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Troubleshooting
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No Picture
No picture with all of
input sources
Check signal processing stage and LCD driving stage;
Check RGB S&H signals at test points TP35R, TP35G, TP35B.
Check power supply circuit 15.5V and peripheral circuit.
Check IC501, IC531, IC561, IC9401, IC401, IC301 and peripheral circuits.
No picture with
COMPONENT (YCbCr
480i,575i) input sources
Check Component source input stage;
Check YCbCr signals at 1,2,3 pin of IC101.
Check IC101 and peripheral circuits.
Check sync signals at test points TPGHS and TPGVS.
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Yes
Yes
No
No
Check following steps.
SG: PC
signals and YCbCr(HDTV) signals are A/D converted in IC8201.
Other signals are A/D converted in IC101. They are sent to IC301 and
scaled in IC301. After correcting for picture quality in IC9401 and IC401,
they are sent to IC501, IC531, IC561(sample & hold, D/A conversion).
Sync: DHS,DVS,DCLK from IC301.
SG:
Component signals are selected in IC5201, with PC/AV_SW signal
(Component = Low). The selected signals YCbCr_M signals are sent to
IC101. They are A/D-converted in IC101 and sent to IC301.
Sync: Y_OUT(=G/Y_M) signal from IC5201 is sent to IC5341, sync-separated in
IC5341.
GHS and GVS signals are sent to IC301 via IC5361.
No picture with
COMPONENT (YCbCr
except for 480i,575i)
input sources
Check Component source input stage;
Check YCbCr signals at test points TP82R/82G/82B.
Check IC5201, IC8201 and peripheral circuits.
Check sync signals at test points TPGHS and TPGVS.
Yes
No
SG:
Component signals are selected in IC5201, with PC/AV_SW signal
(Component = Low). The selected signals YCbCr_A/D signals are sent to
IC8201. They are A/D-converted in IC8201 and sent to IC301.
Sync: Y_OUT(=G/Y_M) signal from IC5201 is sent to IC5341, sync-separated in
IC5341.
GHS and GVS signals are sent to IC301 via IC5361.
720p50Hz sync signal is selected in IC6361 and sent to IC5321.
SG:
Description of visual signal flow
Sync: Description of Sync signal flow
