LG PX8700 Service Manual page 54

PX8700
4.1.2.4 Checking RF Signal path (Mobile S/W, Triplexer, Duplexer)
Test Point
U103
C101
U104
U109
DP101
LG Electronics Inc.
Checking Flow
Check U103 Pin 1
Check if there is
Any Major Difference
◆ Refer to Graph 4.1.2(e)
Check U104 Pin 7,
U109 Pin4
Check if there is
Any Major Difference
◆ Refer to Graph 4.1.2(f)
Check DP101 Pin 2
Check if there is
Any Major Difference
◆ Refer to Graph 4.1.2(g)
RF Signal Path is OK.
See next Page to check
No
Detected Signal? Changing U107
Yes
No
Detected Signal?
Check C101
Yes
No
Detected Signal?
Yes
No
Detected Signal?
Yes
No
Changing DP101
Detected Signal?
Yes
No
Check C1055 &
Detected Signal?
C153
Yes
RX I/Q data signal.
Changing U104 or
U109
Check
C131&C192&
C1062
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