>>> 2025-08-25 teletext in north america (PDF)
I have an ongoing fascination with "interactive TV": a series of efforts, starting in the 1990s and continuing today, to drag the humble living room television into the world of the computer. One of the big appeals of interactive TV was adoption, the average household had a TV long before the average household had a computer. So, it seems like interactive TV services should have proliferated before personal computers, at least following the logic that many in the industry did at the time.
This wasn't untrue! In the UK, for example, Ceefax was a widespread success by the 1980s. In general, TV-based teletext systems were pretty common in Europe. In North America, they never had much of an impact---but not for lack of trying. In fact, there were multiple competing efforts at teletext in the US and Canada, and it may very well have been the sheer number of independent efforts that sunk the whole idea. But let's start at the beginning.
The BBC went live with Ceefax in 1974, the culmination of years of prototype development and test broadcasts over the BBC network. Ceefax was quickly joined by other teletext standards in Europe, and the concept enjoyed a high level of adoption. This must have caught the attention of many in the television industry on this side of the ocean, but it was Bonneville International that first bit [1]. Its premier holding, KSL-TV of Salt Lake City, has an influence larger than its name suggests: KSL was carried by an extensive repeater network and reached a large portion of the population throughout the Mountain States. Because of the wide reach of KSL and the even wider reach of the religion that relied on Bonneville for communications, Bonneville was also an early innovator in satellite distribution of television and data. These were ingredients that made for a promising teletext network, one that could quickly reach a large audience and expand to broader television networks through satellite distribution.
KSL applied to the FCC for an experimental license to broadcast teletext in addition to its television signal, and received it in June of 1978. I am finding some confusion in the historical record over whether KSL adopted the BBC's Ceefax protocol or the competing ORACLE, used in the UK by the independent broadcasters. A 1982 paper on KSL's experiment confusingly says they used "the British CEEFAX/Oracle," but then in the next sentence the author gives the first years of service for Ceefax and ORACLE the wrong way around, so I think it's safe to say that they were just generally confused. I think I know the reason why: in the late '70s, the British broadcasters were developing something called World System Teletext (WST), a new common standard based on aspects of both Ceefax and ORACLE. Although WST wasn't quite final in 1978, I believe that what KSL adopted was actually a draft of WST.
That actually hints at an interesting detail which becomes important to these proposals: in Europe, where teletext thrived, there were usually not very many TV channels. The US's highly competitive media landscape lead to a proliferation of different TV networks, and local operations in addition. It was a far cry from the UK, for example, where 1982 saw the introduction of a fourth channel called, well, Channel 4. By contrast, Salt Lake City viewers with cable were picking from over a dozen channels in 1982, and that wasn't an especially crowded media market. This difference in the industry, between a few major nationwide channels and a longer list of often local ones, has widespread ramifications on how UK and US television technology evolved.
One of them is that, in the UK, space in the VBI to transmit data became a hotly contested commodity. By the '80s, obtaining a line of the VBI on any UK network to use for your new datacasting scheme involved a bidding war with your potential competitors, not unlike the way spectrum was allocated in the US. Teletext schemes were made and broken by the outcomes of these auctions. Over here, there was a long list of television channels and on most of them only a single line of the VBI was in use for data (line 21 for closed captions). You might think this would create fertile ground for VBI-based services, but it also posed a challenge: the market was extensively fractured. You could not win a BBC or IBA VBI allocation and then have nationwide coverage, you would have to negotiate such a deal with a long list of TV stations and then likely provide your own infrastructure for injecting the signal.
In short, this seems to be one of the main reasons for the huge difference in teletext adoption between Europe and North America: throughout Europe, broadcasting tended to be quite centralized, which made it difficult to get your foot in the door but very easy to reach a large customer base once you had. In the US, it was easier to get started, but you had to fight for each market area. "Critical mass" was very hard to achieve [2].
Back at KSL, $40,000 (~$200,000 today) bought a General Automation computer and Tektronix NTSC signal generator that made up the broadcast system. The computer could manage as many as 800 pages of 20x32 teletext, but KSL launched with 120. Texas Instruments assisted KSL in modifying thirty television sets with a new decoder board and a wired remote control for page selection. This setup, very similar to teletext sets in Europe, nearly doubled the price of the TV set. This likely would have become a problem later on, but for the pilot stage, KSL provided the modified sets gratis to their 30 test households.
One of the selling points of teletext in Europe was its ability to provide real-time data. Things like sports scores and stock quotations could be quickly updated in teletext, and news headlines could make it to teletext before the next TV news broadcast. Of course, collecting all that data and preparing it as teletext pages required either a substantial investment in automation or a staff of typists. At the pilot stage, KSL opted for neither, so much of the information that KSL provided was out-of-date. It was very much a prototype. Over time, KSL invested more in the system. In 1979, for example, KSL partnered with the National Weather Service to bring real-time weather updates to teletext---all automatically via the NWS's computerized system called AFOS.
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