Hi Ben, Others with more knowledge may chime in, but here is what I know:
The crossover frequencies you can find in the K3S schematic file. Here is a link to it: https://ftp.elecraft.com/K3S/Manuals%20Downloads/E740323%20K3s%20Schematic%20Files.pdf It is the first page in the "options" segment. You can search for "KBPF3A" to find it (the file is *big*). I have not been able to find any real specifications for it. The installation manual has no specs. I also don't know if either ARRL or Sherwood has collected any data outside of the regular ham bands. In principle the K3(S) equipped with this filter should have nearly identical sensitivity anywhere from 0.1 to 30MHz. Note: the KBPF3 version has L1 installed which limits the low end to 0.5MHz. If you have an unmodified early K3 and want to use it below 0.5MHz you need to add add a bypass capacitor as described in the installation manual. Without that the bottom end is very noisy from power supply noise. I know many people are fascinated by Non-Directional-Beacons (NDBs) which are generally in that low frequency range. I have it in my K3S and find plenty of sensitivity anywhere in the range supported (0.1-29.7MHz). I don't do much SWLing anymore since the number of English language SW transmitters have dwindled over the past 10 years. It's all Internet radio these days. Are you sure you have good antennas for the bands where you think sensitivity is low? I certainly have no problem using a 102' G5RV anywhere from 0.5 to 29.7MHz for reception. I leave the tuner in bypass. Knut - AB2TC w4sc-2 wrote > Looking for details of switch over frequencies and expected performance of > the KBPF3A in its various bands, > > There is improvement in the BCB and below 500KHz with the KBPF3A enabled, > however the other SW BCB bands I have tried are lacking. > > Has anyone measured the performance of the KBPF3A? > > Ben W4SC > > Sent from Mail for Windows 10 > > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto: > Elecraft@.qth > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > Message delivered to > lists+1215531472858-365791@.nabble -- Sent from: http://elecraft.365791.n2.nabble.com/ ______________________________________________________________ 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 Message delivered to arch...@mail-archive.com
