Thanks again Lyle, I believe I now have the proper prospective (looking at the block diagram of the K3 helped out too). So far in my limited operation of K3 #338, anytime I've tried to dig out a weaker CW signal next to a stronger one, the DSP filter has worked just fine. And I found when it was a little too close I was able to shift the filter away from the offending signal enough to hear the desired one very comfortably. Of course, these were in non contest and non-aggressive situations.
I saw a post the other day about the notch filter. I have used it a couple of times in the old novice portion of 40m (where I hang out with the QRS crowd). When some of the BC stations start up, I was able to notch out that carrier just fine and turn an irritating listening situation into something very comfortable. Very nice work. Thanks again Lyle (hope I didn't bore too many on the list). 73, Dave W8FGU > > Hello Dave! > > > So if I read this right (bear with me, I'm learning), in keeping strong > > signals out of its passband, it will keep the hardware AGC from > activating > > to eliminate "pumping"... > > Correct. > > > But, in the same scenario, if I had a 2.7khz filter and a 200hz filter > with > > no strong signals, just band noise (or maybe static crash type QRN), the > DSP > > filter would act the same and my desired signal would come through the > same > > way regardless of which roofing filter I used... > > Also correct. The key is if signals stronger than the desired signal > are in the roofing filter passband, and are also strong enough to > activate the hardware AGC. > > > And if you would permit me one more scenario. In the case of strong > static > > crash type QRN, in my case, either the noise blanker or noise reduction > > would be able to handle the really heavy stuff. I know the hardware > noise > > blanker is set in front of the roofing filters and well ahead of the > DSP, > > therefore protecting it. I guess that statement is more of a question > than a > > statement. > > We have pulse-suppressing AGC in addition to DSP and IF blankers. Won't > kill all the noise types, but makes a very effective arsenal against > noise. Narrow roofing filters can help in some cases here, too. > > In the end, you may not often need narrow roofing filters in your > particular station's interference environment, but when you need 'em, > you need 'em :-) > > 73, > > Lyle KK7P _______________________________________________ Elecraft mailing list Post to: [email protected] 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
