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Re: ISEF display

Perhaps I should clarify my intentions.  This coil's primary purpose is to
attract
attention.
I mainly wanted to demonstrate the "skin effect" as it is an integral part of
my
project.  Even if that is not possible, a Tesla coil would still attract
attention.;)

    I had planed to build a faraday cage around it and surround that with
Plexiglas.  That is intended to cut down on noise (both RF and sound) and to
keep
anyone from getting shocked. If anyone has any suggestions on improving this,
please e-mail me.  Thanks.


Jeremy :-)

Tesla List wrote:

> Original Poster: forlaser-at-gte-dot-net
>
> before you go and build this puppy, you better be certain you will be alowed
to
> use it. From what I remember of the ISEF rules (I did the science fair thing
> back some years ago) you cant use more than about 20v, unless it's properly
> insulated per some national code. I'm not sure what code would say about
> insulating a 200,000 volt source of harmonic rich AC, but i'm sure the safety
> inspector at the fair will raise an eyebrow from the neon sign transformer,
let
> alone the coil. Another part of the rules included a clause that said there
can
> be nothing distracting or offensive. even a small coil makes a heck of a lot
of
> noise, so you might get complaints there. Also coils through off ALOT or RF
> interference. An ISEF has one of the highest 'packing desnities' for
electonic
> and computer gear I've ever seen outside of an electronic and computer gear
> trade show. You might run into problems there to... I don't want to be a
stick
> in the mud, but I just thought I should let you know about potential
problenms
> you may have...
> Pyroguy
>
> Tesla List wrote:
>
> > Original Poster: "Jim Lux" <jimlux-at-jpl.nasa.gov>
> >
> > ----------
> > > From: Tesla List <tesla-at-pupman-dot-com>
> > > To: tesla-at-pupman-dot-com
> > > Subject: ISEF display
> > > Date: Sunday, March 28, 1999 6:18 PM
> > >
> > > Original Poster: jeremy sweeney <cyberjer-at-inetone-dot-net>
> > >
> > > Greetings,
> > >
> > >     I qualified this weekend to go to the 1999 ISEF.  Part of my project
> > > involved a Tesla Coil, so I wanted to build a small one for my display.
> > I
> > > have built small and large TCs before, but this one will be a little
> > > different than I am used to.  Since putting a grounding rod into the
> > floor is
> > > not an option, is there some way I can do a virtual RF ground?
> >
> > For a small coil, a metal sheet on the table top or hardware cloth or
> > chicken wire (aviary netting) should work. If it extends about as far out
> > as the coil is tall, it should work just fine (i.e. a 1 ft high coil in the
> > middle of a 2 ft diameter plate would work). BTW, I've run a 2' high coil
> > off a 30 mA NST with no grounding other than the third wire with reasonably
> > good results.
> >
> >   Also, I'm not
> > > going to have a lot of free time between now and then, so any
> > recommendations
> > > for some really cheap capacitor sources?
> >
> > 1) Surplus, obviously
> > 2) doorknob caps... 40 kV at 2700 pF is a commonly available value, and a
> > pair will get you just where you need to be. About $20 each at the higher
> > priced surplus places. Or, brand new from RF Parts in San Marcos CA...
> >
> >   I'm going to use a 15 kV 30 ma NST
> > > and a 5.31 nF cap.  Thanks.
> > Built one at that size in a day about a year and a half ago. Two 2700 pF
> > doorknobs, dryer duct/pie pan top load, about 10 turns in a pancake coil of
> > 1/4" copper tubing, secondary was 2 ft long on 4" pvc pipe with #20 ga (?)
> > wire and a double static gap using 1" copper pipe chunks about 2" long and
> > a muffin fan blowing through the gap. Works like a champ... Noisier than
> > all get out...
> >
> > >
> > >
> > > Jeremy :-)
> > >