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For the album by Fridge, see Ceefax (album).
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]
[edit] HistoryThe system was announced in October 1972 and following test transmissions in 1973-1974 the Ceefax system went live on the 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 in 1976 settled upon a single standard—different from both Ceefax and Oracle—which is still in use for analogue broadcasts as of 2008; and which ultimately developed into World System Teletext. The display format of 24 rows by 40 columns of characters was also adopted for the Prestel system. In March 1980 the BBC channel BBC2, then followed by BBC1, began to transmit experimental teletext pages in-vision, generally for the 30 minutes before programmes began. From May 1983 in-vision pages were filling in the entire length of BBC1 daytime closedowns, whilst on BBC2 from that date they were shown from 9am until the start of programmes as well as filling daytime intervals and closedowns. Also in 1983, after Channel 4 and S4C had launched, pages from 4-Tel, ORACLE and even SBECTEL were transmitted in-vision. ITV finally transmitted ORACLE pages in-vision in 1987 before TV-am began, although the advent of 24-hour broadcasting on ITV meant that ITV's in-vision ORACLE broadcasting was short-lived. 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. Early receivers do not see the FastText coloured-button hyperlinking data, so the system ignores it. As of 2008 the BBC's Ceefax service was still providing information on a wide range of topics covering News, Sport, Weather, TV Listings and Businesses. The pages were 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. Since 2006, the BBC has been promoting the reuse of the Ceefax page numbers on the Freeview and digital satellite BBC Red Button Ceefax-replacement services. 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.[3] [edit] TechnologyCeefax 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] Pages from CeefaxThose without access to teletext-equipped sets can still view limited Ceefax content via the Pages from Ceefax slot on BBC Two. This consists of selected Ceefax pages (typically news) transmitted as an ordinary TV picture. As a result, although Pages from Ceefax can be viewed on any set, there is no interactivity or choice, rather diminishing the purpose of the original concept. The audio accompaniment for Pages from Ceefax broadcasts typically consists of some form of easy listening music (between 2000 and 2005 the music was typically sourced from music production libraries such as Funtastik, KPM or BMG Zomba, or sometimes a discontinuous tone. Since 2006, the music is now completely sourced from Funtastik music. Pages from Ceefax is normally only shown by the BBC in the absence of any other programming. Once a common filler during daytime (where it was occasionally billed as Ceefax in Vision or, in the case of the pre-Breakfast Time 6am slot between 1983 and 1989, as Ceefax AM), it has been marginalised by the move towards a near-continuous service, where in recent years BBC News would be placed in late night/early morning gaps in schedules. The BBC News channel has a higher preference over Ceefax when BBC One and Two have 'technically' closed down in the early hours of the morning. When scheduled programming on BBC One ends, typically around 4am, they will revert to broadcasts from BBC News. BBC Two also does this, but if both channels have ended scheduled programming, then BBC One has priority over BBC News, while BBC Two will turn to Pages from Ceefax. For a period between September 2005 and December 2006, there was a weekday gap between 6am and 7am on BBC Two that saw Pages From Ceefax broadcast. During the Christmas period, when The Learning Zone is off air, Ceefax is shown through the night on BBC2. The Learning Zone saw a reduction in its airtime in 2007, so Ceefax is now the filler following the end of programmes on Friday, Saturday and Sunday nights plus every night during the summer school holidays (July - September). The last BBC One network broadcast took place on 9 November 1997, although it is still occasionally shown on BBC One Scotland, normally to fill the gaps between opt-outs and The Sign Zone. The selection of pages broadcast now is significantly smaller than that shown until the late 1990s. The limited set of rolling pages shown on Pages from Ceefax (referred to as a "newsreel") are also accessible at any time of day via Ceefax page 152 (BBC Two only. BBC One no longer has this page.) on any analogue teletext television. [edit] References
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