[Elecraft] KX3 sideband cancellation calibration

[Grant Youngman]

Ummm ..don't have a good answer for your specific question.  The last time I did it, I used an XG3 and calibrated each filter on each band (there are actually per-band phase/gain settings for each filter).

If you used an XG1 did you calibrate on the 40M fundamental, or was there enough 2nd harmonic to calibrate on 20M?  I found considerable differences in per-band gain/phase settings.  So it wouldn’t be surprising if the null depth is not quite as good on a band you had not specifically calibrated for.  And in some cases you could still barely hear the alternate sideband — but it was very weak in any case.

I also found that the automatic null routines didn’t always get to the deepest null.  Elecraft says that it’s (60+ dB) good enough, and it likely is from any practical view point.  But it was possible in some cases to improve the null slightly by a +/- 1 count manual adjustment of either the phase or gain setting after running the auto-null routine.  It varied by band and filter, and manual tweaking didn’t always result in any improvement.

Grant NQ5T





> On Dec 26, 2020, at 10:44 AM, Steve Zabarnick <zabarnick at gmail.com> wrote:
> 
> I recently noticed that I could hear the opposite sideband on my KX3. As a
> result I tried using my XG1 to do the sideband cancellation calibration
> described in the KXFL3 manual. During the calibration I could significantly
> reduce the sideband so that it could no longer be heard by ear. But, once I
> left calibration mode, I could still hear the opposite sideband from the
> XG1. I did restart the KX3 to save these settings and confirmed that the
> phase and amplitude settings were saved per filter. Any suggestions?
> 
> Steve N9SZ
> ______________________________________________________________