XIEGU X108G, Service Manual

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4.2.7 Modulation audio signal amplitude adjustment
Required machines and its settings
Machine Setting specs
Audio frequency generator Frequency:1kHz Amplitude:100mV-Vpp
50W RF load
1) Set the receiving frequency of X108G to be 14.25000MHz, [USB] mode.
2) Connect the RF load to the antenna port of the X108G.
3) Unplug the TX signal line from small signal board to the power amplifier board.
4) Measure the amplitude of the test point TP10 with oscilloscope.
5) Press PTT of hand microphone, adjust PotentiometerRW4 to make the amplitude of test point be
50mV-Vpp.
4.2.8 SSB mode carrier suppression debugging
Required machines and its settings
Machine Setting specs
Audio signal generator Frequency:1kHz Amplitude:100mV-Vpp
Spectrum analyzer Central frequency:14.25MHz BW:10MHz
50W RF load
Test point TP10
Potentiometer RW4