I was trying to find the instability on 40m when I think I overdrive the "Speaky" releasing some smoke, OK it was not actually smoke but for sure something bad happened and now although it looks like I have transmission signal (didn't tested any longer) I don't have reception (but have audio) and I can ear the mic audio in the output speaker... something I couldn't earlier, so it can't be that bad....
Without further testing I dare to say that the problem is near pin 24 (see schematic,) be it further down or up on the tx/rx switching part. At least T30 isn't conducting during RX, that's why audio bypasses to the balanced modulator and I can listen to it on the speaker, so in that order of idea the balanced modulator is working also.... that leaves T27 to be a good candidate to the recycle bin....
Eventually it can be one of the switching diodes reversing near the mixer (not shown in this part of the schematic) but I would bet more on T27...
Well, more fun for the weekend...
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