Canon D78-5132, Service Manual

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2.10 PC/AV-Video Adjustment-1
Presetting
1. Input the 16-step gray scale video signal and computer signal.
[PC/AV-video adjustment]
2. Connect an oscilloscope to test point “TP503G” (+) and chassis ground (-).
3. Enter to the service mode, select item no. “15” and change data value to adjust “b” to
be 1.5 ±0.01Vp-p at each VIDEO and COMPUTER mode.
4. Select COMPUTER mode, select item no. “12” and change data value to adjust “a” to
be 4.00 ±0.01Vp-p.
5. Select
VIDEO
mode, select item no. “12” and change data value to adjust “a” to be
4.00 ±0.01Vp-p.
[R-video adjustment]
6. Connect an oscilloscope to test point “TP501R” (+) and chassis ground (-).
7. Enter to the service mode and select
COMPUTER mode.
8. Select item no. “13” and change data value to adjust “a” to be 4.00 ±0.01Vp-p.
9. Select
VIDEO mode and item no. “13” and change data value to adjust “a” to be 4.00
±0.01Vp-p.
[B-video adjustment]
10. Connect an oscilloscope to test point “TP505B” (+) and chassis ground (-).
11. Enter to the service mode and select
COMPUTER
mode.
12. Select item no. “14” and change data value to adjust “a” to be 4.00 ±0.01Vp-p.
13. Select
VIDEO mode and item no. “14” and change data value to adjust “a” to be 4.00
±0.01Vp-p.
Part 3: Adjustment
3-12
(a)
(b)
black level
white level
white level
Fig. 3-8