S7-PRO Maintenance Manual (Basic Version V2.1)
INTERNAL
2012-07-20
Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
Page 75 of 97
9.12.7 GSM LB Transmit Calibration Failure
Y
Check the input power of QTR8615
End
No
Check whether the power
supply for QTR8615
(U23) is normal
Replace X1
Replace QTR8615 (U23)
Check the input signal, output signal, and
power supply. If any exception is found,
replace the power amplifier (U47)
No
Yes
Y
Check whether QTR8615
can output the signal
TX_GSM_LB normally
Check whether the
19.2 MHz crystal
(X1) is normal
Check whether the
TX_GSM850_EGSM9 power
output of the power amplifier (U47)
is within the specified range
No
Yes
No
Power on the
board
Yes
Check whether the antenna
switch (U46) works normally
Check the input signal, output signal,
logic control signal, and power
supply. If any exception is found,
replace U46
Maintenance procedures
Yes
Yes
No
