Check Pam Circuits - LG T5100 Service Manual

4. RF PART TROUBLESHOOTING

4.3.5 Check PAM circuits

Checking Points
U709
GSM Out DCS Out
Tx PAM Circuit Diagram
Figure 68. PAM Circuit
APC
- 82 -
Checking Flow
No
Similar
Fig 69?
Yes
GSM Out 33dBm?
DCS Out 30dBm?
Yes
Tx IQ signals are OK.
Go to the next stage
Waveform
Figure 69. PAM Control Signal
Redownload
The Phone S/W
No
U709 is out of
order.
change U709