Sanyo M4G-3000 Service Manual page 27

Electrical Adjustments
PC/AV-VIDEO ADJUSTMENT-1
Presetting
1. Input the 16-step gray scale video signal and com-
puter signal.
[PC/AV-VIDEO ADJUSTMENT]
2. Connect an oscilloscope to test point "TP512" (+) and
chassis ground (-).
3. Enter to the service mode, select item no. "15" and
change data value to adjust "b" to be 1.8 ±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 3.90 ±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 "TP511" (+) 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 3.90 ±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 "TP513" (+)
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 3.90 ±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.
white level
(b)
white level
(a)
black level
PC/AV-VIDEO ADJUSTMENT-2
[PC-VIDEO ADJUSTMENT-2]
1. Receive the 16-step grey scale computer signal.
2. Set to COMPUTER mode.
3. Connect an oscilloscope to test point "TP512" (+) and
chassis ground (-).
4. Enter to the service mode, select item no. "15" and
change data value to adjust "b" to be 1.90 ±0.01Vp-p.
[AV-VIDEO ADJUSTMENT-2]
9. Receive the 16-step grey scale video signal.
10. Set to VIDEO mode.
11. Connect an oscilloscope to test point "TP512" (+)
and chassis ground (-).
12. Enter to the service mode, select item no. "15" and
change data value to adjust "b" to be 2.10 ±0.01Vp-p.
(b)
(a)
S/H CLOCK ADJUSTMENT
1. Receive the 16-step gray scale computer signal.
2. Set to COMPUTER mode.
3. Connect an oscilloscope to test point "TP512" (+) and
chassis ground (-).
4. Enter to the service mode, select item no. "3" and
change data value to adjust "a" to be maximum.
-27-
white level
white level
black level
(a)