"Stinger" wrote in message
news
Thanks for that insight, Telamon.

I read in the manual for one of my radios that "advanced" hams tend to
use
USB, but having listened to some of them, I doubted that theory.

Yours makes much more sense

-- Stinger


It goes back to the first generation SSB transmitters which often
generated SSB around 9 Mc. Heterodyning the frequency lower inverts the
frequencies, which turned the USB at 9 Mc to LSB at 7 or 3 Mc.
Heterodyning up doesn't change the frequency relationship, and USB
remains USB.

Frank Dresser