This sounds very interesting.
Are there receive capabilities below 3mhz? I thought the IQ quadrature outputs did not go low enough on the si5351.
Does it matter what the envelope response times are of Q6? I note that these may vary depending on what transistor is used and whether the recently suggested mods have been made?
Presume the code could be extended to do cw also with these mods?
As an aside I have added an extra output socket that takes the IQ outputs straight out for binaural mode listening that works for ssb. a little light on volume (no vol control) but ok with earphones.