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-   -   Discharging TV (http://www.videokarma.org/showthread.php?t=261261)

boboh1 04-08-2014 01:55 PM

Discharging TV
 
Will be starting to recap a couple of TVs. What is the best method to make certain the TV is discharged? I was thinking of taking the high voltage lead then touching it to the HV cage along with placing high watt resistor across the can capacitor leads. What do you guys think is best?:headscrat

Username1 04-08-2014 02:03 PM

Caps most likely will be discharged after a day of being off...

Picture tube jumper lead from a screw driver to HV cage, push the screw driver under the hv attachment on the tube....

boboh1 04-08-2014 03:26 PM

Perfect. Thanks for the info.:thmbsp:

Electronic M 04-08-2014 05:19 PM

I recommend clipping the CRT anode button to ground, after discharging with a jumpered screwdriver and removing the HV wire from the tube. Or inserting a high value resistor in series with the jumpered screwdriver. Otherwise the CRT anode can 'recover' it's charge and bite you again in a few moments after it has been discharged.

I learned this the hard way on a Silvertone with a 21GUP22 CRT several years ago.

N2IXK 04-08-2014 06:03 PM

Yes, the CRT is actually a very high grade low-leakage glass dielectric capacitor. Think really big Leyden Jar.

In a dry environment, they tend to "self charge" due to dielectric absorption.

boboh1 04-08-2014 09:01 PM

Good to know. I will certainly do that.

Jon A. 04-10-2014 09:30 AM

So, no voltage at the CRT pins but there is at the evac stem? Last tube I aired, after doing so I reached out to grab a piece of dangling glass and a spark jumped to my finger. Not a shock per se, but I could feel it and yanked my hand back mighty quick.


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