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Thanks Evan, for time being your reply is just what I needed, so thank you very much.
I already got ubitx and already have it working. My first impressions are good. But I already have a list of improvements in my mind. Major thing will be to ad an audio filter, because the selectivity is like something I remember from 1964 wen I got my licence, so now I am to spoiled for that. Next thing is that I'll try to figure the way to ad AGC, preferably before audio chain. I'll also have a look into firmware to see if I can do something about CW operation which is not really good right now.
W0EB (and friends) solution to replace Arduino nano with Teens 4 also seems interesting, but I'll leave that for later, after I've done the improvements, that I have in mind.
73, Lado, S53C