Chris,
For reasons of providing a sharper audio filter, I believe it is a
toss-up between the KAF2 and the KDSP2 - both will do the job. The DSP
offers more flexibility in the filter width and can create a really
steep sided filter. As far as noise reduction, the KDSP2 wins hands
down, the KAF2 has none, and yes, the KNB2 does not work on atmospheric
noise - it does a good job on impulse type noise sources, like gasoline
engine ignition noise.
That said, my ears tire of hearing the DSP after long periods. Maybe it
is just too clean, or perhaps my ears like the more rounded filter
shapes, but that is my personal subjective assessment. I have an
external DSP in my AMQRP micro908 that I can press into service when the
occasion arises, and I have my K2 fitted with the KAF2. In fact, I
rarely use the KAF2 because the K2 IF filters are good enough most of
the time.
As it has been mentioned, perhaps the best solution to your noise
situation is to use a separate receiving antenna such as a rotating loop
(assuming something like a beverage is not feasible).
73,
Don W3FPR
Chris Kantarjiev wrote:
Does this combination make sense? I operate 100% CW. These days, I seem
to be chasing a lot of very weak signals with questionable readability.
My vertical isn't the quietest of antennas (they never are) and my
neighborhood has a fair amount of QRM on 40m during "real people hours".
For example, this morning I was trying to get KH2/JR4GPA. Copying his
sign was very tough, but I finally got it and confirmed it. I called
a couple of times but realized that I wouldn't recognize my call even
if he returned it! Just on the egde of ESP.
So ... would AF or DSP help me in this situation? The noise blanker
doesn't seem to do much good for the noise sources my neighbors provide.
Thanks!
73 de chris K6DBG
_______________________________________________
Elecraft mailing list
Post to: Elecraft@mailman.qth.net
You must be a subscriber to post to the list.
Subscriber Info (Addr. Change, sub, unsub etc.):
http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/subscribers.htm
Elecraft web page: http://www.elecraft.com
