John, I would not select a radio on the input impedance of the microphone input! It is not critical at all - should be at least 10 times the microphone impedance.
Pro-Audio from as far back as the antique Western Electric unbalanced systems of the 40s tend to be in the range of 1 k to 10 k. Mostly depends on what the designer wants to emphasize. Lower would tend to reduce noise pick-up. Higher would tend to load the mic less thus improving S/N. Probably neither value is significant. George AI4VZ -----Original Message----- Was there a compelling reason for having different termination values, 10k vs. 1k, between transceiver model lines? ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
