Gsm900 Receiver - Samsung SGH-E840 Service Manual

3-2-2. GSM900 Receiver

CONTINUOS RX ON
RF INPUT : 62CH
Cell power : -50dBm
NORMAL CONDITION
c atch the channel?
YES
F100 CHECK
pin8 ≥ -65dBm?
YES
F100 CHECK
pin17,16 ≥ -
65dBm?
U104 CHECK
pin4,5 ≥ -65dBm?
YES
the power source
of U104
YES
U104 CHECK
Pin15,17 :13MHz
YES
GSM Receiver is ok?
END
NO
NO
resolder or change
NO
resolder or change
YES
NO
L105, L106, C115
resolder or change
NO
check battery contact
NO
check OSC100 and
NO
GSM RX path component
resolder or change
1
CHECK
C100
2
RFS100
3
F100
4
5
6
change
3-21
Flow Chart of Troubleshooting