A Global Look at Teletext

Summary

Brief explanation Teletext is a weird technology. Although often ridiculed as completely archaic, it’s very popular in many countries still today. It seems like the public broadcasters in Europe just can’t get people to stop using it, no matter what new services they provide.You most likely know teletext in the British version, with blocky text graphics in few colours, that came intertwined with the analogue TV-signal. This is called World System Teletext. But that was only the beginning. Teletext came in vector and pixel graphics, it was used for games and multimedia… there was even FM and PCM audio for teletext in Japan!When you take a global perspective on teletext, it’s actually quite hard to say what teletext is. But let’s start in the UK in the 1970’s, when teletext was used for subtitles and text-based screens that you could flick through with your remote control. Young teletext In 1971, Philip’s engineer John Adams wrote a technical proposal to use the “invisible” part of the TV-signal (VBI) to transmit closed captions for the hearing impaired.* This was the starting point of three government bodies in the UK developing their own standards. BBC and IBA developed their own systems, agreed on a common standard (p.106), and launched Ceefax (1974) and ORACLE (1978) respectively. The third standard was the videotex-standard Prestel from the British Post Office. Teletext Level 1 (1976) featured two character sets: a basic ASCII-like one, and a graphical one with so-called sixels. The screen was 40×24 characters and there was a palette of 7 predefined colours. Control codes, like switching between colours or character sets, required using an empty character on the screen. Level 1.5 (1981) added support for national character sets and it remains the most widely used teletext standard today. These British standards became known as World System Teletext (WST).🡆 UK teletext posts🡆 Galax Teletext lets you teletextify your websiteThere was a teletext alternative that off...