Originally conceived to follow the UK
Prestel specifications, and developed on contract by a small UK company called
Systems Designers Ltd (originally merged into
EDS and now part of
HP) for
IBM Germany. Btx added a number of additional features before launch, including some inspired by the French
Minitel service, to create a new display standard of its own, which in 1981 was designated the
CEPT1 profile. The system was presented at the IFA in
Berlin, with a trial system installed in
Düsseldorf and Berlin in 1980. In 1981, the system was expanded to rest of Germany, with the necessary network being developed by
IBM. The system was launched nationwide in 1983, at the press of a button by the Federal Post Minister at Berlin's IFA The service could only be used with a modem produced by the Bundespost and user uptake was low. The "MultiTel" devices could operate without a TV and allowed simultaneous telephone operation. By 1986, there were also adaptor devices for home computers like the
Commodore 64 (ex: Siemens Decoder Module II). By the 1990s, the system was renamed "Datex-J" and focused on the home users. In 1995, an enhanced backward-compatible standard called Kernel for Intelligent Communication Terminals (KIT) was announced, but this never really gained acceptance. Btx formed the basis of
T-Online, Deutsche Telekom's online service, which maintained a Btx interface in its access software after the T-Online brand was introduced in 1995. After
German reunification, Btx was available throughout
Germany. Btx was also available in
Austria and
Switzerland, where it was called
Videotex (VTX). The last Btx access was switched off at the end of 2001 by
Deutsche Telekom; it had been made obsolete by the
Internet. ==Operation==