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QMX HB no side tone, raspy thump

 

Hi all,
I've just finished putting together a QMX rev2 high band. All works well except for no sidetone on tx except "raspy thump". Sidetone is fine into a dummy load and when not in tx, so I assume it must be RF causing problems.?
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I don't have any side tone issues with my kit built QCX-mini on same antenna, so I'm thinking I have a grounding/connection issue within the QMX.
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I've re-flowed and checked connections but I'd be grateful if someone more could point me in the right direct before I damage something. I'm probably missing something obvious.?
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Many thanks.
Roger MW0IDX??
 

UPDATE: I've just re-flowed the solder joints again and I now have a good clean side tone. Power out put is around 3.5 watts, so will try adjusting the LPF for just a little more out put. Any hints?
Amazing little radio, how Hans managed to fit everything in I don't know!?
73
Roger MW0IDX?
 

Which solder joints did you reflow to address the sidetone issue?

I’m still having a strong band-dependent ‘knock’ at the end of each character. Wondering if a bad solder joint could be a cause??

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