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Got shocked by a CRT
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james_s:
I like using a wire with no resistor, the little pop tells you it discharged successfully and gives peace of mind. "Modern" color CRT monitors will self discharge after some time due to the focus divider but monochrome monitors can hold the HV charge for days. The shock is unlikely to harm you but there is significant risk of secondary injury say from dropping the tube so it implodes or yanking your hand back and slicing it open on a sharp edge.
bob91343:
I got zapped by an undischarged CRT many years ago.  It was on my car back seat sitting on its screen, going for a replacement tube.  I opened the car door and grabbed the tube without thought and a spark jumped to my hand.  I was surprised to say the least but luckily didn't drop the tube nor had any adverse effects.
BrokenYugo:

--- Quote from: Benta on January 26, 2021, 08:26:17 pm ---
--- Quote from: james_s on January 26, 2021, 06:26:44 pm ---I've never worn gloves and it's unlikely to stop a discharge from a CRT anode anyway. I just ground a wire to the dag FIRST and then use the wire to ground a screwdriver that I poke under the anode cap. As long as the wire is grounded you can't get a shock.

--- End quote ---

Exactly. That's the "101" part.
The problem is that people who've not dealt with CRTs before think that switching off the thing and discharging the PSU caps is enough.
But the whammo is the anode charge which does not go away when the device is off.

--- End quote ---

Yeah, if not explicitly explained it isn't really apparent that the CRT envelope itself is the HV supply filter cap with 20+kV on it.
andy2000:
For a normal, healthy person, the HV charge on a CRT shouldn't be dangerous, but it's a very unpleasant surprise.  As others have said, just ground a screwdriver to one of the metal straps that touches the outside graphite coating and slip it under the rubber HV cup. 

Even after discharging it, it will pick up a small charge later.  It's not nearly as big as the initial charge, but it's good to be aware of it so you don't drop the CRT if you brush against the HV connector while picking it up.
Halcyon:
The warning labels are there for a reason. Now you know the reason. ;-)
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