Old television danger?

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As a kid I was taught a television still retained energy; even after being unplugged from the power source. I have a 1987 console TV with a nice wood cabinet on a swivel base. I want to remove the innards and make a cabinet for entertainment equipment.
Now, it has NOT been in service for many years and I doubt there is a real shock hazard.
If I did plug the TV back in how long would it take to ensure there was no stored energy? Or am I off base altogether about the energy danger?
Thanks.
-- Oren
"The voices in my head may not be real, but they have some good ideas!"
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Oren wrote:

Two sources of stored charges, big capacitors in the power supply, and the CRT itself which can similarly retain a charge. In most units there are bleeder resistors installed that will drain down the charge within a few minutes. Certainly there is unlikely to be any charge left if the unit has been unplugged overnight. It's mostly an issue for a kid poking around in the TV right after it's been unplugged, or for the service guy working on repairing it and plugging and unplugging it as they work.
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wrote:

The unit has been in a friends storage for any number of years and was given to me. I cannot imagine this thing being hot, now, but I don't know ( my guess).
I was a kid, the last time I poked around in a TV. They had tubes back then :-)) When I removed the back cover and looked inside I thought I better ask here.
-- Oren
"The voices in my head may not be real, but they have some good ideas!"
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Oren wrote:

I'm pretty sure the only tube in a 1987 model will be the CRT itself. At any rate, if it's been unplugged that long there is pretty much no chance anything will still have a charge.
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If there is still power in it after many years, let us all know. I'd like to patent that circuit and get wealthy from the eternal electrical storage cell !

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The older TV sets had two places to mainly store the energy. The picture tube and some capacitors on the board. If it has been a year or more from the last time it was plugged in I doubt it would have any energy left. If in doubt, you can take a screwdriver and hook a wire to it and then to the chassie and put the screwdriver where the wire comes out of the pucture tube side. Just hold on to the handle of the screwdriver.Thre is often a big rubber plug where the wire goes to the picture tube you must get under to get to the connector.
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On Sun, 23 Sep 2007 17:44:07 -0400, "Ralph Mowery"

It has been a number of years since powered. So you mean short the tube to the "chassie" ?
-- Oren
"The voices in my head may not be real, but they have some good ideas!"
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After a few years I doubt it has any stored energy left in it.
Yes, I did mean short the wire comming out the side of the tube to the chassie. The wires at the back of the tube will not have any stored energy in them , but the connection on the side has around 20,000 volts on it when the set is in operation and that is where the voltage is stored.
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On Sun, 23 Sep 2007 14:25:03 -0700, Oren wrote:

Not much to worry but I have seen the picture tube retain and even seemingly recharge on its own after years. Just use your head and keep away from the chassis parts and 2nd anode connector atop the tube and you'll be ok.
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wrote:

Unit has not been powered up in years.
I have a nice magnet :) Will it kill the tube?
Not certain on the "anode" or other parts mentioned (G).
I first figured I could snip the wires connecting all the various parts and then remove the fasteners and gut the cabinet. The tube is connected to the chassis (rubber cap/anode?)...
-- Oren
"The voices in my head may not be real, but they have some good ideas!"
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On Sun, 23 Sep 2007 15:42:25 -0700, Oren wrote:

Yes that is the high volt lead. Take a jumper from the chassis and a long screwdriver with jumper attached and slide it up under the cap to the center where it clips into the tube just to be sure it's discharged. Then clip the wire. You'll be ok otherwise if you use your head, the rest of the wiring is very unlikely to carry any voltages after this time but you can still take a few sensible precautions as I always would. I've replaced quite a few CRTs in my stint at electronics/tv repair years back.
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Meat Plow wrote:

Watch out, dielectric absorption can make the voltage stored in the capacitsnce of the picture tubes anode "come back" by itself after you've shoted it out. Doesn't happen often, but not unheard of.
Best to keep your fingers and such away from the picture tube's anode connector at all times.
Jeff
--
Jeffry Wisnia
(W1BSV + Brass Rat \'57 EE)
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On Sun, 23 Sep 2007 19:46:42 -0400, Jeff Wisnia

Trust Me. I will keep "and such" away :)
-- Oren
"If things get any worse, I'll have to ask you to stop helping me."
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On Sun, 23 Sep 2007 19:46:42 -0400, Jeff Wisnia wrote:

Scroll up in the thread to where I covered this already.
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Danger! Danger, Will Rogers! Danger!
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This should be Will Robinson...to quote the robot!
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wrote:

Thanks to all for posting!
The rubber cap popped off the tube, so I shorted anything I thought would hold power (several times for my sake).
I have the unit gutted and the tube is in the truck ready for a dumpster run. I will break the back nipple off before I toss it in, but I am tempted hear to explosion....
-- Oren
"My doctor says I have a malformed public-duty gland and a natural deficiency in moral fiber, and that I am therefore excused from saving Universes."
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Oren wrote:

NO!
The physics are that you will see an IMplosion.
The broken glass from one side will accelerate toward the center of the tube. By the time the shard moves the ten inches or so, it has reached super-sonic velocity and will keep going until it hits something. You, possibly.
You should have at least 1/8" of steel between you and a disintegrating picture tube.
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wrote:

Toss it into an empty construction dumpster - duck and listen :)
I can't shoot it with a shot gun!
I'll break the tube on the back as mentioned. -- Oren
"If things get any worse, I'll have to ask you to stop helping me."
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If you go to the very back of the tube there will be a very small piece of glass. Take something like wire cutters and cut it off. If done correctly you will hear a lot of air rushing into the tube. Be sure to wear some heavy gloves,glasses/goggles and maybe even a coat. wrap the tube in a blanket. You probably will not need any of this, but it is best to be safe. I have cut off 3 tubes over the years and no problems. Also shot two that were still in the sets with a 22 rifle from about 30 feet. Impressive implosion.
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