[Elecraft] K2 Mods for KPA100

[Lyle Johnson]

>> Yes, they share the same parameters.
>
> Thank you for explaining that.  Is that because the DSP can't find out 
> the mode?  So you can optimize the DSP for CW or SSB?  Or am I confused?

You are not confused -- at least not on this point :-)

The denoiser is common to both the CW and SSB audio paths.  Since it is 
mostly tailored to your audio preferences, it remains as you set it for 
both modes.  The primary difference you will discover in using it for 
SSB or CW is that CW signals sound louder through the denoiser than 
voice signals.  This is because of a factor we call "correlation" which 
is how the DSP decides if a voltage is part of noise (random) or part of 
a desired signal (CW or voice, less random).  Because CW is more highly 
correlated (less random than voice), it passes through the denoiser more 
easily.  This effect is compensated for in the Sn and Cn gain menus, 
which would normally be set to make the apparent audio level the same 
for moderately strong signals of both types.

The denoiser is most effective with CW when the filters are wide.  As 
the filters get narrower and narrower, the denoiser is less and less 
useful, in part because the filters "color" the noise and make it seem 
more like a signal.  The extreme example of this is ringing.

Enjoy!

Lyle KK7P