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Re: ISEF display
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> 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 :-)
>