[Elecraft] K2 Temp. compensated PLL mod

[Larry - WA2DGD]

Hello all,

Yesterday I did the BFO Toroid and PLL Xtal upgrade and the Temperature
Compsensation Mod to K2 #`1672.
The first step is to write down all the filter BFO frequencies. Well instead
of recording the actual frequency, I always record the 3 digit BFO control
parameter. I did the mods, all went well, and then I re-entered my BFO
control parameters.
Well I had quite a surprise.. USB was receiving LSB and vice versa, and CW
sounded like a direct conversion rcvr, I heard both sides of the cw signal
and my filters were totally screwed up.
Rather than going into a complete panic, I pulled out the KSB2 SSB manual
and entered the BFO Frequencies given in the manual as a starting
point.....everything went back to normal and I was able to use spectrogram
to set up my filters as before...now my K2 works great again.

My question is this... do these mods alter the relationship between the BFO
frequencies and the BFO control parameters? After the mod, my BFO control
parameters are significantly different than the pre-mod numbers. The K2 is
working great but I'm curious as to what happened.

Thanks,
73
Larry
WA2DGD
K2 #1672
ARCI QRP #11215
NJ-QRP# 395