29WF50
No
Check IC850 and its peripheral circuit.
Are waveform at pins (7), (8) and (9) of IC850 normal?Yes
(Continued)
Abnormal
Check the peripheral circuits of screen heater (FBT) and the CRT.
Check TU200, SF200 and their related parts.
Yes
17-2
No
Check Q455 and its peripheral circuit.Check IC400 and its peripheral circuit.
BIs IC800 RGB out Normal?
Check IC800 and its peripheral circuit.
No snow noise.
Check pins (6) and (7) of IC800.
YesNoiseSignal
Trouble shooting table
NoSignalNoise
Normal
Noise or signal appear.Is AV1, AV2 or AV3 input normal?
Check IC400, Q401 and their peripheral circuit.
Which does pin (43) of IC400 appear, noise or signal? Which does pin (39) of IC800 appear, noise or signal?
B
No
(Continued)
NO PICTURECheck IC600, L200, TU200 and etc.
Does the snow noise appear on the picture tube at max contrast and brightness control?Check IC1751, L201 and etc.
17-1
Yes
NoNo
YesYes
Trouble shooting table
Snow noise increase.
Does 31V appear at pin (9) of TU200?Check TU200, TP201 and etc.
Does 5V appear at pins (6) and (7) of TU200 (TUNER)?
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