Re: Toroid or sphere?

["Albert Hassick" <uncadoc-at-xxxxxxxx> (by way of Terry Fritz <twftesla-at-xxxxxxxxxx>)]

Hi John, Terry, All.  I am no expert in the field and I can only state
what we have observed with our coils which were fitted with round
toploads. Yeah, the arcs do seem to have a tendency to want to go upward
when you use a sphere or ball topload. This we have noticed when using
our 8" foil covered ball atop our coil.  A steel trailer hitching ball
atop our coils also gives out a mostly vertical arc pattern.  We will get
three or four big streamers at first which circle around the sphere.  And
the longer we run the coil, the stronger and thicker the arc becomes near
the top of the sphere as more and more of the energy applies itself to
the very top, as if creating a heated ion channel similar to a chimney
effect. The main arc will form at a crinkle in the foil tape, and no
matter which way we place the sphere, it will always try to find a arc
path nearly straight up from one of these tape crinkles.   What is scary
is when a person approaches the ball topped coil and then the arcs come
down and try to strike horizontally as if they were seeking a humanoid
ground terminal, the arcs then seem to lengthen just to try to strike the
'humanoid'.  So something about our bodies when we approach the coil must
present a nifty target for the Tesla!  Human grounding rod? Iron in our
hemoglobin?  H2O and salt in our bodies acting as a conducting medium?   
Are we nothing more than walking and talking capacitors?  What an enigma!
 Al.

On Tue, 21 Nov 2000 22:33:21 -0700 "Tesla list" <tesla-at-pupman-dot-com>
writes:
> Original poster: Terry Fritz <twftesla-at-uswest-dot-net>
> 
> Hi John,
> 
> At 02:39 PM 11/21/2000 -0500, John Freau wrote:
> snip...
> >
> >Ball electrode can form straight single streamers that come
> >straight off the top of the ball at times, if the ball, and other
> >conditions are right.  Toroids throw the sparks outwards.
> >
> 
> At first, I was confused by this.  But I remember seeing pictures of 
> Duane
> Bylund's coils where streamers are indeed coming straight up from 
> ball
> electrods.  I ran a stress model:
> 
> http://hot-streamer-dot-com/TeslaCoils/Temp/sphere.gif
> 
> That shows the field stress is apparently a tiny bit less right at 
> the top
> of a sphere (I wonder if the stres model is introducing an error 
> along the
> center??).  However that is not the full story.  I think, much like 
> a
> Jacob's ladder, the heat from a streamer goes up and guides the 
> streamer to
> a path directly above the terminal.  I think people have mentioned 
> that the
> streamers off spheres tend to go outward but sometimes will change 
> to a
> straight up streamer after running a bit which would support this 
> idea.
> 
> FWIW...
> 
> Cheers,
> 
> 	Terry
>  
> 
> 
>