LG F3000 Service Manual page 61

4. TROUBLESHOOTING
Checking Flow
Check C503,C504,C505
Check whether FEM
Set as TX mode
RRefer to Graph4-6(a), 4-6(b)
RRefer to Table 4-3
Check RF Level of
FL610.10 (for GSM) & Pin 8 (for
DCS)
Check SW500.ANT, RF with RF
Cable connected.
Check SW500.ANT,RF
with RF Cable disconnected
EGSM-Tx 0.0-0.1V
EGSM-Rx 0.0-0.1V
DCS/PCS-Tx 0.0-0.1V
DCS-Rx 0.0-0.1V
PCS-Rx 2.3-3.0V
For the test,
TX Stand alone Mode is needed.
(PL=5 for GSM, PL=0 for DCS)
Check VC1, VC2, VC3
Yes
Pin10 : ~32.5dBm
Pin 8 : ~29.5dBm
Yes
Open
Yes
Short
Yes
END
Vc1 Vc2
0.0-0.1V
0.0-0.1V
2.3-3.0V
0.0-0.1V
0.0-0.1V
Table 4-3
No
Changing board
No
Go to 4.3.5 Checking PAM
control signal
No
Changing SW500
No
Changing SW500
Vc3 Current
2.3-3.0V 10mA Max
0.0-0.1V ≈ 0mA
0.0-0.1V 10mA Max
0.0-0.1V ≈ 0mA
0.0-0.1V 10mA Max
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