Years ago, when I trained in electronics, we were warned about CRTs storing huge charges for years. Does anyone know if modern CRTs are now designed to dissipate this charge when the unit is turned off?
by 
Nulinvoid
ANSWERS: 8
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I wouldn't assume it. Always test circuits before beginning "derprobispoken".
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"NO"
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This question is irrelevant. ALWAYS assume that the thing is charged unless/until you verify that it has been discharged. If you didn't see it discharged, discharge it again just in case. You don't know how long it's been sitting there. You don't know it's particular design. And unless you have a strict tag-out program, you have no way of verifying that other people have discharged it.
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Always treat anything electronic or electrical as though it is fully powered up and working. Remember it is the componant that you assume is dead that will nail you. Severe injury and or even death can result from high voltage hits. So be careful!
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it only takes a screwdriver and a clip lead to discharge it, don't take chances. Why do you think they call it a flyback? Because thats what will happen to you if you touch the output...
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Wrong People. The CRT will not hold a charge. (Electrons flowing through a vacuum dissipate quickly.) It's the large capacitor connected near the CRT that holds the charge. And yes, they can hold a charge for days ... weeks, but I have not heard of holding a charge for years. It would have to be a good size cap to hold a charge for a year of more.
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Years ago the CRT's did not have bleed resistors to drain the potential fatal charge. All the new CRT's I have seen employ bleed resistors to prevent shocks when repairing un-powered CRTs
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The CRT is in effect a large capacitor and will hold a charge for some time. I cannot tell you how long but it is often for days to weeks. Regardless use proper safety precautions when removing the anode cap from the CRT. Most sets even today will hold the charge in the CRT and also in other capacitors and areas of the set. Take a refresher course at your local community college in electronics servicing.
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