Sharp 21HM-10F Manual de serviço - Página 22

Procurar online ou descarregar pdf Manual de serviço para TV Sharp 21HM-10F. Sharp 21HM-10F 32 páginas. Secam b/g, l/l' - pal b/g system colour television

Imprimir página
TROUBLESHOOTING TABLES.
CIRCUITS TO BE CHECKED:
Tuner.
PIF.
Automatic Gain Control.
5V, 32V Power Source.
Noise increase but no
signal is received.
Check the tuner supply voltage
LB and HB must be approx. 5V,
BT must be approx. 32V,and
CH preset data check.
Normal
Check the tuner
AGC at TP201.
Normal
Check pin38
of IC801.
CIRCUITS TO BE CHECKED:
Audio Output Circuit.
NO PICTURE, NO SOUND
Does the noise level increase at max.
Contrast,Brightness and Sound controls?
NO
Does noise or
signal appear at
pin38 of IC801?
NO
Does noise or
signal appear at
pin23 and 24
Abnormal
NO
Check pin 2,4 of
Check pin27
(SA),Tuner
of IC801,Tuner
and related circuit.
and related
NO SOUND
Does signal appear
at pin6 of IC303?
YES
Check Speaker.
Check IC303 and
peripheral circuit.
37
No snow noise.
Does noise or signal appear
at pin40 of IC801?
Check IC801
and its related
circuit.
YES
Check Q401
Q402 and related
of IC801?
circuit.
YES
Check pin37 of
IC801 and
circuit.
related circuit.
NO
Check IC801 and
its related circuit.
NO
21HM-10F
YES