May 1962 Popular Electronics
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Wax nostalgic about and learn from the history of early electronics. See articles
published October 1954 - April 1985. All copyrights are hereby acknowledged.
When UHF broadcast television was being introduced, pundits - as pundits often do - were quick to predict the rapid, imminent demise of the VHF channels. To wit, "All current VHF stations (operating on channels 2 through 13) may be scrapped, and operations shifted to the UHF band." That was in 1962, when the first experimental UHF station (WUHF) went on-air in New York City. Cited as the reason was a supposed inability for the two bands to co-exist. VHF channels 2-6 are on 54-82 MHz, 7-13 are on 174-210 MHz, and UHF channels 14-83 are on 470-884 MHz. History proved otherwise, due largely to UHF signals' inability to bend around natural and manmade obstruction and provide a clear signal. This story is a very nice account of the early days of UHF television broadcasting.
Must We Have UHF-TV?
The odds are stacked 70 to 12 that we will.
By Ken Gilmore
Antennas in cover photo and on page 41 courtesy of JFD Electronics Corporation, 6101 16th Ave . Brooklyn 4, N. Y.
Last fall, a new television station went on the air in New York City. Since New York already has six active channels, a seventh might seem barely newsworthy. And when you consider that less than 1% of the area's viewers are equipped to receive this new channel, it seems hardly worth mentioning. Yet the fact is that New York's new station - WUHF, telecasting on ultra-high-frequency channel 31 - may turn out to be the most important television station in the United States.
The results of tests now being conducted by WUHF are likely to have a profound effect on the nation's entire television setup. All current VHF stations (operating on channels 2 through 13) may be scrapped, and operations shifted to the UHF band - channels 14 through 83, now receivable by only a small fraction of the nation's TV sets. This means that even though you may now live in one of the country's few UHF areas, your present TV set probably isn't equipped to pick up the new channels. To watch UHF TV, you'll either have to add a UHF converter or buy a new set.
Bow-Tie UHF Reflector
Suitable for distances up to 25 miles. Has peak gain of 4 db.
Bow-Tie UHF Corner Reflector
Ideal for reception at distances of 25-50 miles. Peak gain of 9 db.
Like bow-tie reflector but uses four bow ties. Furnishes gain of 8 db. Six-bay bow-tie unit has 10-db gain and range up to 100 miles.
4-Bay UHF Bowtie Reflector
Designed for single-channel reception. Has 12.5-db gain for excellent results at 75 miles; 16 elements will stretch range to 100 miles.
The Mess in TV. These drastic proposals are designed to do something meaningful about an inescapable fact: the present TV bands are in a mess. Stated very simply, there just aren't enough VHF channels to go around.
Many cities have only one or two TV stations, and consequently have to struggle along with extremely limited TV fare. Added stations in these cities would only interfere with existing stations in nearby cities. With the present 12-channel VHF system, all but a hand-full of the more than 500 possible VHF stations are already on the air, and the few more which could be are in remote areas where there simply isn't enough population to support them.
Many plans have been proposed to straighten out the mess. But the conviction is growing that only one scheme really has a chance to succeed: throw out the present VHF band and shift everything to UHF. Why UHF? Because the UHF band (channels 14-83) offers an abundance of possible TV stations - 1500 or so across the country; although only about a hundred are in actual operation, for one reason or another.
Actually, because of its relative disuse, the vast expanse of the UHF spectrum has become the favorite target for space scientists, military leaders, and international communications companies. All of these groups need spectrum space desperately and have many uses to which they would like to put the UHF TV band. If television broadcasters won't take advantage of it, they say, let's take it away from the TV people and give it to those who will. To find out why this situation exists, let's take a quick look at TV over the years.
Looking Back. Television's current difficulties began back in the late 1940's when the then new broadcasting medium became an overnight success - a far bigger one than anyone had thought possible. Within a few years after the end of World War II, millions of TV sets were bought by eager audiences around the country. Television stations sprang up as fast as the FCC could license them. The country's big cities - New York, Los Angeles, Chicago, and others - quickly applied for and got many channels; they are the only areas, for the most part, which now have enough stations.
Far more quickly than anyone could predict, a large percentage of the available channels were in operation and there was still a terrific clamor for the few which remained. The basic trouble was that there were only 12 channels available. Since two stations transmitting on the same channel must be several hundred miles apart to keep from interfering with one another, only about 550 stations could be fitted into the 12 channels across the country.
Many smaller towns and cities found that most channels had already been grabbed up when they themselves got around to applying. Suddenly realizing there wouldn't be enough to go around, the FCC, in desperation, turned on The Freeze. For several years, the Commission turned over the thorny problem of what to do to its best legal and engineering minds. In 1952 they announced a solution: Establish 70 new channels in a new, ultra-high-frequency band, and at the same time retain the older VHF channels.
Peaceful Coexistence? The two systems, it was thought, could peacefully co-exist. Unfortunately, the decision turned out to be a short-sighted one, though for a while it appeared to have a chance of success.
When the freeze lifted and the FCC again began taking applications for new stations in 1952, 200 of the first 500 applications were for stations in the newly created UHF band. The reason: some telecasters were eager to get on the air with the new stations and get the jump on competition. Since there was vigorous competition for the few remaining VHF's, many broadcasters were able to get a UHF license, build the station, and begin broadcasting, while the VHF channels were still tied up in hearings.
But by 1955, it was clear that the U stations were in serious trouble. As the V's continued coming on the air, the U's began falling like flies in a hailstorm. During the first three years, 131 of the authorized U's failed, 39 of them without ever having fired a kilowatt. For every VHF station that went out of business during the period, six U's couldn't make it, in spite of the fact that there were far fewer U's to begin with. The highest number of U's on the air at one time during the entire history of UHF was 171. Today, that number has shrunk to about 90 commercial operations - half of them are in trouble - and a sprinkling of educational U's.
The ultra-high-frequency stations couldn't compete for two reasons. First, their signals didn't go as far. A 100-kw. VHF station broadcasts a usable signal over a far greater area than a UHF station of the same power. This made advertisers reluctant to buy time on the U's with their smaller audience.
Second, and even more important, a very small proportion of televiewers across the country were willing to convert their sets to receive the UHF transmissions, or to buy a new television set with built-in provisions for covering both bands. In most parts of the country, then, only a small percentage of the potential audience could receive UHF signals.
4-Bay UHF Bow-Tie Reflector
Like a bow-tie reflector but uses 4 bow ties. Furnishes gain of 8 db. Six-bay bow-tie unit has 10 db gain and range up to 100 miles.
The old chicken-and-egg problem cropped up: operators didn't want to build new UHF stations until there were enough receivers to make it worthwhile, and home viewers wouldn't buy UHF sets until there was something to see on them. Also, networks didn't want to affiliate with the few U's which did exist until they had larger audiences, and at the same time, the U's couldn't attract the audiences without the network programs. Consequently, the vast majority of the UHF channels have lain idle.
Other Possibilities. Over the years, the FCC has made a number of attempts to do something about this sorry situation. First, it instituted a crash program to "de-intermix"; that is, whole cities would be made either all V or all U, so that stations in any community could compete on an even basis. This raised a howl from holders of VHF channels that hasn't died down yet. The de-intermix program never really got off the ground.
The FCC was diverted, for one thing, by a plan to increase the number of VHF stations from 12 to 50. Unfortunately, this scheme required that the military services give up a block of frequencies adjacent to the present television band. After considerable study, the military delivered the answer: NO. This left the Commission with only three choices.
- Give up and admit defeat.
- Keep both the UHF and VHF bands, and try to take measures to put them on a more competitive basis.
- Shift all stations to the UHF band in spite of the screams of rage from present holders of the highly profitable VHF outlets.
Although all three approaches have their advocates, everybody agrees on one thing: if more new stations - desperately needed in some parts of the country - are to be had, then somehow the FCC must find a way to breathe life back into the UHF corpse.
With that goal in mind, the FCC is deliberating on a compromise program - not even all Commissioners agree on the best approach - and will presumably come to some firm decision in the next few months. Tentatively, the plan involves keeping both the VHF and UHF bands-at least for the time being, and at the same time launching a vigorous program to make the U's more competitive. The main provisions of the plan:
What You'll Need For UHF TV
A UHF converter (see photo above) is all you'll need to pick up UHF TV stations in your area. For best results, use separate antennas for VHF and UHF (see diagram below).
If you, like most televiewers, are currently equipped only for standard VHF reception, you'll want to know how you can pick up UHF programs when they are broadcast in your neighborhood. Let's say you want to keep your present TV set. In this case, you can just add a separate converter to it, such as the Blonder-Tongue 99R which sells for $22.95 (list). If you're thinking about buying a new set anyway, you'll want to consider one with a built-in UHF tuning section; such a receiver will probably cost only $20 to $40 more than a similar set without this feature.
You may have to do something about your antenna, too. The UHF signals - ranging from channel 14, transmitting on 470-476 mc., to channel 83, transmitting on 884-890 mc. are on too high a frequency to be picked up efficiently on VHF antennas. If you need an outside VHF antenna now, chances are you'll need a separate outside antenna for UHF, too; such an antenna will cost you from $5 to $35, depending on how far you are from the station. On the other hand, if you now get by with rabbit ears on top of your set, a similar (but smaller) UHF unit may do the trick.
Remember, the prices above are today's prices. Given a nationwide mass market, UHF television set and antenna manufacturers will be able to tumble costs considerably.
- Begin a stern program of de-intermixture, in spite
- Take an unequivocal public stand in favor of promoting UHF broadcasting.
- of the vigorous protests which are bound to result. As a matter of fact, the Commission has already tentatively selected eight urban areas* to be switched to all-UHF service.
- Relax some engineering standards now required in the construction of UHF stations. This would allow operators to build and run UHF stations more cheaply than at present.
- Encourage VHF operators to build UHF transmitters and broadcast the same programs on the two channels simultaneously. The idea here is to urge telecasters to build in anticipation of an eventual switch to all-UHF service. (Reserve your channel now, the FCC is saying, and you can have your pick of the desirable low-numbered channels - wait until later, and they may all be gone.)
- Eliminate competitive hearings on new UHF stations. If an applicant meets the minimum standards and there are no other applicants, he gets the license without argument.
- Sponsor a bill in Congress to require that all TV sets shipped in interstate commerce be equipped to receive both VHF and UHF broadcasts. This would make it far easier for new U's to go on the air, by giving them ready-made potential audiences.
UHF Test Tube. In addition, the FCC has launched the $2-million experiment in UHF telecasting, New York's station WUHF operating on channel 31. The program, which should be completed by 1963, is designed to test the transmission characteristics of UHF in a big city area. Thousands of householders are being supplied with UHF receivers and asked to report on reception quality.
Although the results of the WUHF experiment will not be known for some time word has it that UHF reception is about the same as VHF reception. Commissioner Robert E. Lee, for example, speaking before an IRE group shortly after the tests got under way, observed that results were "pretty encouraging" in that early reports indicated "no significant difference, within 25 miles, of low VHF, high VHF, and UHF transmissions."
An experimental ultra-high-frequency (UHF) station, New York City's WUHF has been on the air since November of 1961.
Photo shows opening ceremonies and picture New York Fire Commissioner Edward Thompson and Municipal Broadcasting System Director Seymour N. Siegel (left), FCC Chairman Newton N. Minow (seated, right), and FCC Commissioner Robert E. Lee (standing, far right).
Many industry observers feel that the whole thing is nothing but window dressing. "The Commission is planning to switch all stations to UHF as soon as it can" said one industry figure. "But they figured it would help shift public opinion if they had a test, showing that UHF reception was as good as or maybe even a little better than VHF reception. The engineers knew what the results of this test would be before it ever got started."
Whether this is true or not, it does look as though the FCC finally means business. Its dynamic young chairman, Newton Minow, says he is in favor of retaining both the U and V channels.
Without the bill requiring that sets be built to receive both V and U stations, though, Minow is doubtful about the success of the program. And at the moment - although committees in both houses of Congress have held hearings on the bill - the prospects for its passage do not look too bright.
Likely Outcome. Without such a law, feels Newton Minow, the Commission may ultimately have no alternative but to scrap the VHF band entirely, forcing all operations to the UHF band.
This step, while drastic, could be taken with a minimum of inconvenience to all concerned by careful planning. If the final date for cutting off all V's were ten years from now, for example, broadcasters could write off their transmitting equipment between now and then, and prepare for UHF operations at the same time. Home viewers, meanwhile, could continue to use their present sets until they wore out, then replace them with sets capable of receiving both kinds of broadcasts.
Although few responsible figures are willing to say it, this is likely to be the outcome. The FCC fumbled the ball in 1952 when it decided that VHF and UHF could coexist comfortably. With the lessons of experience behind it, the Commission is not likely to make the same mistake again.
Is UHF Better Than VHF TV?
At present, very little information is available from the FCC and the companies conducting the VHF/UHF comparison tests in New York City. However, there is some indication (based on 100 home installations) that VHF telecasts have a slight edge over UHF.
Nine different types of UHF antennas were tested by RCA back in the early 1950's. Shown left to right, they are: a parabolic reflector, rhombic, double-fan dipole, Yagi, a dipole variation, helical, stacked "V," single-fan dipole, and corner reflector.
In general, outdoor antennas benefit UHF somewhat more than VHF. Man-made noise seems to be a very small problem on either. Thermal noise is a bit more troublesome on UHF, but improved receiver design can eliminate this drawback. And UHF seems to be just a trifle "ghostier."
In all, some 800 to 1000 test installations are planned, with one out of every 10 using a color TV receiver. Only when all tests have been completed can definite conclusions be drawn from the compiled data, and the fate of UHF decided.
*Montgomery, Ala.; Hartford, Conn.; Champaign, Ill.; Rockford, Ill., Binghampton, N.Y.; Erie, Pa.; Columbia, S.C.; Madison, Wis.
Posted April 4, 2017