Re: KVA Model 9J

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

Original poster: "Jeff W. Parisse by way of Terry Fritz <twftesla-at-qwest-dot-net>" <jparisse-at-teslacoil-dot-com>

James Cart Wrote:
> > Curiosity is forcing me to ask this dumb question.
> > Umm, which way did the sparks go on an upside
> > down coil? 

Down (up?) at a 45 degree angle towards a fiberglass
and steel "mountain" model.

Terry Fritz Wrote:
> The ceiling was very high compared to the coil and it
> really was sort of in free space.  I don't know if there
> were ever any pictures taken or if Jeff has run the coil
> upside down since...  It had a metal mounting frame and
> drop chains holding it that would probably not be too
> easy to model with E-Tesla6 to predict the arc path...  

Funny you should mention E-Tesla; I used it (and MathCAD
for data visualization) to model and shape the 9J's geometry
(Terry's program creates tables of data that can be viewed
with data visualization software). We compared the plots with
real world observations and made adjustments.

I don't know if we gathered enough data to make any
worthwhile observations. The best upside down
configuration (performance wise) produced the worst
operation in rightside up mode with racing arcs the norm.
We rewound the coil (lower inductance) to give better
rightside up performance (check out Brian Basura in
the Cage 'o Death under Extreme Stunts at
www.teslacoil-dot-com) and can produce solid, lingering,
15 foot power arcs that light up the room (brightness
is the most important TC characteristic in theatrical
applications).

Jeff