Gsm850 Receiver - Samsung SGH-E840 Service Manual

Flow Chart of Troubleshooting
3-2. RF

3-2-1. GSM850 Receiver

CONTINUOS RX ON
RF INPUT : 190CH
Cell power : -50dBm
NORMAL CONDITION
c atch the channel?
F100 CHECK
pin6 ≥ -65dBm?
F101 CHECK
pin18,19 ≥ -
U104 CHECK
pin2,3 ≥ -65dBm?
the power source
of U104
U104 CHECK
Pin15,17 :13MHz
GSM Receiver is ok?
END
NO
YES
NO
resolder or change
YES
NO
resolder or change
YES
NO
L103, L104, C109
resolder or change
YES
NO
check battery contact
YES
NO
check OSC100 and
YES
NO
GSM RX path component
1
CHECK
C104
2
RFS100
3
F100
4
5
6
change
resolder or change
3-20