Just some quick thoughts on your observations.
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RE: low watts out on 30/20.
They share the LPF pair.
Inspect solder joints, turns on the toroids, capacitors etc.
Fiddle with spreading and squeezing turns on those two as well.
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RE: power output differences
Have you tried different interconnect cables or BNC couplers?
Do you get the same results on the diagnostics with just the dummy load connected to the QMX? Try with both interconnect cables and/or BNC couplers.
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Any chance you have a nearby Ham Buddy that can check the new power meter. Or perhaps you have another radio you know works well?
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Hope it's something simple since the new power meter seems to be showing just about 1/2 of the expected power out?
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