Ceefax

Ceefax was the world's first teletext information service and a forerunner to the current BBC Red Button service. Ceefax was started by the BBC in 1974 and ended, after 38 years of broadcasting, at 23:32:19 BST (11:32 PM BST) on 23 October 2012, in line with the digital switchover being completed in Northern Ireland.

To receive a desired page of text on a Ceefax-capable receiver, the user would enter a 3 digit page number on the device. Once the page number was entered, the selected page would display on the user's screen after a number of seconds delay. There were many pages to choose from.

Early electro-mechanical system
During the late 1960s, engineers Geoff Larkby and Barry Pyatt, at the Designs Department (Television Group) of the BBC, worked on an experimental analogue 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 Greene, 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".

Their system employed a modified, Alexander Muirhead designed, rotating drum, facsimile transmitter, and Larkby & Pyatt's own, unique, design of hard-copy printer. This printer used pressure-sensitive "till-roll" paper passing over a drum with a raised helix of steel wire. The drum was synchronised with the transmission drum by means of the "Start of Page", and "Start of Line" information inherent in the Muirhead system. Printing was effected by a hardened steel blade driven by, initially, a loudspeaker-type moving coil, then by a printed-circuit coil, and finally by a special ceramic piezo element manufactured by Brush-Clevite. The combination of rotating helix and oscillating moving blade, with the till-roll paper moving linearly between them, enabled a raster to be drawn on the paper.

Fully-electronic version
Early test data being received in 1972 – a pangram and numbers

The idea was later taken up again, this time in digital and on-screen form, under the new name of CEEFAX, and the new 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. Created in the United Kingdom in the early 1970s by the Philips Lead Designer for VDUs John Adams, his design was given to the BBC so they could start transmission. BBC were working on ways of providing televisual subtitles for deaf people, 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 and 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 1974 on a single standard, different from both Ceefax and ORACLE, which ultimately developed into World System Teletext (1976), and which remained in use for analogue broadcasts until 2012. 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.[citation needed]

The basic technology of Ceefax remained compatible with the 1976 unified rollout; system elaborations in later years were made such that earlier receivers were still able to do a basic decode of pages, but would simply ignore enhanced information rather than showing corrupted data.[citation needed]

Closure
Until 2012, the BBC's Ceefax service was still providing information on topics covering News, Sport, Weather, TV Listings and Businesses. The pages were kept up to date until the UK digital switchover was completed on Tuesday 23 October 2012.

In 2002, the BBC stopped broadcasting Ceefax on the digital satellite Sky Digital service, but later brought back a limited service including a TV schedule for BBC One and BBC Two; and subtitles.

The BBC has tried to reuse the old Ceefax page numbers where possible on the Freeview and digital satellite BBC Red Button Ceefax-replacement services.

It was announced that Ceefax would not be replaced when the analogue signal was switched off in October 2012. The BBC Red Button service was seen as an alternative to Ceefax and since 2007 the number of regions with a Ceefax supported analogue signal had declined as digital switchover progressed across the UK. As of the end of 2011, three-quarters of the UK TV regions had completed or were in the process of being switched over.

Ceefax was the last remaining text service available via analogue TV transmissions in the UK, as ITV and Channel 4's Teletext service closed in December 2009. Channel 5's "Five Text" ancillary service closed in 2011. A limited analogue teletext service through ITV and Channel 4 was still available through terrestrial until the digital switchover was completed on 23 October 2012.

At 23:32:19 BST on 23 October 2012, Ceefax was switched off after 38 years of providing news, weather and sport information when the Olympic Games champion Dame Mary Peters turned off the last analogue TV signal in Northern Ireland. A series of graphics on Ceefax's front page marked its 38 years on the BBC. BBC News' website also has memories of Ceefax.

In a tongue-in-cheek article on the 2017 general election, The Guardian gave political satirist Lord Buckethead a "Best Policy" award for the latter's manifesto pledge to bring back Ceefax.