Adjustment Of Video System; Video Level Adjustment (Mb-82 Board); S-Terminal Output Check (Mb-82 Board); Checking S Video Output S-C (Mb-82 Board) - Sony DVP-S320 Service Manual

7-2. ADJUSTMENT OF VIDEO SYSTEM

1. Video Level Adjustment (MB-82 BOARD)

<Purpose>
This adjustment is made to satisfy the NTSC standard, and if not
adjusted correctly, the brightness will be too large or small.
Mode Video level adjustment in test mode
Signal Color bars
LINE OUT (VIDEO) connector
Test point
(75 Ω terminated)
Instrument Oscilloscope
Adjusting element RV401
Specification 1.0 ± 0.02 Vp-p
Adjusting method:
1) In the test mode initial menu "6" Video Level Adjustment, set
so that color bars are generated.
2) Adjust the RV401 to attain 1.0 ± 0.02 Vp-p.
Figure 7-1

2. S-terminal Output Check (MB-82 BOARD)

<Purpose>
Check S-terminal video output. If it is incorrect, pictures will not
be displayed correctly in spite of connection to the TV with a S-
terminal cable.
Mode Video level adjustment in test mode
Signal Color bars
S VIDEO OUT (S-Y) connector
Test point
(75 Ω terminated)
Instrument Oscilloscope
Specification 1.0 ± 0.1 Vp-p
Checking method:
1) In the test mode initial menu "6" Video Level Adjustment, set
so that color bars are generated.
2) Confirm that the S-Y level is 1.0 ± 0.1 Vp-p.
Figure 7-2

3. Checking S Video Output S-C (MB-82 BOARD)

<Purpose>
This checks whether the S-C satisfies the NTSC Standard. If it is
not correct, the colors will be too dark or light.
Mode
Signal
Test point
Instrument
Specification
Connection:
Checking method:
1) Confirm that the S-C burst is 286 ± 50 mVp-p.
1.0 ± 0.02 Vp-p
1.0 ± 0.1 Vp-p
7-2
Video level adjustment in test mode
Color bars
CN005 pin 5
Oscilloscope
286 ± 50 mVp-p
CN005
100µF
+
5
75Ω
100k
±1%
±1%
4
Figure 7-3
Oscilloscope
286 ± 50 mVp-p