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by analog31 306 days ago
Beware. I took a poke from the focus anode of a CRT when I had a job repairing mainframe terminals in the early 80s. I thought I had discharged it, but apparently I didn't.

I had to sit down in a quiet room for the rest of the work day, before I could function again. It was probably 13 kV, which was typical for monochrome displays back in the day.

Also, anything in a CRT television can kill you because TV's tended to have a "hot" chassis. The repairmen always plugged a TV into an isolation transformer so they could ground its chassis while working on it. There's a lot of counterintuitive things about those old electronics due to clever cost reductions.

1 comments

The focus anode is lower voltage (~1kV) but its supply may be capable of higher current.
I might have gotten my terms mixed up, but it's the suction cup thingy on the side of the tube. And it was disconnected, so the poke I got was from the charge built up on the capacitance.

We had a procedure for discharging it, which I must have bungled.