[Elecraft] K2 xtal filters: pitch changes from one to next

[Vic Rosenthal]

W3FPR - Don Wilhelm wrote:

> The K2 firmware attempts to maintain the pitch of a tuned signal, but is
> limited to an accuracy of about 10 Hz due to the resolution of the D-A
> conversions in the K2.

Forgive me if you've seen this before, but it IS possible to align the K2 so 
that there is no pitch change when changing filters:

You can eliminate the pitch change if you don't mind changing the filter 
bandwidth slightly.  For example, suppose that you have set a filter to 400 Hz 
bandwidth and located the BFO so that the signal is centered in the filter, and 
suppose that the result is that the pitch of the centered signal comes out 10 
Hz. high.  Just change the bandwidth to 420 (or 380) Hz., readjust the BFO to 
re-center the signal and let the K2's magic algorithm do its work.  Chances are 
it will come out on pitch.  I have been able to adjust all of my filters so that 
there is no change in pitch when I cycle through them.

-- 
73,
Vic, K2VCO
Fresno CA
http://www.qsl.net/k2vco