[Elecraft] Back to the KAF2

[Dale Boresz]

Hello Stewart,

I was not implying that the noise was coming *from* the KDSP2. It is 
there in spite of the KDSP2, unlike with the KAF2, which has a passive 
low-pass filter which significantly reduces it. The noise is from the 
base K2, not the KDSP2. However, it's really only noticeable when using 
high quality headphones intended for listening to music, or when using a 
good external speaker. If one mostly uses the internal K2 speaker, I 
doubt very much that the hiss would be noticeable. It's easily seen on 
Spectrogram, and it's also very easy to see the effectiveness of the 
passive elliptic filter with Spectrogram by simply looking at the noise 
floor above 2KHz with the KAF2's bypass switch alternated between the 
"IN" and "OUT" positions.

I guess everyone has certain aural sensitivities, and mine is 
noise/hiss. I find it really distracting. On the other hand, the 
artifacts of the DSP don't particularly bother me, and I find the KDSP2 
to be very effective both with CW and SSB, although being primarily a CW 
op, 90% of my usage is with that mode. Still, I've found it to be very 
helpful on SSB, when trying to wrestle with the noise on the 60 meter band.

73,
Dale / wa8sra

Baker wrote:

>I have not noticed any significant increase in hiss with the KDSP2, 
>however I find the nr artifacts on SSB so annoying I only use the 
>notch filter.
>
>
>  
>