Gsm900 Receiver - Samsung SGH-J600 Service Manual

3-2. RF

3-2-1. GSM900 Receiver

CONTINUOS RX ON
RF INPUT : 62CH
Cell power : -50dBm
NORMAL CONDITION
c atch the channel?
YES
U100 CHECK
pin12 ≥ -65dBm?
YES
U100 CHECK
pin16 ≥ -65dBm?
UCD100 CHECK
pin21,22 ≥ -65dBm?
YES
the power source
of UCD100
YES
UCD100 CHECK
Pin30,31 :26MHz
YES
GSM Receiver is ok?
END
NO
L103,L105,C104
NO
resolder or change
NO
resolder or change
YES
NO
C101,C102,L100
resolder or change
NO
check UCD300
NO
check OSC100 and
NO
GSM RX path component
resolder or change
1
CHECK
2
CN100
3
U100
F100,C100
4
5
6
change
3-23
Flow Chart of Troubleshooting