Teletext systems expensive cost of NABTS decoders, costing in the thousands of dollars upon their release to the public. NABTS, however, was adopted for a short while by American TV networks NBC & CBS throughout the early-to-mid 80s, CBS using it for their short-lived ExtraVision teletext service, which premiered after the early Antiope & Ceefax trials by CBS & KNXT, and NBC, who had a NABTS-based service called NBC Teletext for a very short time in the mid-1980s. NBC discontinued their service in 1985 due to the cost of NABTS decoders not dropping to an affordable level for the consumer public. The
Channel Four Television Corporation service to provide schedules, programme information and features. The original service was called 4-Tel and was provided in collaboration with Oracle. In 1993, with Oracle losing its franchise to Teletext Ltd, the running of 4-Tel was taken over by Intelfax, and in 2002 was renamed FourText. In 2003, Channel Four awarded Teletext Ltd a 10-year contract to run an ancillary teletext service, named Teletext on 4, on a number of its channels. The service was provided on both Channel 4 analogue and digital television services, "Channel 4", "E4" and "More4". This has now been ceased and Teletext is no longer