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SAMSUNG Proprietary-Contents may change without notice
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Flow Chart of Troubleshooting
7-
24
7-12. GSM Transmitter
TX ON (5Level)
U100 Pin7
>= 20dBm
U100 Pin11
>= 20dBm
U102 Pin6
>= 20dBm
U102 Pin48
>= 3dBm
OSC100 pin1
>= 6Bm
U101 Pin6, 7, 8, 9
>= 500mV
Resolder CN101, C102
Check U100
pin2=L,pin4=H,pin8=L
Resolder C119, L117
Check U101
pin4 >= 4.0V
pin22, 28 >= 2.7V
Change
or Resolder U100
Check ANT Switch
control circuit
Check & Resolder
RF PSU part
Resolder U101
or check Txcpo(R129)
Yes
No
Yes
Yes
Yes
Yes
Yes
Yes
No
No
No
No
No
No
No
Check U102
+VBATT(pin42,43)
OK?
Resolder or change U102
or check PAM control
signal
Check +VBATT
Yes
No
Resolder R107, R111, R112
Yes
Check U202
END