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