16
16-1
16-2
21BM2GMK2
TROUBLE SHOOTING TABLE
(Continued)
NO PICTURE, NO SOUND
Does noise signal appear at
pin (44) of IC801 ?
NO SOUND
No snow noise.
Does noise or 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
(TP201).
Does noise or
signal appear at
pin (38) of IC801 ?
Check IC801 and
its related circuit.
Does noise or
signal appear at
pins (23) and
(24)of IC801.
Check Q251, Q252
and related circuit.
Check pin (37)of
IC801 and related
circuit.
Check pin (1) of
SF201 and Tuner
related circuit.
Check IC801.
Check C356,
C359 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), (29)
and (44) of IC801.
»
Sound Detector Circuit.
»
Sound Switch and Att.
Control.
»
Audio Output Circuit.
Does signal appear at pins
(2) and (4) of IC302 ?
Check P302 connector of
IC302 and peripheral circuit.
Check Q321, pins(4) and (6)
of IC801 and peripheral
circuit.
Does signal appear at pins(28)
and (29) of IC801?
TROUBLE SHOOTING TABLE
(Continued)
NEITHER VERTICAL NOR
HORIZONTAL SYNCHRONIZATION
CIRCUIT TO BE CHECKED:
»
Sync. Separator Circuit.
NO VERTICAL SCAN
Vertical linearity and size is
abnormal.
Check pins(33) and (34) of
IC801.
DEFECTIVE VERTICAL AMP.
AND VERTICAL LINEARITY
Readjust vertical size.
(Bas Data)
Check IC501.
Check C505 and C509.
Check IC501.
Check R501, R503, R512,
R521, R533 and C533.
Содержание 21BM2GMK2
Страница 18: ...21BM2GMK2 18 WAVEFORMS ...
Страница 20: ...20 21BM2GMK2 CHASSIS LAYOUT ...
Страница 21: ...21 21BM2GMK2 BLOCK DIAGRAM CRT UNIT ...
Страница 22: ...21BM2GMK2 21BM2GMK2 22 23 BLOCK DIAGRAM MAIN UNIT ...
Страница 24: ...25 21BM2GMK2 A B C D E F G H I J 1 2 3 4 5 6 7 8 9 10 SCHEMATIC DIAGRAM CRT UNIT ...
Страница 35: ...39 21BM2GMK2 ...