Like many developments in "radio", Amateurs led the way with some Hams tinkering with SSSC (single sideband suppressed carrier) long before WWII. (One reference I've seen reports on-air Amateur experiments in 1933.)
Also, like much of "radio technology" the basics were understood long before that. In the case of SSSC the understanding appears to go back to the first detailed analysis of amplitude-modulated signals about 1915. And, like so many things, the understanding preceded the technology needed to make it practical. Hams, not being necessarily practical folks, pursued its use on the bands well before it was adopted for general commercial and military use. I think Villard at the Stanford University Amateur Radio club is credited (blamed?) for launching the Amateur SSB revolution on 75 meters about 1947 that brought Amateur use of SSB into the mainstream. It's likely the wall-to-wall heterodynes on the 'phone' bands caused by the huge increase in Hams on the air in the 1950's were a powerful inducement. Imagine a dozen, strong key-down CW carriers, all within 2 kHz of each, other producing a howl of multiple heterodynes on top of several weaker phone signals and you have an idea of what a typical "phone" band sounded like in the busy evening hours back then. Multiple notch filters were seldom enough to copy anything out of the cacophony. At that time SSB's general use required the development of adequately-stable receivers and transmitters. I recall reading several engineering journals in the 1950's reporting that they doubted sufficiently stable oscillators would *ever* be developed so the signals could be received by non-technical operators in the military and commercial services. That changed very quickly. My point is that Hams evolved their own "standards" for whatever reason before SSB was in general use by other services, so it is the other services who failed to follow the established "standards" on the Ham bands, not the other way around. But, then again, there's no more reason for commercial or military users to follow what Hams do than there is for Hams to follow what the commercial and military users do. Indeed, since a large part of Amateur radio is experimenting and try out things just because they interest someone, there's a lot of excellent reasons not to follow military and commercial standards. Granted, failing to follow commercial practice drives the pure "operators" a bit nuts because they can't buy any old "plug-'n-play" rig designed for commercial or military work and do what other Hams are doing. But *not* copying what the other services are doing is the point of Amateur radio for many. It's why Villard launched the SSB "revolution" in the first place. Ron AC7AC _______________________________________________ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
