Teletext in Salt Lake City, Utah premiered a teletext service using Ceefax. They were followed by television network CBS, which carried out preliminary tests on both the British Teletext and the rival French Antiope system. One of the most prominent providers was the "Electra" teletext service, using World System Teletext (WST), broadcast from the early 1980s on American cable channel WTBS. Electra also carried another teletext service on its higher-numbered pages, a service called "Tempo". "Tempo" mainly carried sports (and other miscellaneous) information on its pages. At the time of Electra's closing in 1993, it was the only existing teletext service
Teletext economic Teletext system with 1971 technology. However, as low cost was essential to the project's long term success, this obstacle had to be overcome. Meanwhile, the General Post Office (GPO), whose telecommunications division later became British Telecom, had been researching a similar concept since the late 1960s, known as Viewdata. Unlike Teledata which was a one-way service carried in the existing TV signal, Viewdata was a two-way system using telephones. Since the Post Office owned the telephones, this was considered to be an excellent way to drive more customers to use the phones. In 1972 the BBC demonstrated their system,