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Flow Chart of Troubleshooting
3-21
3-2-3. PCS Receiver
CONTINUOS RX ON
RF INPUT : 698CH
Cell power : -50dBm
NORMAL CONDITION
catch the channel?
CHECK
L100,L101,C101
NO
1
YES
PAM100 CHECK
pin12
≥
-65dBm?
RFS100
resolder or change
2
NO
YES
PAM100 CHECK
pin21
≥
-65dBm?
PAM100
resolder or change
NO
3
U100 CHECK
pin20,21
≥
-65dBm?
YES
F102,C125,
C124,C126,L106
resolder or change
NO
4
YES
check UCP300
NO
the power source
of U100
5
6
YES
check OSC100
and
change
U100 CHECK
Pin34,35
:26MHz
NO
YES
END
GSM Receiver is ok?
GSM RX path component
resolder or change
NO