LG KE820 - USB connection mode; Calling; Call divert

5. Trouble shooting
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5.12.10 Checking TX I/Q Signals
Checking Flow
U40
I
I
Q
Q
I
Q
I
Q
TX
Checking Points
Figure 19. TX I/Q
Figure 21. TX I/Q Waveform
Figure 20. TX I/Q
NA
C434
R427
0
R431
0
NA
C435
0
R428
0
R430
R426
0
R429
0
C432
NA
C433
NA
I
IX
Q
QX
RF_DA
RF_CLK
Check TX I/Q Signals
Signals are
Normal ?
Replace
Transceiver
PMB6272(U402)
Yes
No
TX Part is OK.
Check Base Band Circuit
or
Re Download S/W and Cal