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CRT monitor failing - health risk?

Hi all, Im new here, so apologies if this is the wrong place to be asking this. I have a 19" CRT Sony Trinitron Multiscan E400 monitor. It has been working fine until the last few days, but now all of a sudden the screens brightness seems to be altering by itself (eg dimmer, then lighter) of its own accord. It happens very rarely - maybe once every few hours. I would like to continue using it until it eventually dies, but when googling the problem I came across a poster that seems to have a similar problem here:-

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and one post has me worried:-

"This ain't what you asked, but I'd be concerned... The death of the monitor is NOT your primary concern. CRT monitors are run at about the maximum voltage you can get away with without generating excessive X-rays. If your voltage is normal but dropping as you increase brightness, no problem. But what if it's unregulated and going HIGHER when you turn down the brightness??? That's what happens when the bleeder resistor goes open. Can't tell from your description. But how much risk do you want to take with your eyesight? Where'd I put my flameproof suit??? OK, let me have it... mike"

Now all I really want to know if should I be worried? Could the monitor be emitting x-rays? Or am I save to continue using it?

Thanks in advance

Reply to
raptor9397
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i had a tv that did this, it was the EHT transformer it had a faulty screen pot.

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Reply to
zack

The monitor will shut down if the 2nd anode exceeds a voltage far below what it would take to make xrays come out of the monitor and fry your brain.

Reply to
Meat Plow

Damage to eyesight is not and nowhere near high on the list of ill effects of X-rays.

If you don't expect to spend more than a few hundred hours in front of this monitor before replacing it, I would not worry about it. Otherwise, replacement CRT monitors are cheap now!

- Don Klipstein ( snipped-for-privacy@misty.com)

Reply to
Don Klipstein

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If it is the EHT voltage changing, then the picture SIZE as well as brightness would be affected. Low EHT would give an enlarged, dim picture, whereas higher than normal EHT voltage would give an extra-bright, extra-small picture, and that could increase the x-ray emission, though the glass will have lead in it to provide some shielding. If the picture gets very bright and very small then it might be a good idea to have it repaired rather than continuing to use it. Normally there is circuitry to shut down the monitor if the EHT voltage gets too high, but I suppose that circuitry could also fail, though that would be quite bad luck.

Chris

Reply to
Chris Jones

Thanks everyone for all the replies. At the moment just the brightness of the screen is changing - although one time last week the size did also change whilst the computer was starting up. Im not sure how worried I should be. I emailed Sony customer service who suggested quite arrogantly that the monitor wasnt at fault, and that it would be my PC. They suggested I contacted VIA (my chipset manufacturer) even though I am positive it is the monitor. How much extra X-rays would/could there be? and how much extra risk is it? Im am saving up to buy an LCD at the moment, but until then would like to continue using the CRT.

Reply to
raptor9397

The computer changes video modes when booting up so I would not worry if the picture size changes somewhat during the boot sequence. To be sure that it is not a fault in the monitor related to warming up, you could let the computer boot with the monitor off and then turn the monitor on later when the boot sequence is finished, as a test, to see if the size changes or is permanently too small which might indicate excessive EHT.

If just the brightness is changing and not the size, then that doesn't seem like the EHT is wrong. If that is the case then there shouldn't be extra x-rays.

Chris

Reply to
Chris Jones

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