Re: 16" coil

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

Original poster: "Area31 Research Facility by way of Terry Fritz <twftesla-at-uswest-dot-net>" <rwstephens-at-hurontario-dot-net>

That large sized resonator would be happy being driven at 10 kVA+ power levels
from a pole pig if wound with #16- #18 AWG , plastic covered wire with a toroid
in the ballpark of 60- 70 inch major diameter and 15 " cross section while
hurling hot streamers in excess of 13 feet long.  However by using your small
NST will not achieve breakout without a breakout point.  I question why you
want to build such a large resonator for such a low powered coil.
 
If this is a resonator destined to be a 'bigger' system someday, you may wish
to try a toroid made from 3" aluminum flex-duct perhaps up to 24 inches in
major diameter for the NST application.  Your sparklength will probably be in
the 20" range.
 
You could place the large toroid previously mentioned on this resonator, but
assuming you would be able to achieve system resonance with a modest sized tank
capacitor that your NST will be able to charge, and this suggests a high turns
number primary coil, you will run into an issue of corona leakage from myriad
imperfections and micropoints on your topload that will bleed energy faster
than the topload can build and store it.  The surface quality of the large
topload would have to be considerably smoother that one normally needs.  That
is difficult to achieve in a home-made topload.  After all this expense and
effort you'd still need a breakout point, or perhaps a small discharger
terminal about 2-3 inches diameter sticking a couple of feet above the massive
toroid on a conductive rod.  Your sparklength still wouldn't be much more than
about 20".  As someone else replied to your query, it is power not the size of
the coil that will determine the sparklengh (generalization).
 
You said you were wondering.  Wondering is good!
 
Robert W. Stephens
Director
AREA31 Research Facility
AREA31 Radio Observatory
Co-curator
Hangar31 Vintage TV Museum
<http://www.area31-dot-org>www.area31-dot-org
 
>
> ----- Original Message ----- 
> From: <mailto:tesla-at-pupman-dot-com>Tesla list 
> To: <mailto:tesla-at-pupman-dot-com>tesla-at-pupman-dot-com 
> Sent: Friday, January 26, 2001 00:00
> Subject: 16" coil
>
> Original poster: "by way of Terry Fritz
> <<mailto:twftesla-at-uswest-dot-net>twftesla-at-uswest-dot-net>"
> <<mailto:Gbjsjg-at-aol-dot-com>Gbjsjg-at-aol-dot-com>
>
> I'm building a 16" diameter 64" length coil 15kv 30ma and I'm wondering how 
> big my toroid has to be?
>                                                                 -Thanks Max 
> Joseph
>
>