[Elecraft] APF For K3

[Dale Parfitt]

 > When dealing with very weak signals in the absence of really strong QRM, 
I
> use the widest bandwidth possible for just that reason. At least 2.8 kHz 
> is
> typical for me and I almost never drop below 1 kHz. The more pink or
> white-ish the noise, the easier it is to hear a very weak CW signal down 
> in
> it.
>
> That's why I vastly prefer the notch filter to help my gray matter filter 
> in
> case a really strong signal appears in the bandpass.
>
> On stronger signals mixed in a lot of heavy QRM I'll crank in the 
> bandwidth
> so the desired signal is the only one I hear. Then I can pretend I'm
> listening to a code practice oscillator - it sure doesn't sound like a
> "radio", Hi
>
> Now that Wayne's implementing APF I'm curious to see how it sounds. I'm
> prepared to be astonished if it sounds any different than a decent active
> audio filter with some gain at the center frequency.
>
> Ron AC7AC
>
Hi Ron,
A lot of my activity is on 1296MHz EME where the background noise is 
extremely consistant. I found the APF on the IC-7700 to be useless, but 
interestingly the audio peak function on my Alpha Delta   VRC (Variable 
Response Console) consistantly pulls weak CW signals out that the narrow 
roofing and/or DSP filters do not.
Visitors to my station have noticed the same effect- and have gone searching 
for  a VRC for their EME station. Reports here on the reflector that  it is 
possible for an APF to function very well are encouraging- so I  too look 
forward to its implementation.

Dale W4OP