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bz

wrote in
ups.com:

Sam Goldwasser wrote:
"Clyde Crashcup .........................."
writes:
wrote:

I started having trouble with my TV after it was moved in a U-Haul
from San Francisco to Seattle. I managed to locate a faulty solder
joint on the board. Applying pressure to the joint with a strip of
wood fixes the problem.

My problem is this: I am very experienced with electronics and
soldering, but I have little experience when it comes to high
voltage. I need to fix the solder joint but I have no hardware to
properly discharge any high voltage capacitors in the TV.

I think a lot of the reponses so far have been attempts at humour.
Possibly because you say youre very experienced yet dont know how to
discharge a psu cap or the tube eht. No, you cant rely on them to self
discharge over a day or so. Since youre experienced, figure it out.

Go to the library. Get an older copy of the Radio Amateur's Handbook. It
should show you how to make a tool consisting of a wire, a wooden dowel, and
a resistor, that can be used to safely discharge high voltage capacitors.

These devices were called 'crowbars' because that is what they essentially
were, a crowbar with a heavy wire that connected it to ground.

The operator would turn off the power, hang the crowbar on the high voltage
line, grounding it, and work on the equipment, secure and safe. IF someone
accidently turned on the power without removing the crowbar, it would blow
fuses.

Nowdays, a circuit that shorts the output of a power supply to ground in case
of overvoltage output of the supply is called a 'crowbar' circuit, for
reasons that should now be clear.

--
bz 73 de N5BZ k

please pardon my infinite ignorance, the set-of-things-I-do-not-know is an
infinite set.

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