(Last Updated On: January 10, 2020)
This is the Chapter 8: Color Television Circuits and Signals end chapter exercise in Basic Television – Grob TV as one of the Electronics Engineering topic. In Preparation for the ECE Board Exam make sure to expose yourself and familiarize in each and every questions compiled here taken from various sources including but not limited to past Board Exam Questions in Electronics Engineering field, Electronics Books, Journals and other Electronics References.
Start Grob TV End Chapter Exercise 08
Answers are Underlined
Color Television Circuits and Signals
- a. What are the phosphor colors for the tricolor tube? RGB
- a. What color when added to yellow, will produce white? Blue
- b. What color is the complement of blue? Yellow
- c. Green, when added to blue, produces cyan.
- a. Red is the hue of the color.
- b. Pink is different from red in saturation.
- c. Red has a low luminance.
- a. The input to the matrix includes R, G and B video signals.
- b. The output to the matrix includes Y luminance and two color-mixture signals.
- c. The Y signal has 59 percent G video.
- a. Name the three output of the matrix. Y, I and Q
- b. The two inputs to the modulator are I and Osc.
- c. What is the phase angle for the Q modulator? 90°
- d. Which stage has inputs of Y + C signals? Multiplexer
- e. Which resistor has I and Q modulation? Rc
- a. What is the frequency of the chroma bandpass filter? 3.58 MHz.
- b. Name the two inputs to the R – Y demodulator? C and Osc (r-y)
- c. What is the phase angle between B-Y and R-Y? 90°
What is the value of the Y voltage for the following bars?
- a. White: 1.00
- b. Red: 0.30
- c. Green: 0.59
- d. Blue: 0.11
- e. Yellow: 0.89
- a. The hue of the B-Y video signal is mainly blue.
- b. The R-Y phase is in quadrature with B-Y.
- c. The B-Y and R-Y can be combines to form G-Y.
- d. The B-Y is 180° out of phase with the color sync burst.
- a. What is the frequency of the individual cycles in the color sync burst? 3.58 MHz
- b. What is the repetition rate for the complete group of the color sync burst? 15,750 Hz
- a. What is the hue of the color sync burst? Yellow-Green
- b. What is the phase difference between the color sync burst and the B-Y signal? 180°
- c. What is the phase angle of the R-Y video? 90°
Calculate the values for the yellow and blue bars in the following:
- a. Y signal: 0.89 and 0.11
- b. Q signal: -0.39 and 0.31
- c. C signal: 0.45 and 0.45
- a. Compared with 100 percent saturation, a desaturated color have more luminance for the Y signal and less chrominance for the C signal.
- a. What are the practical Baseband frequencies for the color video signal? 0.5MHz
- b. Large areas of picture information is easier to show in color.
- a. What is the exact horizontal line-scanning frequency for color TV? 15,734.27 MHz
- b. What is the exact vertical field-scanning frequency for color TV? 59.94 Hz
- c. What is the exact color subcarrier? 3.579545 MHz
- d. Which frequency is made exactly an odd multiple of H/2? C signal.
- a. The PAL system alternates the phase of the color signal in successive lines.
Fill in the blanks.
1. Brightness variations of the picture information are in the Y signal.
2. The hue 180° out of phase with red is a cyan.
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 MHZ intercarrier sounds.
5. The hue of color sync phase is yellow green.
6. I signal has color information for 1.3 MHz bandwidth.
7. “A fully saturated color is mostly white.” –it is a false statement.
8. The color with the most luminance is yellow.
9. The hue of a color 90° leading sync burst phase is cyan.
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.