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Amateur Radio and the Rise of SSB the Hams Who Were First to Get on the Air with Single Sideband Created a Revolution in Amateur Radio

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Amateur Radio and the Rise of SSB the Hams Who Were First to Get on the Air with Single Sideband Created a Revolution in Amateur Radio By Gil McElroy, VE3PKD Amateur Radio and the Rise of SSB The hams who were first to get on the air with single sideband created a revolution in Amateur Radio. Along the way, sideband would even affect the course of the Cold War. he cover of the January 1948 issue as the move from spark to CW had been of QST was, well, different. An in the 1920s. Sideband’s impact has been Toscilloscope was pictured, and enormous and the changes it has created though it was a piece of equipment few in Amateur Radio far-reaching. It is ubiq- hams owned or were familiar with at the uitous today, a standard feature on virtu- time, that wasn’t what made the cover ally every commercially produced piece so unusual. Rather, it was the strange- of amateur equipment. And it isn’t sim- looking modulated wave envelope dis- ply useful for voice communication; side- played on its CRT screen. Or actually, band technology is employed in computer only one side of the modulated wave en- modems, and vestigial sideband (VSB) velope. Normally symmetrical about one has been developed for use in digital single sideband transmissions were made axis, the envelope was missing one en- television. from Long Island, New York, to London, tire half. What was this all about? The existence of sidebands as distinct England. In 1927 a regular two-way Inside the issue, there was no “On The from a carrier was first determined math- transatlantic low-frequency radiotele- Cover” to explain the picture. Rather, ematically in 1914. A year later, John R. phone circuit using sideband technology there were an editorial and three articles Carson, an engineer working for AT&T, opened for commercial use at a cost of all devoted to introducing hams to the invented sideband technology for use in $75 for a three-minute call (that’s about arcane subject of “s.s.s.c.”—single-side- long distance telephone carrier circuits as $760 in today’s money!). band, suppressed carrier. The articles also a means of increasing the number of calls It wouldn’t take hams long to take note discussed the messy state of the ham that could be transmitted simultaneously. of this new technology. A series of three bands, clogged as they were with fre- Carson’s invention, which involved the articles on sideband by Robert Moore, quency-hogging AM signals often inter- use of filters to remove a carrier and one W6DEI, appeared in the Amateur Radio fering with one another. “In the usual sideband while passing the other through, magazine R/9 in 1933 and 1934, and QST present-day snarl of ’phone interference,” was patented in England that same year, Technical Editor James Lamb, W1CEI, QST editorialized, “we have the piercing but court litigation held up his US patent published the magazine’s first article on shrieks of heterodynes.” It went so far as until 1923. In January of that year, the the subject, “Background for Single- to predict boldly that “everything points first experimental one-way transatlantic Side-Band ’Phone” in October 1935. An to s.s.s.c. becoming the accepted amateur method in the near future.” The three ar- Figure 1—This photo, from the February 1948 issue of QST, was captioned: ticles that appeared in the issue laid the “Although full technical information on the groundwork for the transformation of single-sideband Amateur Radio that was to come over the suppressed-carrier next quarter-century. For most hams, the transmitter at W6YX is strange-looking oscilloscope pattern on not available at this time, this photograph the cover was to be their first introduc- shows Dave Thomson, tion to what would eventually come to be W6VQB, pointing out simply called “sideband” or “SSB.” the final amplifier to Robert D. Smith, Enormous Impact W6QUW, president of the Stanford Radio If there has been a technical advance- Club… The transmitter ment that distinguished ham radio over was designed by the past half-century, it would have to be Oswald G. Villard, Jr, W6QYT, of the electrical single sideband. The move from AM to engineering faculty at SSB would be as controversial in its time Stanford University.” From January 2003 QST © ARRL Figure 3—This ad, for Eldico, features the company’s new 7-tube, 5-W sideband rig. “Everyone can now enjoy all the benefits of single sideband transmission,” the ad proclaims. Figure 2—This full-page ad for Eimac tubes, published in the July 1948 issue of QST, touts the advantages of SSSC. editorial introduction to his article noted altering the course of ham radio. built to communicate with W6YX in “A that by “action of the 1933 A.R.R.L. Single-Sideband Transmitter for Amateur Board Meeting, the technical staff of QST W6QYT at Stanford Operation.” A follow-up Stray the follow- was instructed to investigate the feasibil- It was experimental sideband work ing month showed a photo of the Stanford ity of single-side-band carrierless ’phone begun in 1947 on the 75 and 20 meter station. See Figure 1. transmission on amateur frequencies.” bands at W6YX, the Stanford Radio Club The following month, a full-page ad- Some sideband experimentation was car- at Stanford University in California2 that vertisement by the National Company in ried out in the mid-1930s by a small inspired the series of January 1948 ar- QST extolled the possibilities of duplex group of hams,1 but it was hampered by ticles in QST. In the issue, Assistant Tech- sideband. By April, QST Technical Edi- technological limitations of equipment at nical Editor Byron Goodman, W1DX, tor George Grammer, W1DF, was able to the time. World War II changed all of that, described this new mode of communicat- prognosticate: making enormous advances in radio tech- ing in “What Is Single-Sideband Tele- It may not be too much of an exaggera- nology. After hostilities ended and Ama- phony?” In addition, Oswald Villard, tion to say that our present-day ’phone teur Radio resumed, there was no longer W6QYT, of Stanford, explained the re- methods will be just as obsolete, a few any technological reason for sideband to sults of his club’s test transmissions and years from now, as spark was a few years stay on the sidelines and a very pressing informed hams how to go about tuning after c.w. got its start. “Old-fashioned need for a communications mode that in these new signals (“it is very desirable ’phone” will eventually be something that would occupy less bandwidth than did to use the minimum r.f. gain setting when can be tolerated only where there is plenty 3 AM and so free up space on ham frequen- the b.f.o. is used for demodulation,” he of room for it. cies. Sideband was exactly what the doc- would write, advice repeated through In July of the same year, Byron tor ordered, and a concerted push by the many issues of QST for hams unaccus- Goodman’s column “On the Air with ARRL would effectively spread the word, tomed to tuning in these strange-sound- Single Sideband” debuted in QST, keep- ing signals). Finally, Art Nichols, ing hams informed of the increased side- 1Notes appear on page 47. WØTQK, detailed the sideband rig he band activity in the United States and From January 2003 QST © ARRL around the world. The same issue also communications systems, his company, featured a full-page ad for tetrodes from Collins Radio, would end up making Eitel-McCullough specifically aimed at arguably the largest single contribution sideband enthusiasts. See Figure 2. It was to amateur use of SSB when, in 1955, it a sign that the radio industry was begin- all but abandoned production of AM gear ning to see the potential of a market in and threw its considerable resources be- equipment for amateur sideband use. hind development of sideband gear, hav- Another sure sign of sideband’s poten- ing prepared the way with a series of tial could be gauged by letters to the edi- full-page “Engineering Notes” that ap- tor in QST. In October 1948, a writer peared in QST in late 1954. In May of decried “single-sideband gibberish,” and 1957 Collins would make history with the accused the magazine of “trying to shove launch of the KWM-1 transceiver, “the it down the throats of the ham fraternity.” first mobile transceiver,” the advertise- But more hams than not were open to the ment in QST read, “and the first to offer possibilities that sideband offered, real- SSB.” A review of the rig in the April izing that it offered a solution to the very 1958 issue would be positively glowing: real problems that plagued the ham It is the writer’s opinion that the KWM- bands. “I personally have had no experi- Figure 4—This photo of General Curtis 1 may well mark the end of one era and the LeMay, then K3JUY/K4RFA, from the July ence as yet with single sideband,” wrote 1961 issue of QST, announced his beginning of another. This unit is more than a Canadian ham in the December issue, nomination as chief of staff of the US Air another piece of ham gear; it could be a “but anything that may relieve the over- Force. During the mid ’50s, Gen LeMay way of life (in Amateur Radio).5 crowded conditions of our bands today had converted Strategic Air Command communications from AM to SSB, based Byron Goodman’s column “On the Air and make for QRM-free QSOs, I’m all on his ham experience with the newer With Single Sideband” was discontinued for it.” mode.
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