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 systems Guide+ equipped sets from RCA even had an IR-emitting sensor that could be plugged into the back of the TV, to control a VCR to record programs which could be selected from the on-screen Guide+ listings. In some ways, this was very similar to the Video Programming by Teletext|Video Programming by Teletext (VPT), Video Program System (VPS), and Programme Delivery Control (PDC) features of British/European teletext. Guide+ was a free service, supported by advertisements displayed on-screen in the Guide+ menu and listing screens, not unlike banner ads displayed on web pages. Guide+ was delivered over the VBI of select local