Model X771
L3 Service Manual
12)
Flash Light
NA
13)
Vibrator
NA
14)
Network
Solution:
A-
Test the conduction power to see if it normal; if normal, test the circuit between the RF test
pad and the antenna to see if it is normal; or else, see the analysis of
“
abnormality of
conduction power
”
.
B-
Test the circuit between the RF test pad and the antenna to see if it is normal are shown in the
following chart;
C-
Check if the contact between the antenna and the antenna spring clip is normal. Deformation
of the antenna spring clip, which will affect coupling of RF signal, further resulting in low
coupling power. This problem can be solved by replacing the damaged component.
D-
Damage of component material in the RF circuit, which can be solved by replacing the
material;
E-
Pseudo soldering of components, which can be solved by repair soldering;
F-
Direction error or position shift of components due to surface mounting, which can be solved
by Properly soldering the components;
G-
Power abnormality caused by abnormal calibration, which can be solved by using proper
Calibration software configuration and instrument.
The repairman can check item by item according to the signal trend in the diagram, so as to
Determine the failure position.
RF_
ANT
