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(God I love his hair)
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The whole video signal is designed to convince an old magnetically-deflected picture tube to display something resembling the image that the camera sees. Most of the funny timing relates to the fact that the horizontal and vertical deflection coils are inductors, and so take some time to kick the electron beam from one end of the screen back to the other end.
The front and back porches are times at each end of a horizontal scan line (15.75 kHz) when the electron beam is āturning aroundā to travel quickly from the right edge back to the left edge to begin another scan line. This is time that no picture information can be displayed.
The vertical timing is shown as .05V +.03V/-.00V. That means that out of each 60 Hz video field, from 5-8% of the time is spent waiting for the beam to be deflected from the bottom back to the top of the screen. In later years, they put the closed-caption text data in the video signal during this time period, since itās not visible on the screen. Although if you get an old TV and turn down the vertical size, you can see some twiddling horizontal stripes at the top of the screen, which is this data.
(I spent a good bit of the 1980s designing video generation systems for early computers, and I built a couple weird TV sets five years ago: SatanVision and the Video Coat.)
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My MIL retired her 1970ās B&W telly only when the BBC quit broadcasting an analogue signal. She has not replaced it.
Apparently, the licence information used to come in large print, with additional unrelated flyers containing news useful to pensioners.
I have a black and white Predicta here, just because I like to look at it. I donāt fire it up very often because the VHS is a couple of yards away, and because I donāt think the flyback transformer will last very long. Those are the weak link in any Predicta. I wanted one of these from the first moment I saw one. I may have watched J-MEN FOREVER on it once, just for the experience, or maybe I just intended to. This set had a flyback go bad once before. You can tell from the dot in the center of the picture tube where the phosphors burned out from having the beam stay pointed at the one spot for too long. The guy I bought it from probably bought another Predicta just for that transformer. (This part of the comment doesnāt relate to you, Punchcard. I stuck it here, along with the third paragraph, because the blog software tactfully suggested that one long post is better than three short ones. The third para was originally a reply to ontopic.)
Archive.org has a carload of old radio shows that are worth listening to, like Lux Radio Theater and the Mercury Theater. The comedy shows have the same ratio of crap to good stuff as current TV. Great for driving. I used to listen to Nero Wolfe or Phillip Marlowe when I had a half-hour daily commute, or Iād put Jean Shepherd on. Orson Welles did a seven-part version of āLes Miserablesā that livened up a cross-country trip last month.
Iām still waiting for the Usenet guy who enters any discussion of television with the information that he got rid of his TV in 1985. Iām afraid he may have died. (Oh, and it was a black and white set. Heād have wanted me to mention that.)
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Seconded!
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Apparently hundreds of thousands of UK residents are prosecuted every year for not having a license (http://www.wigantoday.net/news/local/tv-licence-fines-branded-unfair-1-7386890), so the licensing authority is obviously doing more than sending out letters.
Sometimes they communicate with the courts to arrange prosecutions, on the basis that if you donāt have a licence you must be lying about not having a TV, if the experience of acquaintances is anything to go by. It certainly seems to be an uphill struggle to convince them that the reason one doesnāt have a licence is because one has no TV, has no interest in TV, and will likely never own one.
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