Got my first "bite" from a monitor last night..

GoneMad

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Got my first "bite" from a monitor last night..

I pulled the chassis out of my 27" inch Neo Geo last night and replace some caps. I discharged it like I usually do and do it again 5 minutes later. When I get the anode cap off, I always run it directly on the chassis a couple times as well. I removed the chassis, replaced the caps and pit it back in the frame. As I was trying to fit the anode back into the hole, "ZAP". WTF, DAMMIT, F&%k, OUCH!! In my finger and I felt it on the tip of my tongue and arc to one of my fillings it felt like. Who knew? Even AFTER a cap kit and the careful discharging, it built up another charge. I guess you can never get too comfortable at this.
 
Towelie says, "don't forget to ground that bitch out several times with 30-second pause in between until you fail to see a spark."

"...You wanna get high?"


And even then you could still get a residual shock. Luckily raster monitors are much more forgiving than vectors.

Could have been worse, try getting a love tap from 20-something amps of 3-phase 480VAC. That will put you on the ground in convulsions, assuming it doesn't kill you.
 
My worst Zap was when I was plumbing. We were putting a new adapter on a well casing 6 feet down. We had a welder there as well. He left the rod (arc welder) on the top of the hole. I reached up for a wrench and got the tip on the inside of the elbow. That was not fun.
 
The discharge comes from the tube. If I get a spark on discharge, I don't disconnect the anode cap. Leave it sit, take a 5 minute break, discharge again. Repeat process if you get another spark.

I only ever remove the anode cap after attempts at discharge do NOT result in an audible spark.
 
I pulled the chassis out of my 27" inch Neo Geo last night and replace some caps. I discharged it like I usually do and do it again 5 minutes later. When I get the anode cap off, I always run it directly on the chassis a couple times as well. I removed the chassis, replaced the caps and pit it back in the frame. As I was trying to fit the anode back into the hole, "ZAP". WTF, DAMMIT, F&%k, OUCH!! In my finger and I felt it on the tip of my tongue and arc to one of my fillings it felt like. Who knew? Even AFTER a cap kit and the careful discharging, it built up another charge. I guess you can never get too comfortable at this.

It is not uncommon for a tube to re-build a charge while sitting. I usually discharge the tube again before I go to put the anode cap back on.
 
It's far faster and safer to just clip the discharge wire to the dag strap and jam the screwdriver under the anode cap leaving it touching the anode clip. Leave it there for a minute while you do other things and that will discharge more than the "zap, wait 5 mins, zap, wait 5 mins, zap..." routine; and faster too.

The intent is to remove the entire charge from the tube...NOT to see how many sparks you can get.

If you tried to discharge a 9V battery---would you quickly short it out 10 separate times over 10 minutes or simply leave something across both terminals for a single period of time instead? Which do you think would still leave more power in the battery?

Yeah you don't get visual confirmation of discharge but it will discharge.

And ALWAYS re-discharge before moving the tube or reattaching the anode clip as it can build up a charge in-between times.
 
Dont any of you use gloves?? I always use leather welding gloves when i mess with monitor..

No. 25KV won't even notice those gloves are there...

It is not uncommon for a tube to re-build a charge while sitting. I usually discharge the tube again before I go to put the anode cap back on.

I just use a wire with clips at both ends. One to the dag wire, the other to a screwdriver. I discharge, then unclip from the screwdriver and clip the anode hole (the "ultor", IIRC). That dag-> anode jumper stays there until I reconnect the anode.
 
Could have been worse, try getting a love tap from 20-something amps of 3-phase 480VAC. That will put you on the ground in convulsions, assuming it doesn't kill you.

A dear friend of mine lost her dad to one of those. He was working on a center pivot irrigation system. He thought the power was off and it was not. By the time anyone figured out what happened it was too late.


Fortunately, monitors are much more forgiving than that. I failed to discharge a tube that I thought the chassis was not charging, due to the lack of a raster. What I did not realize that it was going into some sort of fail-safe mode and was in fact briefly powering the tube. Long enough, in fact to light me up real well when I made the surprising discovery.

The best thing to do is dishcarge the tube again just before connecting the annode. Or you might be able to make it so that your screwdriver (or whatever you are using) stays in the hole on the tube and the discharge path stays intact until you are ready to reinstall the chassis.
 
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It is not uncommon for a tube to re-build a charge while sitting.

You guys aren't doing this correctly.
The tube and the inner and outer coatings on it form a capacitor which stores this charge.
You're effectively shorting the two plates together by shorting out the anode hole, but the glass tube is the dielectric material in this capacitor. It holds the electric energy inside of the physical structure of the glass. You can disturb this structure and assist in removing the charge by striking the glass tube with the handle of a screwdriver while shorting the lead to the frame.

It's like 'shaking' the charge out of the glass.
 
You guys aren't doing this correctly.
The tube and the inner and outer coatings on it form a capacitor which stores this charge.
You're effectively shorting the two plates together by shorting out the anode hole, but the glass tube is the dielectric material in this capacitor. It holds the electric energy inside of the physical structure of the glass. You can disturb this structure and assist in removing the charge by striking the glass tube with the handle of a screwdriver while shorting the lead to the frame.

It's like 'shaking' the charge out of the glass.

I don't know I've never had any problems and I never had to strike the glass tube with a screwdriver.

I think I will stick with discharging before removing the anode cap and before re-installing the anode cap.
 
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