I am definitely not an expert on this, however, all of the early military manuals on the applications of SSB explained how "the only practical way of removing the unwanted sideband is with a 100 kc [old terminology for kHz] crystal filter, as the other filtering techniques are inadequate."
You can even find some of these old Collins "mechanical" filters, in this range but usually up in the range of 455 kHz. I think you will find that the early ham SSB rigs used some form of these intermediate frequency mixers/filters and thus throwing in another possibility of why the sidebands are inverted. Navships 93271 "Fundamentals of Single Sideband" page 2-1 has a block diagram of a SSB receiver with a 250 kc balanced modulator (mixer-filter-etc.), 2.7 - 3.7 vfo and a 4 mhz and 11 mhz switched xtal oscillator (for 7 and 14 mhz output respectively.) That would satisfy the "math" and the present convention. Rich KE0X _______________________________________________ Elecraft mailing list Post to: [email protected] http://mailman.qth.net/mailman/listinfo/elecraft You must subscribe to post. Subscriber Info (Addr. Change, Unsub etc): http://mailman.qth.net/subscribers.htm Elecraft page: http://www.elecraft.com
