Cw Signal Shift with Filter Change

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Cw Signal Shift with Filter Change

KG4UFV
I have encountered a problem with my K2.  When I change from Filter 1 to Filter2 in CW mode the cw signal shifts 600hz down in frequency.  Has anyone experienced this before?  
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Re: Cw Signal Shift with Filter Change

Don Wilhelm-4
Is this something that just happened, or has it possibly always been
there unnoticed?  In any case, a change to the BFO frequency of one or
all filters is in order.

The condition should be cured by doing a filter alignment.  I highly
recommend using Spectrogram to do that task.  See my website
www.w3fpr.com - article on K2 Dial Calibration, the filter alignment
info is in part 3 of that article.

73,
Don W3FPR

KG4UFV wrote:
> I have encountered a problem with my K2.  When I change from Filter 1 to
> Filter2 in CW mode the cw signal shifts 600hz down in frequency.  Has anyone
> experienced this before?  
>  
>  
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Re: Cw Signal Shift with Filter Change

Julian, G4ILO
In reply to this post by KG4UFV

KG4UFV wrote
I have encountered a problem with my K2.  When I change from Filter 1 to Filter2 in CW mode the cw signal shifts 600hz down in frequency.  Has anyone experienced this before?  
A slight frequency shift is normal, because the K2 has to shift the BFO to get the filter passband centered where you want it, and then shift the VFO the other way to compensate, but the VFO resolution on the K2 is only 10Hz or so, and the differences don't always cancel out.

But 600Hz is way too much.
Julian, G4ILO. K2 #392  K3 #222 KX3 #110
* G4ILO's Shack - http://www.g4ilo.com
* KComm - http://www.g4ilo.com/kcomm.html
* KTune - http://www.g4ilo.com/ktune.html