In article ,
Johnny B Good wrote:
Hum bars would have only become apparent with the advent of colour TV
broadcasting which started mid 1967 in the UK. Prior to that, the
monochrome broadcasts (both 405 and 625 line) were locked to the
national grid.

Not so. They went off mains lock some time before colour. I think it may
have been not long after BBC2 started.

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*I see you've set aside this special time to humiliate yourself in public

Dave Plowman London SW
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