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
Teletext Teletext Teletext (or broadcast teletext) is a television information retrieval service created in the United Kingdom in the early 1970s by the Philips Lead Designer for VDUs, John Adams. Teletext is a means of sending pages of text and simple geometric shapes from mosaic blocks to a VBI decoder equipped television screen by use of a number of reserved vertical blanking interval lines that together form the dark band dividing pictures horizontally on the television screen. It offers a range of text-based information, typically including news, weather and TV schedules. Paged subtitle (or closed captioning) information is also transmitted within