开云体育

Hello friends,

Despite the fact that almost everyone waiting CESSB for QMX, I want to ask about QCX mini.

Past weekend I work portable with QCX mini and QMX and noticed how nice sound side-tone in QMX and how claps during keying in QCX mini. My QCX mini has the latest board, probably V4 with required adjustments from QRP-Labs (C22 is 1uF). This problem is discussed recently but I was not able to find working solution except already implemented by REV4 board.

I know about detailed description in the 4.8 Audio amplifier section. I already replaced C22 to new one from Murata with the same nominal 1uF but this did not help.

What you could advice to solve this clapping during keying? I can use smaller 0.1uF but I don't want to louse sensitivity on 20m band.

If you need more info, I can record a video how this sounds.

Whay I need QCX when have a QMX. Ok, I like how sounds direct conversion RX =)

Hello, Daniel

Thank you for answer, I did the same modification for key jack board. Grounding audio jack via capacitor on REV3 board produces huge hiss noise due to changed oamp type and as a result I de-soldered this capacitor. But this changes used to protection from RF coming to RIG via key or headphones. In my case I hear this strong claps even using shielded dummy load. Thank is why I believe the root cause is RX/TX switch part.