I use APF only as a last resort, Robert. It can sometimes help me dig out and record very weak 10m beacons under QRM from adjacent beacons, with CW filters on turbo, sometimes also using the manual notch filter to try to kill the worst QRM. It takes time to peak the desired signal precisely on the nose of the APF, using the fine tuning setting, the CWT function and watching audio levels with the audio recording software (Audacity in my case). Beacons transmit continuously so there is no mad rush to get it set up. For regular DX QSOs, it's not worth the bother in my opinion, but as I recall the APF facility was introduced in response to requests from 160m DXers desperate to glean the faintest sniff of RF from the ionosphere. It does indeed ring. There is probably a physics lecturer desperate to tell us that ringing is an inevitable consequence of the very tight filtering, plus artifacts from the digital processing I guess. Ringing gets worse with fast CW but beacons tend to send quite slowly.
73 Gary ZL2iFB > -----Original Message----- > From: elecraft-boun...@mailman.qth.net [mailto:elecraft- > boun...@mailman.qth.net] On Behalf Of Robert G Strickland > Sent: Saturday, 11 May 2013 11:46 a.m. > To: Elecraft > Subject: [Elecraft] K3 -Advice: how to configure APF for least ringing > > As a 98% cw operator, I've explored the various K3 weak signal features. > I tend to shy away from the APF because its ringing seems to my ears to be > counter productive. Any advice/experience on how to set up and use this > feature for best results? Thanks. > ...robert > -- > Robert G Strickland, PhD ABPH - KE2WY > rc...@verizon.net.usa > Syracuse, New York, USA > __________________________________________________________ > ____ > 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 -- This message has been scanned for viruses and dangerous content by MailScanner, and is believed to be clean. ______________________________________________________________ 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
