This is the Chapter 6: Scanning and Synchronizing 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 06
Answers are Underlined
Scanning and Synchronizing
- a. Retrace is faster than trace.
- b. V retrace takes more time than H trace.
- a. Interlace scanning require odd number of horizontal lines.
- b. How many horizontal lines are in an odd or even field? 262 and ½
- a. How many scanning H lines are there in a complete frame? 21
- b. How many H lines are there in each field? 10 and ½
- c. How many H lines are there in each V retrace? 3
- a. Flicker is caused by the changes between black and white.
- b. Increasing the vertical blanking rate prevents flicker.
- a. All synchronizing pulses have the same amplitude.
- b. The frequency of equalizing pulses is 60 Hz.
- c. The H sync pulses have a higher frequency than the V sync pulses.
Fill in the blanks.
1. In the sawtooth waveform for linear scanning the complete cycle includes trace and retrace.
2. Given a 635 µs vertical retrace time, the number of complete horizontal lines scanned during vertical flyback is 10.
3. One-half line spacing between the start positions for scanning even and odd fields produces exact interlacing.
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 scanning because the vertical scanning frequency is doubled from 30 to 60 Hz.
6. If the horizontal flyback is 10%, this time equals 6.4 µs.
7. “The keystone effect produces a square raster”- it is a false statement.
8. The width of a vertical sync pulse with its serrations includes the time of six 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 a wrong assertion.