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History of Single Sideband (SSB) by Len Anderson
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From: lenover21@aol.com (Len Over 21)
Newsgroups: rec.radio.amateur.policy
Date: 02 Jul 2001 23:06:36 GMT
References: <cuvyxnansvbet.gfum6np.pminews@ca.news.verio.net>.
Organization: AOL http://www.aol.com
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Subject: Re: Pendulum reverses
Message-ID: <20010702190636.07922.00000548@nso-cr.aol.com>.
Xref: newscene.com rec.radio.amateur.policy:199954
In article <cuvyxnansvbet.gfum6np.pminews@ca.news.verio.net>.,
"Phil Kane"
<Phil.Kane@nospam.spam>. writes:
On 02 Jul 2001 05:38:49 GMT, Len Over 21 wrote:
That's a nice little homily that's been roaming
around the OF circuit for quite a while. It must be
popular since all four were hams (Godfrey the biggest
ham of all). It may even be true, given the
under-the-table contract awards which happened in the
late 1940s to the middle 1950s.
If you want to reach out beyond the restricted history
of radio seen through amateur-only publications,
FYI my info came from non-ham pubs about SAC
communications history and from 3 years assignment to
the 22nd Comm Squadron (USAF-SAC) who RAN that equipment
("Short Order") in 24/7 operation. Half my time at
Offutt AFB (HQ-SAC) and the other half at March AFB
(Alternate SAC
HQ) as command post system test and compliance officer,
with plenty of time to shmooze with the SAC comms
old-timers who knew the history of SAC comms.
Phil, I don't doubt your personal military experience or
that the Strategic Air Command (SAC) did successful
trials of single-channel SSB military radios. I am
doubting some of the old-timers'
schmooze stories along with the exaggerated (or not)
importance of the mode for whatever reason. Let's look
at the chronology of SSB in general again:
1. SSB is first used on landline "carrier" equipment
around 1915 for frequency-division multiplexing of up to
four telephone circuits on one wire pair (important for
long-distance cost reduction).
2. SSB over AM superiority on radio is theoretically
analyzed and published 1922 and 1923, Proceedings of
I.R.E.
3. First radio trial of SSB begins 1928 on VLF. Problem
is one of getting adequate vacuum tube power
amplification but modulation method works fine. Power
vacuum tube inadequacies plague all radio modulation
modes then.
4. Four voice-channel SSB HF link established between
Netherlands and Netherlands Antilles in 1934. This
proves it can be done and remain in service 24/7.
5. Western Electric develops, makes, uses a four voice-
channel SSB transmitter by 1938 (I operated and helped
repair one of those still in use in 1953). That model
was bought for US Army and US Navy military HF
fixed-station communications that same year. They will
develop a "modern" version, the LD-T2, beginning just
after WW2 and that commercial model will also be bought
by the Army and USN before 1951.
6. All this while the landline telephone long-distance
network is served by frequency-multiplexed "carrier"
equipment utilizing SSB techniques. Transmission is over
wire pairs, coaxial cable, or microwave radio relay. WE
had their foot in that market door, Collins Radio tried
but could not get very far into it despite a good record
at radio communications equipment. ["mechanical" Collins
filters were originally made for landline "carrier"
applications according to an old-time Collins-Rockwell
applications engineers and the old spec sheets show the
available frequency spacing to fit that]
Up to around 1950 there had been little work done on
single- channel SSB for any radio service due to
frequency stability. Fixed-station HF radios needed a
"pilot carrier" to stay locked on a received
transmission. USAF Rome Air Development Center and other
groups established a need of getting within plus-minus
300 cycles of the exact carrier frequency for voice
intelligibility. This narrow tolerance seemed at odds
for multi- frequency frequency selection by relatively
untrained-in-radio
personnel so several companies started developing the
first "frequency synthesizers" and working on stability
control of quartz crystal oscillators as well as analog
VFOs that would suit harsh environments. RCA Corporation
did their thing on that, so did Stromberg-Carlson and
National Radio Co. Collins Radio was not alone in that
area.
None of the above was secret in any way the whole
time. SSB was already known, quantified over a long
period before the west entered the Cold War in 1948. The
information did not always make it to amateur radio
oriented publications because it was not about or for
amateur radio (in the consideration of the publishers).
The exception was the immediate post-WW2 period and some
carefully steered PR by Collins Radio. Collins was
looking for a reputation. Collins already had a
reputation as a good radio maker, solid and dependable,
but not all that innovative.
Cut to the "fab four" of LeMay, Collins, Goldwater,
Godfrey. All radio amateurs whether early or late in
life. LeMay now SAC chief despite some shaky and
controversial late-WW2 leadership (fire-bomb raids on
Tokyo). Godfrey a stage ham as well as a radio ham who
had a popular daily radio show.
Goldwater then a rather junior politician, a "comer" who
had yet to develop his reputation or political base that
would be later. Collins wanted his company to prosper
but faced some stiff competition in the
now-clearly-expanding radio market of the immediate
post-WW2 period.
Put all of those above facts together with the
reputation that Collins Radio earned a decade later,
spread the story, and it looks like Collins "invented
SSB" or at least "pioneered SSB" when what they really
did was come up with a stable single-channel SSB radio.
RCA did the same but RCA had a somewhat negative
reputation among US hams...nor did they have any
engaging personalities such
as Godfrey who could pump up the SAC.
They lacked only Jimmy Stewart for a visual impact on
publicizing SAC as a reserve USAF General unabashedly
promoting a needed service arm during the Cold War.
Gen. LeMay got his ham license relatively late in the
game and the others were long-term hams, but their roles
in this situation had absolutely nothing to do with ham
radio or their existence as hams.
More to the late-night "good ol boy" get-togethers in
Cedar Rapids/Omaha and DC.
"Insider" stories exist in other areas but are not as
popular as this one in amateur radio circles. The
electronics industry of a half century ago was still
growing (Collins Radio a part of that but not that big a
part) and, not coincidentally, started facing a lot of
contract-award controls around 1950. Those government
controls would become more severe until stabilizing
around 1970. "Good old boy-ism" wasn't quite the same
anymore, as if it really was to begin with.
Repeated stories sometimes become folklore, close to
truth but not quite there. In conjunction with other
industry stories and "inside information," I won't buy
this amateur SSB folklore at face value. That doesn't
tarnish the good reputation of Rockwell-Collins a bit.
The story tellers' rep is another matter.
LHA
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