1. Given similar power levels, a 2N7000 in place of the antenna relay should work. A few more transistors can isolate the rx signal path. This is the easier of the wins.
2. Timing. A particular sequence of things have to happen. On key down, the rx audio has to smoothly switch off, then the rx amplifiers power should turn off and the bypass caps need to be discharged, the tx circuitry has to power up. The sequence has to reverse on key up.
4. The LPF relays should be constantly powered up (even on rx). These may wear out the relays.
Combining full break-in with multiband is an expensive and extensive option. The ubitx is a child of many compromises.
Has anybody tried to do this with the uBITX?? I have a qrp-labs QCX+ kit
that does it,
and I must confess, I'm getting spoiled.? I tried it with my
TS590S...nope.? Feverishly clacking relays.? Dug an IC706MKII out of the
closet- same deal.? Clack-clack-clack.
