Hi Conrad,

"SIG RMV" is a function we created that shifts both the BFO and VFO by the same 
small amount in order to shift a spur out of the passband. 

The reason this is effective for many spurs is because they're the product of 
harmonics of the signal sources, not the fundamentals. For example, you may 
hear a spur that results from mixing of the 3rd harmonic of the VFO beating 
against the 9th harmonic of the BFO (any combination is possible). That's the 
nature of high-level mixers in superhet transceivers. 

SIG RMV shifts the VFO and BFO by the same amount *at their fundamentals*, but 
the spurs end up shifted by a multiple of this amount. Using the previous 
example, a 100 Hz shift at the fundamental might shift the VFO 300 Hz and the 
BFO 900 Hz. (Often the multiples are much higher -- I've seen them up to 21.) 
Doing this often moves the spur out of the passband, while having an 
insignificant effect on the filter center frequency (these are fixed because of 
the crystal filters).

You can create SIG RMV entries separately for both the main and sub receivers 
on the K3/K3S.

73,
Wayne
N6KR



> On Dec 26, 2020, at 3:44 AM, Conrad PA5Y <[email protected]> wrote:
> 
> Thanks to G4ZTR I found "SIG RMV" in the Config Menu. It worked a treat. What 
> exactly does this do. I noticed that the passband changed but I was able to 
> restore it by changing the centre frequency. It worked great!
> 
> 
> 
> Many thanks John.
> 
> 
> 
> 73
> 
> 
> 
> Conrad PA5Y
> 
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