[Elecraft] K2 filter alignment problem

[Robert G Strickland]

I have aligned my K2 crystal filters with Spectogram many times, but 
this time I've run into a problem that I can't figure out.

Using Don's [and the manual's] instructions, I can align F1,F2,F3 in 
decreasing bandwidths. All works as per expectations. On F4, the 
alignment goes "ok," [as per Spectogram] but when I use it with 
on-the-air signals, the signal "disappears" and shows up about 900 cps 
lower and in "reverse" orientation [BFO on opposite side]. When the 
signal disappears, I can change filters [F1/F2/F3] and it's right there 
where it should be with the bandwidth getting narrower as expected. But, 
switching to F4, it's gone. I have tried changing the BFO frequency 
throughout its whole range when in F4, thinking that I've aligned it on 
the "wrong" side. No luck. I'm stumped. Any and all suggestions welcomed.

...robert
-- 
Robert G Strickland, PhD ABPH - KE2WY
rcrgs at verizon.net.usa
Syracuse, New York, USA