[Elecraft] P3 Broad Birdie & straw men...

[Eric Swartz - WA6HHQ, Elecraft]

There should be no 'holes' with the K3 SIGRMV birdie removal method.

At the specified tuning point we simply shift the VFO and DSP internal 
oscillators a small amount in opposite directions to move the weak 
birdie and still recieve on exactly the same frequency. (Birdies are 
typically the result of mixing of higher harmonics of the internal radio 
oscillators and hence move in multiples of the amount any oscillator is 
moved, pushing them well outside of the receive filter pass-band.)

73, Eric   WA6HHQ

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www.elecraft.com


On 6/13/2011 2:29 PM, David Gilbert wrote:
> Juergen, how exactly does the SIG RMV feature in the K3 "leave holes in
> the band"??  I have zapped several dozen birdies that way and don't have
> any holes at all.  Yes ... there is a sort of "whooshing" sounds as you
> tune across some of them (the ones that required greater shift), but I
> do a lot of contesting and have never experienced any signal drop out
> ... and per my understanding of how SIG RMV works there should not be
> any anyway.
>
> Dave   AB7E
>
>
> On 6/13/2011 12:32 AM, juergen wrote:
>>    The birdie elimination routine is not all that effective and leaves holes in the band. I dont see how a more powerful DSP is going to help birdie  removal.