[Elecraft] BFO Mod, SSB board and so on.

[Paul Barlow]

Dear all,

during the last few days I've put together the SSB board for my K2, after 18
months as a CW only rig. I also got all the  A - B mods in the same order
and I'm starting to do those.

Yesterday I did the BFO mod, and today I added the temperature stability
mod.

My BFO range is adequate, but has a lowest frequency of 4913.12 (i.e. about
.5 kHz too high.

I aligned all my filters using Spectrogram this afternoon, and it seems that
even with the shifted BFO range I can get the filters in the right place for
a 700 Hz side tone. Should I try [adding C174, or should I leave well alone?

I also notice that signals seem much stronger through the OP1 filter than
through the CW filter. Is this normal, is my CW filter attenuating more than
it should (settings OP1, .7, .4 and .2)? If so I've had a deaf K2 for 18
months! But it still hears the band noise when I plug the antenna in - so
how much more gain do I need?

Since I will be working on the CW filter (replacing the crystals) I might
find an improvement (and perhaps I ought to look at the matching
transformers while I'm there?

Finally should I simply set the BFO freq in OP1 SSB to the value I recorded
from the look up table in the SSB board manual, or should I set it up using
spectrogram? I think that it's OK as it is anyway, but I may have just moved
it slightly. Listening on another receiver seems to show OK audio quality on
transmit.

73,

Paul M0CDP K2 #2356 in modification.