[Elecraft] KDSP2 - SSB Noise reduction

[Baker]

Yesterday I was in an 80m SSB net where one of the stations was really 
down in the noise, lots of QSB and background hash.

In an effort to copy him I first narrowed down the XFil B/W, that did 
not work so I tried the same with the DSP B/W, same result.
Finally I selected NR on the KDSP2 and the signal became much more 
readable.

Nothing strange about that you might say, but previously switching in 
the KDSP2 NR on my K2 had REDUCED the signal readability due to 
artifacts proceed by the process. In short I never used the NR on SSB, 
only using the DSP for notching hetrodynes.

I examined my settings and found that I still had SF2 selected (200Hz 
to 2.5kHz). I normally run the KDSP2 on SF1 ((LPASS F), and use the 
XFil to select the B/W. 

It would appear that a lot of the artifacts causing a loss of 
readability are located at the LF end of the audio spectrum, and 
filtering them out made a big difference.

Knowing this, I shall now play with the NR settings and see what can 
be achieved, always having some AF filtering selected.

I wonder if anyone else has had this experience ?

73

Stewart G3RXQ




-- The Baker's Home 
-- baker@nildram.co.uk on 10/01/2004 
=A0