Jonathan E. Hardis said: >> There were experiments at NIST in the early days of TV to use the TV signal >> as a time dissemination source. It worked well, as coordinated with the NIST >> radio time signals. But it didn't turn out to be a practical solution. > > More specifically, the idea was to put a character code (like ASCII) in the > VIR (vertical interval reference) portion of the signal that would be the > correct time. There turned out to be little interest in the technology for > this purpose, but an alternate application made it big???closed captioning.
Never mind "closed captioning" (which I presume is subtitles for the deaf). In the early 1970s the BBC worked on a complete multipage text information system put in the blanking space; this was announced in October 1972. The system had 999 addressable pages of 40x24 characters, with colour and simple graphics available. Often a single "page" would actually be a cyclic sequence of pages, changing every 20 seconds or so. Subtitles (on page 888) were just one use. http://teletext.mb21.co.uk/gallery/ceefax/ or google "Ceefax" for more information. -- Clive D.W. Feather | If you lie to the compiler, Email: cl...@davros.org | it will get its revenge. Web: http://www.davros.org | - Henry Spencer Mobile: +44 7973 377646 _______________________________________________ LEAPSECS mailing list LEAPSECS@leapsecond.com https://pairlist6.pair.net/mailman/listinfo/leapsecs
