Samsung MM-18 Service Manual page 24

mm18 3/23/98 3:47 PM
Troubleshooting
6-1-2 FM No Sound
IIC1(LA1851N) and semi
conductors tuner section
Check TUNER PACK B+
6-1-3 AM No Sound
Low coverage 0.9V
LW Low coverage 0.7V
Check loop antenna soldering and
connection of OL1, OL2, OT1,OT2, IT2
6-2
Page 2
Voltages at
are normal
Yes
Yes
Voltage at FET are
normal
Voltage
at LA1851N(IIC1) and tuner
semi conductors are normal
(Refer to Schematic Diagram)
Yes
Voltage between
VT: AM(MW)
0.1
0.1
Yes
No
Voltages at power supply
section
Check pump charge circuitry(OQ5,
No
IQ2) connection or soldering of
SCON1-UCON1, FCON1 soldering
of pin 77 of LC72362
No
Replace FET
No
Check voltage at power
supply section
Check pump charge circuitry
No
(OQ5,OQ4) connection of SCON1,
UCON1 soldering of pin77
of LC72362N
Samsung Electronics