[LEAPSECS] Celebrating the new year a few seconds late

Clive D.W. Feather clive at davros.org
Sat Jan 5 18:10:16 EST 2019


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: clive at davros.org     | it will get its revenge.
Web: http://www.davros.org  |   - Henry Spencer
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