14U10/15
14U20/25
YES
NO
Check Q205 and related circuit. Check IC801.
Check IC801 and related circuit.
YESYES
No snow noise.Check Q301, pins(4) and (6) of IC801 and peripheral circuit.
Does signal appear at pin(28) of IC801?
(Continued)NO
NO
Does signal appear at pin (40) of IC801 ?
Does signal appear at pin (38) of IC801 ?Check pin (1) of SF201 and Tuner related circuit. Check pin (37) of IC801 and related circuit. Check C356 and peripheral circuit.
NO
NO
19-2
NO SOUNDYES (Signal)YES
Does the noise level increase at max. Contrast, Brightness and Sound controls ?
NO PICTURE, NO SOUND
Does signal appear at pin (44) of IC801 ?Does signal appear at pins (6) and (8) of IC301 ?Check P301 connector of IC301 and peripheral circuit.
Check pin (27) of IC801, Tuner and related circuit.
Normal
TROUBLE SHOOTING TABLE Check the tuner AGC at TP201.
NormalAbnormal
Noise increases but no signal is received.
Check pin(38) of IC801.
Check the tuner supply voltage LB must be approx. 5V. BT must be approx, 32V. And CH preset data check.
Tuner. PIF. Automatic Gain Control. (5V), (32V) Power Source. Sound system pins (28) and Sound Detector Circuit. Sound Switch and Att. Audio Output Circuit.
CIRCUITS TO BE CHECKED: ????CIRCUITS TO BE CHECKED: ? (44) of IC801. ?? Control. ?
NO
Checking the protector circuit.
NO
Normal
Blown out.
ON/YES
Replace the fuse.
Check IC701, D701,C707 and D710.D1001 (Power LED Green) turns on.D1001 (Power LED Red) turns on or turns ON/OFF.
The fuse is again blown out.
YES
Check IC801.
NO19-1Abnormal
NormalNormal
Check F701.
NO RASTERCheck C878.Does horizontal circuit oscillate ?Check CRT connector K1-K5 bias.
Check Secondary Main+B T701 pin (17) voltage (Approx 115V)NormalCheck IC751 and IC801.
Check T701 pin (7) voltage (Approx. 310V at 220V AC)
TROUBLE SHOOTING TABLE
Normal
AbnormalAbnormal
Check R701, R707 and D709.Check R618 and R615.
Check D758, IC702, D762 and IC753.
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