Thanks. I’ll make a wild generalization that transceivers are generally designed for the receiver portion to be 50 Ω.
Anybody have an idea about SWL receivers? wunder K6WRU Walter Underwood CM87wj http://observer.wunderwood.org/ (my blog) > On May 25, 2022, at 10:05 AM, Wayne Burdick <n...@elecraft.com> wrote: > > All antenna-facing stages in our receivers are designed for a nominal 50 ohm > input. All of the preamp stages incorporate feedback to ensure a predictable, > constant input impedance. > > 73, > Wayne > N6KR > > >> On May 25, 2022, at 9:44 AM, John Oppenheimer <j...@kn5l.net> wrote: >> >> Hi Walter, >> >> Elecraft receivers, I'm familar with (K2,K3,KX[23], use "Feedback >> Amplifiers" for their Pre Amp. The Feedback Amplifiers are designed for >> nominal 50 ohm input impedance. Fifty ohm input impedance is somewhat >> import for operation of the receiver bandpass filter. >> >> I'll assume detector input impedance, preAmp bypass, is also nominal 50 >> ohm impedance. >> >> John KN5L >> >> On 5/25/22 11:05 AM, Walter Underwood wrote: >>> What is a typical input impedance for modern receivers, or specifically >>> Elecraft receivers? >>> >>> I’m asking because antenna tuners are a frequent question on an SWL group I >>> follow and I’m pretty sure that they are not needed for most situations. If >>> the receiver input impedance is not 50 Ω, that is a big data point. >>> >>> My belief is that receivers are generally medium or high impedance, >>> depending on whether the first RF preamp is bipolar or FET, but either way, >>> mostly voltage-oriented. >>> >>> And, yes, I know that antenna tuners can be a LPF or HPF, depending on >>> their configuration. >> ______________________________________________________________ >> 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 n...@elecraft.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 wun...@wunderwood.org ______________________________________________________________ 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
