate at high velocity to increase thewriting speed.5. A typical frequency for the FM luminance signal in VCR recording is

3.5 Mhz.6. Which of the following applies to the color-under technique?Chroma frequencies are reduced.7. What oscillator frequency is needed to heterodyne 629 khz up to 3.58 Mhz?4.21 Mhz8. A comb filter is used tocancel chroma crosstalk.9. Switching for each field is required for thevideo heads.10. Servocontrol of speed and phase is used for the

video scanner head.11. The part that rotates to meter o the tape at constant speed is

capstan.12. To make the tape speed the same in playback as in recording, the tapespeed is regulatedby thecontrol-track pulses.13. Tilting the video head gaps is necessary with thezero guard bands.14. Which system uses a laser light beam for playback?VLP15. In the CED system, the disk capacitance varies with the


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pit depth.Chapter 111. The modulated picture carrier wave includes the composite video signal as thesymmetric carrier levelwithout the lower envelope.2. Which of the following statements is true?

Negative transmission means that the carrier amplitudedecreases for black.3. With a 2 Mhz video signal modulating the picture carrier signal for channel 4 (66 to

72 Mhz), which of thefollowing frequencies are transmitted?67.25 Mhz carrier frequency and 69.25 upper side frequency.4. With a 0.5 Mhz video signal modulating the picture carrier,both upper and lower side frequencies aretransmitted.5. In all standard television broadcast channels, the difference between the pictureand sound carrierfrequencies is4.5 Mhz.6. The difference between the sound carrier frequencies in two adjacent channels is6 Mhz.7. Line-of-sight transmission is a characteristic of propagation for theVHF band and higher frequencies.8. In channel 14 (470 to 476 Mhz), the 3.58 color signal is transmitted at

474.83 Mhz.9. The difference between the sound carrier and color subcarrier frequencies is0.92 Mhz.10. The maximum deviation of the FM sound signal, in kilohertz is25 kHz.Chapter 121. Contrast of pictureVideo amplifier2. Audio signal outputFM detector3. Gain control of RF and IFAGC


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4. IF conversionMixer5. Synchronization of pictureSync separator6. Brightness of raster

High-voltage supply7. DC electrode voltagesLow-voltage supply8. Snowy pictureRF amplifier9. Adjacent-channel selectivityIF wave traps10. Baseband video signalVideo detectorChapter 141. Which of the following applies for a monochrome picture?Chroma amplifier off.2. Which of the following is not tuned to 3.58 Mhz?

Video preamplifier3. The contrast control is in the

Y video amplifier.4. The color level control is in theBPA.5. The color oscillator does not operate. The trouble isno color.6. The balance for Y video signals to the three guns in the picture tube is set by thedrive controls.7. Which needs a 0.8

s time delay?

Y video.8. The output of the burst separator feeds theAFPC for color oscillator.9. The output of the color oscillator feeds thecolor demodulators.10. Drifting color bars in the picture indicate trouble in theAFPC for color oscillator.11. The beat frequency between the 3.58 color subcarrier and the 4.5 Mhz sound signal is0.92 MHz.12. Which control varies the phase angle of the color video signal?Tint13. Which of the following stages has the bias from the AGC and color killer circuits?

Chroma BPA.14. Which of the following stages must be on during horizontal Flyback time?Burst separator.15. A crystal-ringer circuit is used for theAFPC on color oscillator.Chapter 151. Which of the ff is a midband cable TV channel isA or 14.2. Coaxial cable for distribution systems has an impedance of150 ohms.


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3. The cable converter output for the TV receiver is usually on channel3.4. A tap for the subscriber drop line has ahigh tap loss.5. The most popular plug for the RG-59U coaxial cable is theF connector.

6. Which of the ff is true?Weak signal causes snow in the picture.7. The upstream signal in two-way cable systems has the frequency of5 to 30 MHz.8. A typical value for the IF signal, in megahertz, for up-down cable converter is612.75.9. Frequency synthesis is used for theVCO in the up-converter.10. For in-band descramblers, the decoding pulses are sent on thesound carrier.11. A trunk cable run has a loss of

20 dBmV. To make up for this loss, the voltage gain of the next amplifiershould be at least10.

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Chapter 3Television Cameras