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Richard Casady Richard Casady is offline
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First recorded activity by BoatBanter: May 2007
Posts: 2,587
Default Capacitors for RF ground

On Thu, 12 Feb 2009 13:32:02 +0000, Larry wrote:

(Richard Casady) wrote in
:

When I was a kid we had an electrolytic, rather three in the same can.
We paralleled them, twisted three wires together solder, repeat.
We would charge it up with a 90 volt battery and kill guppies. The
leads were 3/4 in apart and we would straddle the fish with the leads.
Also blew holes in aluminum foil. I caught a friend of my kid brother
about to put the leads in a wall socket. Should have let him do it.

Casady



I had a massive, high-current electrolytic with battery-sized ears sticking
out the top of it to connect to bus bars....a real brute. It was something
like 1.2 Farads at 250 volts, but I can't remember exactly. It's very
unusual for that voltage to be so much capacitance.

Charging it up to 200 volts took many minutes as the power supplies
available had limited current capabilities. Once charge, this beast was
straight from hell. Discharging it across a steel bar welded it solid to
the bar with a bang that could empty the electronics shop...(c;]


That is less than 300 joules. My twelve pack sized photographic flash
has 1200 joules. Discharges in 1/400 sec, a time film likes.
250 volts is in the ballpark.

Casady