Samsung SCM-7270, Service Manual, Page: 18 / 65

6-1-2 No Output
6-1-3 AM No Sound
Yes
No
Yes
No
No
Voltages at
IIC1(LC1851N) and semi
conductors tuner section
are normal
TCON1 is at
1.5V
±
1.5 on low coverage
7.5V
±
0.5 on high
coverage
Voltage at FET
are normal
Voltage at power supply
section
Check pump charge circuitry(OQ5)
connection or soldering of SCON1,
FCW2, FCON1 soldering of pin77
of LC72362
Replace FET
Yes
No
No
Check pump charge circuitry
(OQ5) connection of SCON1,
FCW2, FCON1 soldering of pin77
of LC72362N
Yes
Voltage
at LC1851N(IIC1) and tuner
semi conductors are normal
(Refer to Schematic Diagram)
Voltage between
TCON1: AM(MW)
Low coverage 0.9V
±
0.5
High coverage 9V
±
0.5
LW Low coverage 0.7 V
±
0.5
High coverage
4.5V
±
0.5
Check loop antenna soldering and
connection of OL1, OL2, OT1,OT2, IT2
Check voltage at power
supply section
6-2 Samsung Electronics
Troubleshooting