Checking Component Video Output R-Y; Checking Component Video Output Y; Checking S Video Output S-C; Checking S Video Output Dc Level - Sony RMT-D107A Service Manual

4. Checking Component Video Output R-Y

(MB-84 board)
<Purpose>
This checks component video output R-Y. If it is incorrect, cor-
rect colors will not be displayed when connected to, for instance,
projector.
Video Encoder (IC252) check in test
Mode
mode menu "0" Syscon Diagnosis
Signal Color bars
COMPONENT VIDEO OUT (R-Y)
Test point
connector (75 Ω terminated)
Instrument Oscilloscope
Specification 700 ± 30 mVp-p
Checking method:
1) Confirm that the R-Y level is 700 ± 30 mVp-p.
700 ± 30 mVp-p
Figure 7-5

5. Checking Component Video Output Y

(MB-84 board)
<Purpose>
This checks component video output Y. If it is incorrect, correct
brightness will not be attained when connected to, for instance,
projector.
Video Encoder (IC252) check in test
Mode
mode menu "0" Syscon Diagnosis
Signal Color bars
COMPONENT VIDEO OUT (Y)
Test point
connector (75 Ω terminated)
Instrument Oscilloscope
Specification 1 ± 0.05 Vp-p
Checking method:
1) Confirm that the Y level is 1 ± 0.05 Vp-p.
1 ± 0.05 Vp-p
Figure 7-6
6. Checking S Video Output S-C (MB-84 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.
Video Encoder (IC252) check in test
Mode
mode menu "0" Syscon Diagnosis
Signal Color bars
CN252 !™ pin
Test point
Instrument Oscilloscope
Specification 286 ± 20 mVp-p
Connection:
CN252
100µF
+
12 Oscilloscope
75Ω 100k
±1% ±1%
11
Checking method:
1) Confirm that the S-C burst is 286 ± 20 mVp-p.
286 ± 20 mVp-p
Figure 7-7
7. Checking S Video Output DC Level (MB-84 board)
<Purpose>
This checks signals for S1 and S2 compatible TV. If they are not
correct, the TV will not switch automatically to letter box, etc.
Video Encoder (IC252) check in test
Mode
mode menu "0" Syscon Diagnosis
Signal Color bars
CN252 !™ pin
Test point
Instrument Digital voltmeter
S-terminal 0 V: 0 Vdc
Specification
+0
S-terminal 5 V: 5.0 Vdc
–1.5
Connection:
CN252
100µF
+
12 Digital voltmeter
75Ω 100k
±1% ±1%
11
Checking method:
1) In the test mode initial menu "0" Syscon Diagnosis, select S-
terminal 0 V.
Confirm that the voltage at CN252 !™ pin is 0 Vdc.
2) Press any key to select S-terminal 5 V.
+0
Confirm that the voltage at CN252 !™ pin is 5.0
–1.5
7-3

7-4. Adjustment Related Parts Arrangement

MB-84 BOARD (Side A)
RV251
VIDEO
LEVEL
ADJ
MB-84 BOARD (Side B)
HS-930SU BOARD (Side A)
Vdc.
CN251
9
1
IC206
8 7
1
14
CT201
SYS CLK
(27 MHz) ADJ
25 1
CN252
24 2
7-4 E
CN201
1
4
6
8
9
11
12
14