Kees,
Why not an external board that takes RF inputs RF out to connector and has
Relay for TR, the four filters 4 more relays for switching and accepts?
the Raduino signals needed:
TX-V+? to signal transmit receive and DC to relays
TX-A, TX-B,TX-C? (filter select)
FYI if those three filter selects could be encoded for 3:8 filter selection or
2:4 decode for filter selection? Its a minor code change in the Raduino?
to do that.? ?Other schemes are possible as well.
Tt be bold and suggest...? ?Make the board the width of the uBitx and?
the right half is the filters and the left has a set of four or more
filters to insert between T2 and the power amp path to replace the 9section
low pass used.? That would help the harmonic issue and fix the spur issue.
The only issue is that as a single board there must be no shared ground
plane and any shared ground or control signals be isolated for rf.
Allison
