Farhan alerted us to a very interesting presentation on the history of single sideband: It was in episode 81 of Bob Heil's "Ham Nation" show. It starts at minute 22:
https://www.youtube.com/watch?v=xSF0WBdK1IQ&feature=youtu.be
Two things really caught my attention:
-- Note how OM Carson, way back in 1915, had figured out how to get rid of the carrier, but needed some way of eliminating the unnecessary sideband. He did it by using his antenna tuner as a filter. FB OM!
-- In the early days of SSB, when it was an exciting new technology, hams had regular "sideband dinners." At these events an award was presented. Kind of like an Oscar or an Emmy I guess. The award was the "Sideband Suzy" (see above). Kind of a classic figure... but half of Suzy was missing!
8000km opening at 40 MHz from South Africa to Australia - 16th Apr 2024
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As we move further into April, the F2 layer propagation in the northern
hemisphere is getting worse on the higher HF bands but in contrast, things
are im...
2 hours ago
I thought the antenna was narrow enough in early SSB experiments to eliminate the unwanted sideband. It was way down in frequency, not really a surprise since everything was on low frequencies at the time.
ReplyDeleteI seem to recall that the ham use of ssb before WWII, the few of them, used filters down around 30KHz, not so great for image rejection. But in retrospect not so far from the 50KHz used in some Drake receivers, or the 85KHz IF in the LF Command Set receiver, desired because of the selectivity.
Michael