Wayne, My intuition says that the problem is not in the filter algorithm. Could be that the APF just not engages in 4.22? Could be that instead of APF it is still does Dual PB or something? Can you try to listen to the weak CW with 2 rigs - one with 4.17 and one with 4.22? When I engage 4.22 APF I hear high pitch noise at frequency range close to the CW pitch, which makes hearing CW signal very hard. The 4.17 (and 4.18) did not have this. I have 400Hz 8-pole and 250 Hz 8-pole filters, I tried with both - same problem.
73, Igor, N1YX -----Original Message----- From: elecraft-boun...@mailman.qth.net [mailto:elecraft-boun...@mailman.qth.net] On Behalf Of Wayne Burdick Sent: Saturday, November 20, 2010 3:44 PM To: elecraft@mailman.qth.net Subject: [Elecraft] Final K3 APF Lab Test Results We just did a *very* accurate sweep of the APF passband from the original (4.17) and new (4.22) beta releases. Lyle has the data in spreadsheet form and will send it out on request. It's too big to attach to a reflector posting. Bottom line: There is no difference between the two. This is not surprising, since we did not change the filter algorithm. Any difference must be attributed to noise and signal conditions, filter bandwidth settings, or APF tuning vs. actual signal pitch. This is the nature of APF; it is most effective under specific conditions. Try turning it on, and if it doesn't help, leave it off. 73, Wayne N6KR ---- http://www.elecraft.com On Nov 20, 2010, at 12:16 PM, John Seney <john.se...@gmail.com> wrote: > Hi All: > > I have the same experience as Igor. There is an APF sweet spot that either moved or > disappeared. > > Would it be helpful if there was a GUI that let us save, load, share, and see all of > the various K3 parameter settings that we are adjusting? > > On Nov 17, 2010, at 11:53 PM, Igor Kosvin wrote: > >> Sure, you are right, but you would not deny that using same set of >> parameters (NR/NB, WIDTH, PITCH, RF, etc) the APF circa 4.17 and 4.22 should >> give very similar results since the code of APF remains the same. After >> playing few days with 4.22 I find myself having to turn off APF to better >> receive weak CW stations. I don't have explanation for this. With APF on I >> find it difficult to distinguish dits and dahs of weak signals. With 4.17 it >> was much better for me. That should be apples-to apples comparison, I think. >> I don't claim to be expert though, listening is very subjective IMHO. >> >> Regards, >> >> Igor, N1YX > > > 73, > > John Seney > ARS WD1V (fn42gw) > 603 785-2413 > > > ______________________________________________________________ > 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
