Discharging CRT anode and capacitors on a VT52 DECscope

From: Tom Jennings <tomj_at_wps.com>
Date: Thu May 27 17:28:51 2004

> On Wed, May 26, 2004 at 11:27:51PM +0000, jpero_at_sympatico.ca wrote:

> > At science museum once saw a very tickish student girl walk off lexan
> > platform by the big sphere HV generator depsite tech's warnings as
> > she stepped off a looong 2 feet long arc... That 2 feet long HV arc must be really packing
> > of power.

Merely in the interests of spawning another near-infinite regress on
electron fundamentals...

NO, it specifically had VERY LITTLE POWER, though a lotta voltage.

        P = E * I

E= voltage, I= Current


Probably as much POWER as a nine-volt battery or two. If it had much
more, it would have been an unsafe display, as it's S.K.O.P. (*) to
either not see, or ignore, or spite, safety warnings, and kid science
museums certainly know that!


* Standard Kid Operating Procedure. I speak from experience. (Hammering
loaded cartridges 1 ohm 1W resistor on car battery cut plugged-in
extention cord w/scissors on a dare (do it quickly) burn worms with 500V
100ft coil wire on car battery fun w/ignition coils fun with Hg fun with
molten metals acids gravity 'parachutes' largest anything smallest
anything smelliest anything crush vacuum tubes under foot surplus photo
chemicals gasoline auto parts tensile strength of treetops...)

tomj


>
> I used to play with those on a regular basis, at COSI, the Science Museum
> in Columbus. Ours was surplussed from Oak Ridge, to read the plate at
> the bottom. In winter, we could reliably get 8" hot blue sparks, or 3'
> wispy sparks. Discharging the ball with your forearm really makes your
> fingers jump. Big fun!
>
> My own Van De Graff generator is much smaller, table-top sized, and has
> difficulty with 2" sparks in the winter. :-(
>
> -ethan
Received on Thu May 27 2004 - 17:28:51 BST