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Power Amplifier (PA) bias setup
If the PA transistors have been replaced then LK1 and LK2 should be opened. RV2 should be set fully
anticlockwise. Power can then be applied to the transceiver and PTT operated but with no audio input.
RV2 should be carefully adjusted to obtain 0.67 V on TP09. LK2 DC feed to the PA can then be used to
monitor PA current. With PTT active and no applied audio RV2 should be readjusted to obtain 350 mA
current feeding the PA stage. Replace the two links and test with a two tone signal as for driver bias setup.
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