Ceefax - History

History

During the late 1960s, engineer Geoff Larkby and technician Barry Pyatt were working at the Designs Department (Television Group) of the BBC on a text transmission system. Its object was to transmit a printable page of text during the nocturnal "close-down" period of normal television transmission. Sir Hugh Carleton Green, then Director General of the BBC, was interested in making farming and stock-market prices available as hard copy via the dormant TV transmitters. The remit received by BBC Designs Department was "the equivalent of one page of The Times newspaper to be transmitted during shut-down".

The first system employed a modified Muirhead drum facsimile transmitter, and hard-copy printer using pressure-sensitive "till-roll" paper passing over a drum with a raised helix of steel wire. This drum was synchronised with the transmission drum by means of the "frame" pulse inherent in the Muirhead system. Printing was effected by a hardened steel blade driven initially by loudspeaker moving coil, then by a printed-circuit coil, and finally by a special ceramic piezo element from Brush-Clevite. The combination of rotating helix and linearly moving blade, with the moving till-roll between them, enabled a raster to be drawn on the paper, without the smoke and smell of the Muirhead "sparking" system.

This early electro-mechanical system was called BEEBFAX – "Beeb" was the popular name for the BBC, and "fax" from the facsimile machine. Initial tests were conducted by sending scans of Christmas Cards over the internal telephone system.

The system was less than popular in the Designs Department laboratory, due to the clatter of the Muirhead facsimile, and the whining of the printer; the project was shelved. Barry Pyatt, who had designed the innovative receiving and decoding electronics, went on to propose several improvements using the then emergent integrated circuit digital technology, but the project died. Geoff Larkby retired, and Barry Pyatt left the employ of the Corporation.

The idea was later taken up once again, this time in digital and on-screen form, under the new name of CEEFAX.

The system was announced in October 1972, and following test transmissions in 1972–74, the Ceefax system went live on 23 September 1974 with thirty pages of information. Developed by BBC engineers who were working on ways of providing televisual subtitles for the deaf, it was the first teletext system in the world. James Redmond, the BBC's Director of Engineering at the time, was a particular enthusiast. Other broadcasters soon took up the idea, including the Independent Broadcasting Authority (IBA), who had developed the incompatible ORACLE teletext system, at around the same time. Before the internet (via the world wide web) become popular, Ceefax pages were often the first location to report a breaking story or headline.

After technical negotiations, the two broadcasters settled in 1976 on a single standard, different from both Ceefax and Oracle, which ultimately developed into World System Teletext, and which in 2012 is still in use for analogue broadcasts. The display format of 24 rows by 40 columns of characters was also adopted for the Prestel system.

The technology became the standard European teletext system and replaced other standards, including the Antiope system formerly used in France.

In 1983, Ceefax started to broadcast computer programs, known as telesoftware, for the BBC Micro (a home computer available in the United Kingdom). The telesoftware broadcasts stopped in 1989. A similar idea was the French C Plus Direct satellite channel which used different, higher speed technology to broadcast PC software.

The basic technology of Ceefax has remained compatible with the 1976 unified rollout; system elaborations since then have been made such that earlier receivers are still able to do a basic decode of pages, but will simply ignore enhanced information rather than showing corrupted data. For example, early receivers cannot process the FasText coloured-button hyperlinking data, but are able to ignore it.