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SAMSUNG Proprietary-Contents may change without notice
Flow Chart of Troubleshooting
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9-25
9-16. GSM900 Transmitter
MOD100 Pin10
>= 20dBm
Resolder RFS100,C100,L102
TX ON (5Level)
MOD100 pin15
>= 18dBm
U103 pin9
>= 18dBm
U103 pin7
<= -11dBm
Resolder L113, C105, C108
Yes
Check U103
pin 2,3,4,5,6 OK?
Resolder or Change U103
Check +VBAT or PAM
control signal
No
No
Yes
U102 pin 1,2,3,4
>= 1V
Check U102 pin5,
15, 17, 20, 31, 38
>=2.8V
Resolder U102
Yes
No
Check & Resolder RFLO
signal, RF26MHz,
RF PSU Part
Check UCP200
END
Yes
Yes
Yes
Yes
Yes
No
No
No
No
Check ANT Switch
control circuit
Check MOD100
pin 13=L, pin 14=H
No
Resolder MOD100
Yes