WST saw some use in the United States in the 1980s, for the Electra service, which was carried on SuperStation WTBS (now TBS). WST is used for all teletext services in Europe & Scandinavia, including Ceefax from the BBC and services from Teletext on ITV in the United Kingdom, ZDFtext from ZDF and ARDText from ARD in Germany, and Tekst-TV from NRK in Norway, among many other teletext services offered by other television networks throughout the European continent. It was accepted by CCIR in 1986 under international standard CCIR 653 (now ITU-R BT.653) as one of four recognised standards for teletext worldwide (most commonly referred to as CCIR Teletext System B).Īlmost all television sets sold in Europe since the early '80s have built-in WST-standard teletext decoders as a feature. With some tweaks to allow for alternative national character sets, and adaptations to the NTSC 525-line system as necessary, this was then promoted internationally as "World System Teletext". WST originally stems from the UK standard developed by the BBC and the UK Independent Broadcasting Authority in 1974 for teletext transmission, extended in 1976 as the Broadcast Teletext Specification. It was adopted into the international standard CCIR 653 (now ITU-R BT.653) of 1986 as CCIR Teletext System B. World System Teletext ( WST) is the name of a standard for encoding and displaying teletext information, which is used as the standard for teletext throughout Europe today.
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