LG KG800 Service Manual page 65

4. TROUBLESHOOTING
Checking Flow
Check C616,C617,C618
Check whether FEM
Set as TX mode
Rrefer to Graph4-6(a), 4-6(b)
Rrefer to Table 4-3
Check RF Level of
FL601.10 (for GSM) & Pin 8 (for
DCS)
Check SW601.ANT, RF with RF
Cable connected.
Check SW601.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=7 for
GSM, PL=2 for DCS)
Check VC1, VC2, VC3
Yes
Pin10 : ~29.5dBm
Pin 8 : ~26.5dBm
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 SW601
No
Changing SW601
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
- 66 -