Re: Shockers...

["Donald E. Simanek" <dsimanek@eagle.lhup.edu>]

On Wed, 12 Feb 1997, Dwight K. Souder wrote:

> 	Greetings everyone!  A student asked me a question that I wasn't
> sure of, so I thought I'd pose the question to the rest of you.  One of
> my students was asking about a practical joke device that looks like a
> regular book, but when you open it, it gives the holder a jolt.

Get friendly with an amateur magician, or stop by a magic store, or
consult a catalog of magician's apparatus (Magic, Inc. in Chicago,
Tannen's in NYC, Daytona Magic, in Florida...) This can be accomplished
just as certain other shocking devices. Yes, as you say, it could just be
a vibrator like the "joy buzzer". However, there also cute devices selling
for about $20 which are a miniature vegas style slot machine, with the
three whirling wheels with symbols on them, and a lever on the right you
pull down to make them spin. Mine is about 5 inches high by 3 inches wide
by 2 inches deep, and uses one 1.5 volt battery. Inside is a cute
miniature tesla coil, activated when the lever is pulled. The lever and
the case of the device is metal, so you get a very hefty shock when you
pull the lever. One of my victims was so startled he dropped the device on
the floor involuntarily. It still works.

I would not recommend you pull these jokes on people with heart problems.
Try it on yourself first, if you are tempted to buy one. However, its
probably one of the least expensive small Tesla coils you can buy for
physics experimental demos.

The one I got stopped working (after a few days). A look inside showed
that it had been badly assembled, and the spring which forces electrical
contact with the metal case had slipped out of position. Easily fixed.

Your book would have to have metalic covers if it were to work with this
device.

> 	I'm not sure what he's talking about (yes, I live a sheltered
> life), but my guess is that it is either a "joy-buzzer" device which
> doesn't really shock but vibrates or something that has a capacitor in
> it.
> 	Does anyone know how these books work?  If it is a capacitor,
> isn't it dangerous to use such a device?  I know the capacitors in tvs
> and some old radios have enough "juice" in them to melt a screwdriver
> when placed over the terminals...yes, I know from experience when I was a
> kid.  :-)  What type of capacitor is being used?

Mine has a physically small and rather ordinary capacitor of the
radio-type. It merely stabilizes the frequency. Remember, these are AC
output (DC input) devices, the high voltage, low current, AC output being
the result of a high turns-ratio transformer.

> 	Hmmm...maybe I should attach a few of these to the magazines I
> see kids hiding behind their textbooks, when they should be studying. 
> > :->
>
> Dwight

As to safety, I'd rate them in the same category as the Van de Graff,
but somewhoat more painful and 'shocking'. In these times, with lawyers
panting for personal injury business, I'd say you'd best avoid using any
of these with students in the classroom or lab. Use them on yourself, or
on a willing faculty colleague who has signed a legally binding waiver.

The situation is murky. Electrical devices of many types are sold for
medical purposes, muscle relaxation, pain reduction, etc. There are
devices like TENS units and "violet wands" being widely used for sex-play
and sexual stimulation. The main hazard of the latter is that it can
actually burn the skin if carelessly used, and it also emits ultraviolet
light. (So I'm told.)

As you said, you live a sheltered life. So do I. :-)

	-- Donald

......................................................................
Dr. Donald E. Simanek                            Office: 717-893-2079
Prof. of Physics                    Internet: dsimanek@eagle.lhup.edu
Lock Haven University, Lock Haven, PA. 17745          CIS: 73147,2166 
Home page: http://www.lhup.edu/~dsimanek            FAX: 717-893-2047
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