Ceefax
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| Broadcast area | National UK |
|---|---|
| Launched | 23 September 1974 |
| Owned by | BBC |
Ceefax (phonetic for "See Facts") is the BBC's teletext information service transmitted via the analogue signal, starting in 1974 and running until 2012.[1][2]
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[edit] History
The system was announced in October 1972 and following test transmissions in 1973-74 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. The then-BBC Director of Engineering James Redmond 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. 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 2009 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.
Channel 4 also showed pages from Oracle and its programme-related teletext service 4-Tel during the daytime from 1983 onwards. Oracle pages were never seen on ITV during the daytime but by 1987, some ITV regions were broadcasting all through the night and occasionally Oracle pages were shown before the breakfast service from TV-am began.
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.
[edit] Modern day
As of 2009, the BBC's Ceefax service is still providing information on a wide range of topics covering News, Sport, Weather, TV Listings and Businesses. The pages are still kept extremely up-to-date. Before the advent of the Internet, Ceefax pages were often the first location to report a breaking story or headline.
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 attempted to reuse the old Ceefax page numbers where possible on the Freeview and digital satellite BBC Red Button Ceefax-replacement services.[3]
As of 2008, it is expected that Ceefax will not be replaced when the analogue signal is switched off in 2012, instead the BBC is developing IPTV.[1]
Ceefax will be the last remaining analogue text service on UK television when ITV and Channel 4's Teletext service close in December 2009.
[edit] Technology
Ceefax uses the World System Teletext standard (originally CEPT1). As with other teletext systems, text and simple graphics are transmitted in-band with the picture signal, and decoded by controller circuitry.
[edit] References
- ^ a b Pete Clifton Points of View 9 November 2008
- ^ Test Cards and Ceefax BBC Archive
- ^ How we assign our page numbers BBC Blogs
[edit] External links
- Ceefax at bbc.co.uk
- Online representation of today's Ceefax
- More information and captures of CEEFAX pages
- BBC News article celebrating 30th anniversary of Ceefax
- View Ceefax on an Apple Mac using the Mac OS X Dashboard feature
- View Ceefax on a Chumby
- "Pages from Ceefax" at Everything2
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