I'll check the APF in 4.16 after work and see if it's any different. Barry N1EU
On Thu, Jan 27, 2011 at 7:58 PM, Steve Ellington [via Elecraft] < ml-node+5967599-613958550-2...@n2.nabble.com<ml-node%2b5967599-613958550-2...@n2.nabble.com> > wrote: > FW pre-beta 4.16 release was actually the first to have APF, not 4.17. > Here's an interesting comment made shortly APF was finally released to the > public. > http://elecraft.365791.n2.nabble.com/K3-APF-td5735159.html#a5736718<http://elecraft.365791.n2.nabble.com/K3-APF-td5735159.html?by-user=t#a5736718> > > > > Steve > N4LQ > ----- Original Message ----- > From: "Arie Kleingeld PA3A" <[hidden > email]<http://user/SendEmail.jtp?type=node&node=5967599&i=0>> > > To: <[hidden email] <http://user/SendEmail.jtp?type=node&node=5967599&i=1>> > > Sent: Thursday, January 27, 2011 6:44 AM > Subject: [Elecraft] APF measurements: FW 4.17 better results by 2 dB > > > > Hello all, > > > > Did some measurements on the different frimware versions. This time not > > a BW-plot but I measured S+N/N ratio's. > > > > > > I have no lab equipment but I have a K3 with dBV measurements, XG2 and > > the stepped attenuator from elecraft. > > I measured the difference of the K3 dBV-reading in signal off (=N) and > > signal on (=S+N) > > AGC off, mode CW, 400Hz BW and 400Hz Roofing. > > RX gain of the K3 has been calibrated with XG2 and the K3 utility. > > > > > > This is what I found. > > > > _FW 4.25 and 4.21 (both give the same measurement values):_ > > At MDS level (stepped att on 20dB to reach this level) > > normal 400 Hz BW: S+N/N = 3dB (as expected, hi) > > 400 Hz BW + dual PB: S+N/N = 10 dB > > > > Now signal level 6dB under MDS (26dB att instead of 20dB): > > normal 400 Hz BW: S+N/N = 0.5 dB > > 400 Hz BW + dual PB: S+N/N = 4 dB > > > > > > _FW 4.17_ > > At MDS level (stepped att on 20dB) > > normal 400 Hz BW: S+N/N = 3dB (as expected) > > 400 Hz BW + dual PB: S+N/N = 12 dB (THIS is 2 dB BETTER) > > > > Now signal level 6dB under MDS: > > normal 400 Hz BW: S+N/N = 0.5 dB > > 400 Hz BW + dual PB: S+N/N = 6 dB (THIS is 2dB BETTER) > > > > > > There are probably people that can measure this far more better than I > > did with better equipment. > > But this is what I can come up with here. > > > > 73, > > Arie PA3A > > > > > > > > Op 27-1-2011 0:52, Barry N1EU schreef: > >> Forget it - full stop! > >> > >> I just ran a spectral analysis of the current firmware versus the very > >> first > >> APF implementation (mcu 4.17 dsp 2.65) from 11/3/10 AND THE PLOTS ARE > >> ABSOLUTELY CONGRUOUS! The APF implementation hasn't changed a bit (or a > > >> byte). > >> > >> Have a look: http://n1eu.com/k3apf.gif > >> > >> magenta and green plots are taken with width = 200hz > >> aqua and yellow plots are taken with width = 100hz > >> > >> Barry N1EU > > ______________________________________________________________ > > Elecraft mailing list > > Home: http://mailman.qth.net/mailman/listinfo/elecraft > > Help: http://mailman.qth.net/mmfaq.htm > > Post: mailto:[hidden > > email]<http://user/SendEmail.jtp?type=node&node=5967599&i=2> > > > > 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:[hidden > email]<http://user/SendEmail.jtp?type=node&node=5967599&i=3> > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > > > ------------------------------ > If you reply to this email, your message will be added to the discussion > below: > http://elecraft.365791.n2.nabble.com/APF-tp5963894p5967599.html > To unsubscribe from APF, click > here<http://elecraft.365791.n2.nabble.com/template/NamlServlet.jtp?macro=unsubscribe_by_code&node=5963894&code=YmFycnkubjFldUBnbWFpbC5jb218NTk2Mzg5NHwtMTUyMTIxNjYw>. > > ______________________________________________________________ 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