[TriLUG] Tesla coil (was: Re: GoDaddy CEO shoots elephant...)

[Peter Neilson]

On 04/02/2011 09:01 PM, Phillip Rhodes wrote:

> You had me at Tesla Coil!  Any excuse to build a big ass Tesla Coil works
> for me...

At one time, in the smelly, distant past, around 1968, the Boston, 
Massachusetts Museum of Science owned and operated a rotary-gap Tesla 
coil that had been built by a gentleman in Connecticut. He gave it to 
the museum because it kept punching holds in the roof of his garage.

I ran it once a day during the brief time I worked for the Museum. No 
one knew what frequency band it worked in, but because we kept it down 
to about 15 seconds of operation (on fear the gap would melt) the FCC 
never caught us transmitting A0, which as far as I know was then and is 
now totally illegal. http://en.wikipedia.org/wiki/Spark-gap_transmitter

I think it had four turns of copper-strap primary, about about 3000 
turns of enameled #20 secondary, and ran the gap off a neon-sign 
transformer. I do not know what it used for a capacitor, perhaps 
aluminum foil and window glass. All very low-tech high-tech.

You could build one easily, given only time and gumption.

The Museum also had a Jacob's Ladder demonstration (another high-voltage 
transformer powered it), and of course the giant Van de Graaff 
electrostatic machine that is now the highlight of their Elihu Thompson 
Theatre of Electricity. At that time it was a piece of unrestored junk 
and was never fired up when I was there.

http://en.wikipedia.org/wiki/Spark_gap#Visual_entertainment
http://en.wikipedia.org/wiki/Van_de_Graaff_generator

The wikipedia entry for Tesla coils indicates that the building of 
spark-gap Tesla devices is a fluorishing and dangerous hobby. Tesla 
himself is an additional hobby, attracting the interest of genuine 
scientists:
http://www.teslasociety.com/corum.htm
http://www.scribd.com/doc/2887582/Ball-Lightining-Teslas-Production-of-Electric-Fireballs
and of crackpots.

Whether or not Tesla was himself a crackpot, he surely is a magnet for 
them. Beware of whom you befriend in Tesla fandom. (For fun, I just 
dipped my toes gingerly into the internet's vast sea of crackpot 
mathematics, and observed that the Fermat, Tesla, angle-trisector and 
anti-Goedel people are busy accusing each other of stealing their bogus 
and incomprehensible ideas.)