I find that placing a low pass filter in the audio really softens things up and fixes the issues that you're talking about here.
~Brett On Sun, 2009-08-09 at 09:04 -0400, Steve Ellington wrote: > Normally I would agree with all these suggestions that help us hear CW under > noisy conditions however I'm convinced that there is simply nothing there to > hear. Let's say we are listening to a weak CW signal on a noisy band and the > station sends the word T H E. What I hear is T S E because just at the wrong > instant, the noise "blipped the dit". (new techy term). I'm not talking > about huge QRN peaks of S9+30 or anything....Just a bit of atmospheric noise > that's producing some S meter fluctuation and just enough noise to be > annoying to listen to through a narrow CW filter but almost soothing when > heard through a wide SSB filter. > Listening to the same noise on the Jupiter is much less grating to the ears > even when using the 150Hz filter setting. BTW: Edwin, who originally posted > this question, tells me that his friend also has a Jupiter and although the > receiver isn't quiet as good, it handles that type of noise aspect better. > What's the deal with Jupiters? You can't even turn the AGC off! > Typically I blame AGC for such things but I can turn AGC off and still get > that blipping effect. The worst receiver I ever saw for this phenomena was > the TS-570. That thing would blip out entire letters as if it were punching > holes in the transmitted text. Nice little rig but not for copying CW in > noise! > I believe I'll play around with some audio software and try to see what I'm > hearing or what I'm not hearing. It could be some kind of mental weakness! > > Steve > N4LQ > [email protected] > ----- Original Message ----- > From: "Brett Howard" <[email protected]> > To: <[email protected]> > Cc: "'Steve Ellington'" <[email protected]>; "'Edwin Johnson'" > <[email protected]>; <[email protected]> > Sent: Sunday, August 09, 2009 1:35 AM > Subject: Re: [Elecraft] K3 Filter Ring with Noise? > > > > I'd never had a rig capable of going lower than 500Hz till I got the K3 > > and really found myself quite annoyed at times when the noise was high > > and I really necked the filter down. Its taken me time to figure all > > these things out but Joe really has some great tips here and has done an > > excellent job explaining why these things work. I also find that use of > > a lower FC makes the noise sit a little better with me as the noise is > > more subdued and not as piercing. > > > > One thing to try is to turn the bandwidth down to around 200Hz and find > > a quiet spot on the band then adjust your pitch up and down and listen > > to the band noise in a few places to see what you prefer based on the > > noise rather than the pitch. Then see if you can live w/ that pitch. > > > > I liked Joe's comment about it being spaced over more bandwidth. Thats > > an interesting thought but based on the whole logarithmic scaling stuff > > it does make sense. > > > > I find the dualPB filter is nice but I kinda wish I could adjust the > > size of my focus filter as well as the outer skirts. I'd even be ok if > > it was just a menu setting for the size of my focus filter. That would > > be something I'd be sticking on a PF button and I'd then use the dualPB > > more often. > > > > ~Brett > > > > On Sat, 2009-08-08 at 23:42 -0400, Joe Subich, W4TV wrote: > >> > >> > You did a wonderful job explaining exactly what I've noticed. > >> > To me, it seems as if the noise mixes or blends with the cw > >> > and at times blips out cw characters. This only happens when > >> > signals are weak and the band is noisy. > >> > >> What you are describing is not true filter 'ringing' but the > >> effect of band limited noise. Even though the noise is fairly > >> "random" it is confined in a narrow range and is close to the > >> desired signal. > >> > >> Keeping the filter wider may be somewhat counterintuitive in > >> noisy conditions but it helps in a couple ways ... first it > >> spreads the noise power out and allows the desired signal to > >> appear somewhat stronger than the "random" noise. Second if > >> you use a lower center frequency the noise is spread over a > >> wider percentage bandwidth and a larger portion of the noise > >> is 'far enough' away from the desired signal to allow the > >> ear-brain DSP system to work more effectively. > >> > >> > I've tried all the EQ settings, NR (which helps) and AGC > >> > settings to no avail. I don't consider this "ringing" since > >> > that's not what I'm hearing. > >> > >> Try a lower FC and slightly wider filters. Also give the > >> Dual PB filter a try. > >> > >> 73, > >> > >> ... Joe, W4TV > >> > >> > >> > >> > -----Original Message----- > >> > From: [email protected] > >> > [mailto:[email protected]] On Behalf Of Steve Ellington > >> > Sent: Saturday, August 08, 2009 9:32 PM > >> > To: Edwin Johnson; [email protected] > >> > Subject: Re: [Elecraft] K3 Filter Ring with Noise? > >> > > >> > > >> > Edwin > >> > You did a wonderful job explaining exactly what I've noticed. > >> > To me, it > >> > seems as if the noise mixes or blends with the cw and at > >> > times blips out cw > >> > characters. This only happens when signals are weak and the > >> > band is noisy. I > >> > recently came across an older TenTec Jupiter which has very > >> > wide skirts and > >> > virtually no roofing filter (15kHz). The same noise has no > >> > effect on it. I > >> > have done dozens of A/B test and the Jupiter always comes out > >> > the winner > >> > until someone with an S9+30 signal gets within the roofing filter's > >> > bandpass, like 6kHz away, and pumps the hardware AGC > >> > violently. Then it's > >> > all over and I either switch back to the K3 and suffer poor > >> > copy or just > >> > QRT. > >> > I've tried all the EQ settings, NR (which helps) and AGC > >> > settings to no > >> > avail. I don't consider this "ringing" since that's not what > >> > I'm hearing. > >> > > >> > Steve > >> > N4LQ > >> > [email protected] > >> > ----- Original Message ----- > >> > From: "Edwin Johnson" <[email protected]> > >> > To: <[email protected]> > >> > Sent: Saturday, August 08, 2009 3:34 PM > >> > Subject: [Elecraft] K3 Filter Ring with Noise? > >> > > >> > > >> > > I've had my K3, which I assembled, about a month, outfitted with > >> > > 13kHz, > >> > > 6kHz, > >> > > 2.8kHz, and 400Hz filters. Thus far I've been exceptionally > >> > pleased with > >> > > all > >> > > aspects of the rig. I've read with interest the audio > >> > discussions of this > >> > > group. There is one area in which I'm not totally > >> > satisfied, but this may > >> > > be > >> > > due, partially, with my expectations of the rig. > >> > > > >> > > When using CW on noisy bands, meaning the sort of > >> > atmospheric noise we > >> > > often > >> > > are having now (NOT static crashes from storms), there > >> > appears to be an > >> > > audio > >> > > product as the bandwidth is narrowed which is annoying to > >> > my ears, which > >> > > occurs both in speakers and phones. This is basically like > >> > a ringing of > >> > > the > >> > > filters and especially evident as the passband is narrowed > >> > to 50-150Hz. > >> > > This > >> > > phenomenon is not a problem in quiet conditions nor if the > >> > station is > >> > > especially strong, but can overpower a very weak station. > >> > (I'm using a > >> > > pitch > >> > > of 600Hz for CW.) > >> > > > >> > > (I've tried eliminating the 400Hz filter to make certain > >> > there isn't a > >> > > problem there, and all is well with that filter, apparently.) > >> > > > >> > > I've been reducing RF gain and sometimes widening the > >> > passband to help > >> > > aleviate the problem, as well as using the NR. I've also > >> > modified the > >> > > RX equalizer from flat to settings of: #1=0, #2=3, #3=3, > >> > #4=-1, #5=-4, > >> > > #6=-5, #7=-8, #8=-10. Admittedly, part of these settings accomodate > >> > > SSB to give, what I hear, as a very pleasant sound for that > >> > mode. The > >> > > primary ranges of this noise are affected mostly by filters > >> > #4 and #5. > >> > > > >> > > If the RX equalizer settings remain flat, hence 0, the > >> > sound is even > >> > > more annoying. But remember this is really only in noisy > >> > conditions, > >> > > so my hypothesis is that the chaotic sounds in the noise > >> > are mixing to > >> > > produce what sounds like a ringing of the filters. (So not > >> > necessarily > >> > > the filters actually ringing, as we think of it.) But this makes > >> > > working very weak signals very difficult without widening > >> > the passband > >> > > quite a bit. > >> > > > >> > > So, guess I would like to hear comments regarding this, as well as > >> > > settings > >> > > and techniques people use to combat this phenomenon. > >> > > > >> > > 73 ...Edwin, KD5ZLB > >> > > ____________________________________________________________ > >> > > "Once you have flown, you will walk the earth with your eyes turned > >> > > skyward, for there you have been, there you long to > >> > return."-da Vinci > >> > > http://bellsouthpwp2.net/e/d/edwinljohnson > >> > > ______________________________________________________________ > >> > > Elecraft mailing list > >> > > Home: http://mailman.qth.net/mailman/listinfo/elecraft > >> > > Help: http://mailman.qth.net/mmfaq.htm > >> > > Post: mailto:[email protected] > >> > > > >> > > 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:[email protected] > >> > > >> > 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:[email protected] > >> > >> 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:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
