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Static on TV

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ll_billym | 21:08 Mon 13th Feb 2006 | Science
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This is probably a really stupid question but why is static on a TV screen always black and white, not colour?
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A colour video signal includes a color sync signal which initiates the decoding of the colour demodulation. In the absence of the color sync signal the reciever assumes a black and white format.

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Thank you very much.

Sorry for hijacking your question, but it's kinda related...


Can anyone tell my why, after you've turned your telly off, you can see if glowing for a while afterwards, but only if you kinda look out of the corner of your eye? If you look straight at it, you can't see it, but you can if you look snideily....?

For the same reason that you can't see stars as clearly if you try to look straight at them - its to do with the quantity of light receiving receptors in your eye - there are more in the peripheral vision part of your eye, and more colour receptors in the centre. So when trying to see something that is very dim, it is more visible when you look at it with the corner of your eye than when you look straight at it! Try it one night when looking at the stars and you will see what I mean! Freaky.
Isn't it true that the static IS coloured. Just made up of equal quantities of Red, Green and Blue, which renders it white to the eye!
condiments
Rosyrussel - thanks for that, I'll try it as soon as the clouds lift!
gammaray
If your tv set allows you to observe a very weak colour broadcast you might catch the confetti changing between colour and black & white as the set struggles to process the weak colour sync signal of the broadcast.

Sorry for another hijack attempt, but this is also related. I noticed years ago that the digits on the front of the VCR were jiggling about and I wondered what the hell was going on. I soon realised it was happening because I was eating at the time and when I stopped chewing the digits settled down. Weird! If you haven't noticed this, take a look next time you sit down with a bowl of cornflakes in front of the telly.


I'm still not sure exactly how this is caused - suppose it's something to do with the muscles of the jaw flexing and the movements affecting in the eyes.

...affecting the eyes, not affecting in the eyes!
Your posting in the wrong section pagey. Presumably that is an answer to a question in Food & Drink....!?

lol. No thats what the black and white 'snow' is affectionately called in the industry. Condiments! The summation of 'salt' and 'pepper'.


snook - I don't know if you have ever read an electronic digital display on the front of a bus or coach in your rear view mirror whilst driving - but you get the same effect of it jiggling around. It is an illusion caused by the way the screen refreshes.

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