XIEGU
Product Maintenance Manual G90/G90S Portable Short-Wave Transceiver
XIEGU All Rights Reserved Version No.: 1.0 2022-07 Page
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Fault phenomenon: High startup current and abnormal operation of the whole device
Maintenance methods:
The fault is mainly caused by the abnormal switching of the
transmitting and receiving voltages, which leads to the incomplete
switching of the voltages of the two circuits.
1. Disconnect the transmitting small signal line.
2. Press/ release the hand microphone PTT button, and the
measurement data of each checkpoint shall be as follows:
Checkpoint
Voltage V
Name
B5
+9T
Transmitting 9V voltage
B6
+9R
Receiving 9V voltage
In the receiving state, +9T voltage should be about 0V;
In the transmitting state, +9T should be about 9V, and +9R
should be about 0~0.15V.
3. If the above voltage is abnormal, focus on checking whether the
components in the T/R voltage switching unit are faultily welded or
defective. MOS tube and diode in this unit are damaged a lot.
T/R Voltage Switching Unit
