Samsung NA-C10 Service Manual page 6

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