Re: More information on Nightmare Mikes 90kV/270mA Tesla Coil

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: DRIEBEN-at-midsouth.rr-dot-com 

Hi all,

I'd have to third that! Some kind of definitive proof of these claims
would be nice. It would really be hard to build a primary circuit
that could hold off >90kV w/out serious corona/flashover problems.
I have a 140 kVp, 500 mA x-ray tranny that I power my big Jacob's
ladder with and the rails are set at 7 1/2" apart at their arc start-
ing point (their closest approach to each other) and it will self
start with the variac turned up to only just a little over half of
the rated 240 volt input. It seems to me that you would have to enclose
the entire primary circuit within a sealed atmosphere of pressurized
inert gas at several atmospheres of pressure to make this approach
practical.

I've done some testing and it seems that x-ray transformers are rated
according to the output voltage being under the loading of the x-ray
tube head, so the actual output voltage of an open circuit secondary
from an x-ray tranny is probably more than the rated voltage at the
rated current. I checked my x-ray tranny and determined that it should
theoretically put out about 180 kV with 240 volt input. Of course, the
insulation would probably fail pretty quickly if ran in this manner.
One definite no-no for x-ray trannies is to run them open circuit on
the secondary outputs with the full rated primary input voltage and I
have toasted a few of them in this manner before myself!

David Rieben

PS - I heard of someone from the Art Linkletter Show that stole about 3 pole
pigs from the local utility company, in Missouri, I think, that was try-
ing to built some kind of time machine. That wouldn't be you, would it
"Nightmare" Mike?

----- Original Message -----
From: Tesla list <tesla-at-pupman-dot-com>
Date: Sunday, January 4, 2004 9:29 am
Subject: More information on Nightmare Mikes 90kV/270mA Tesla Coil

 > Original poster: dhmccauley-at-spacecatlighting-dot-com
 >
 > > On another subject, you previously posted (10-4-03) some
 > information on a
 > > Tesla coil you had made using a 90kV, 270ma  X-ray transformer
 > charging a
 > > bank of five-hundred (500) Cornell Dubilier model 943
 > capacitors (5
 > strings
 > > of 100 capacitors). I am unaware of anyone else ever
 > successfully using
 > 90kV
 > > in a Tesla coil tank circuit, and would be very interested if
 > you could
 > > provide a detailed description of the entire system, its
 > performance and
 > the
 > > types of problems you encountered during debugging this system.
 > Of course,
 > a
 > > few photographs would be worth a lot of verbiage.
 > >
 > > Regards,
 > > Scott Hanson
 >
 > Yes, I second that.  Mike has stated that he has done quite a
 > large number
 > of "hardcore" tesla projects including
 > many giant pole transformer jacob's ladders, massive coin shrinkers,
 > including the 24kW, 90kV/270mA X-Ray powered
 > tesla coil.  So far, all I've seen is a lot of talk, but no photos or
 > detailed descriptions on performance, problems, and
 > lessons learned etc...  I am very interested in seeing some more
 > informationregarding these projects and definitely some
 > pictures especially the x-ray powered tesla coil and descriptions
 > on what
 > your 100kV+ spark gap looks like, how you
 > solved your corona problems on the primary circuit, etc...
 >
 > I know that Terry does have public space available on the
 > www.hot-streamer-dot-com website for some photos etc...
 >
 > Please post some!!!
 >
 > Thanks
 > Dan
 >
 >
 >