From: [email protected] [mailto:[email protected]] On Behalf Of Jerry Gaffke via Groups.Io
Sent: Sunday, August 5, 2018 12:00 AM
To: [email protected]
Subject: Re: [BITX20] Harmonic performance - SSB vs CW

?

Going forward, I for one would be fine with plug-in LPF's on a rig in this price range.
Should have some way for the Raduino to sense what board is installed.

Those that want electronic switching could add some optional mezzanine board that plugs?
into that same socket, an i2c bus controlling all the relays.

If you remove the relays we have now, might be possible to use those holes
to convert current boards to this scheme.
But hacking current boards to have straps at the output side of the four
bandpass filters is easier, and solves both the trace problem
and the issue of isolation through the relays.

Allison has been recommending band specific filters in place of the 30mhz low pass filter
in front of the first mixer.? ?But I like how simple the rig is now, and would look first for reasons
not to raise the 45mhz IF frequency some.? Alternately, just call it quits at 20 meters.

Also:
Need something better than 2n3904's in many positions.
Perhaps an extra driver stage.
Si5351 should drive the mixers harder.
Si5351 might want to be on the main board.

Jerry, KE7ER