Adding a little to these comments: I operate a lot of CW on traffic nets, and with props the way they are, often have to deal with pretty weak signals on 40m. The NR function works well to make an apparent improvement in the signal-to-noise ration to a significant and useful degree; however the leading edge of each character is somewhat attenuated, with the amount of attenuation decreasing over several dots worth for each character. During the space between characters and words the attenuation is "reset" so that it starts all over on the next character. The effect is to make the first few elements of each character hard to pick up, though later elements are nice and clear. Put simply, the NR gives a "mushy" effect to the code (at about 20-25 wpm). I suppose this is a function of the DSP "training" itself to find the best possible S/N ratio in a relatively short time. If this "training" could be remembered just a little longer so that it remained constant for a train of words, it would be much more useful. Haven't tried it at higher speeds since the nets all run at about the same speed.
Just my $.02! 73, Van W1WCG ----- Original Message ----- From: "WILLIS COOKE" <wrco...@flash.net> To: <elecraft@mailman.qth.net>; "Darwin, Keith" <keith.dar...@goodrich.com> Sent: Monday, February 02, 2009 11:01 AM Subject: Re: [Elecraft] K3 Narrow CW Filter >I have not found NR to be useful for CW reception. It distorts the signal >even on the lowest setting and to me makes the signal harder to copy than >without NR. I use 50 and 100 HZ DSP a lot and these narrow settings seem >to improve the signal to noise level a lot. > > I just finished a lot of operation as K3Y/5 where a number of operators > were having a competition to see how low they could set their power and > still make a sort of contact. It gave me a lot of practice in copying ESP > level signals with the other guy running well less than a watt. I have > the 8 pole 250 Hz filter, but I think the DSP filter is doing the heavy > lifting. > > So far, I have not found the NR to be useful for SSB or CW. > > Willis 'Cookie' Cooke > K5EWJ, K3 1025 > > > --- On Mon, 2/2/09, Darwin, Keith <keith.dar...@goodrich.com> wrote: > >> From: Darwin, Keith <keith.dar...@goodrich.com> >> Subject: Re: [Elecraft] K3 Narrow CW Filter >> To: elecraft@mailman.qth.net >> Date: Monday, February 2, 2009, 7:50 AM >> NR in the K3 is a tool that primarily turns the volume down. >> Well, in >> all fairness, it does so selectively, turning down the >> noise more than >> the signal, but it does result in a reduction in signal >> even though the >> S/N ratio gets better. I'm thinking at 100 hz, there >> is so little noise >> for NR to process that it is easier for the signal to get >> treated as >> noise and to be attenuated. >> >> You may find you get the rig to sound better if you quit >> using NR and >> adjust the AGC slope or threshold instead. Set the AGC >> threshold higher >> and reduce the ratio a bit. This will help to generate >> more of a ratio >> between the signal and background noise. >> >> ESE - nice call by the way ! >> >> 73 >> >> - Keith N1AS - >> - K3 711 - >> >> -----Original Message----- >> From: elecraft-boun...@mailman.qth.net >> [mailto:elecraft-boun...@mailman.qth.net] On Behalf Of John >> Huffman >> Sent: Monday, February 02, 2009 10:05 AM >> To: elecraft@mailman.qth.net >> Subject: [Elecraft] K3 Narrow CW Filter >> >> I'm getting used to my new K3, but have a question. >> >> My K3 has the 400hz 8-pole filter and the latest firmware. >> I've noticed >> that the difference between running the DSP filter at 100hz >> and 150hz is >> greatly increased volume at 150hz. With the NR on (F2-4) >> easy listening >> at 100hz will bow your ears out at 150hz. Is this just me? >> I run AF >> gain at 9 o'clock and RF gain at 12 o'clock. >> >> I have a second question. I liked to run my Orion on CW >> with the AF gain >> up, RF gain down, narrow filter and NR on. That way it >> listening to the >> other station was like listening to a code practice >> oscillator. On the >> K3 I still get background hiss with the noise reduction on. >> Are there >> better settings to use to get the sound I want with no >> background noise? >> >> Thanks in advance. >> >> 73 de K1ESE >> John >> >> ______________________________________________________________ >> Elecraft mailing list >> Home: http://mailman.qth.net/mailman/listinfo/elecraft >> Help: http://mailman.qth.net/mmfaq.htm >> Post: mailto:Elecraft@mailman.qth.net >> >> This list hosted by: http://www.qsl.net >> Please help support this email list: >> http://www.qsl.net/donate.html >> ______________________________________________________________ >> Elecraft mailing list >> Home: http://mailman.qth.net/mailman/listinfo/elecraft >> Help: http://mailman.qth.net/mmfaq.htm >> Post: mailto:Elecraft@mailman.qth.net >> >> This list hosted by: http://www.qsl.net >> Please help support this email list: >> http://www.qsl.net/donate.html > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:Elecraft@mailman.qth.net > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
