Samsung NA-C10, Service Manual

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Samsung Electronics
Troubleshooting
8-3
8-3 Tuner Malfunction (FM/AM)
TZD2(8.2V) Voltage ok ?
Check TUNER IC(LA1836)
pin on. 10 ; 8.2V
pin on. 14 ; 7.2V
AM ; 0V ?
FM VT
LC72131 pin no.20
1.7V 7.5V
Power section defective
Check for
µ
-com IC
Replace LC72131
Check FEP interior
pattern, and any line
disconnections.
No
No
No No
No
No No
Yes
No
No
Yes No
No
Yes
Yes
Yes
Yes
Check MIC6
pin 20 ?
LPF1,2
output ok ?
Yes
AM VT
LC72131 pin 20
0.9V 7V ?
AQI(C4369) Voltage ok ?
PIN NO.8 : 12V
Check the voltage ok ?
TZD3(5.6V) Voltage ok ?
MIC7(LC72131) FM/AM BAND
Switching ok ?
1) Power impaired
so repair defects.
2) LC72131 Oscillator
(HX1 : 7.2MHz) ok ?
3) System line ok ?
LC72131
CONTROL ok ?
Check the LC72131
CONTROL ok ?
Check(TDA7449) function ok ?
QIC1