Re: arc length/secondary length and magnifier questions

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

Original poster: "B2 by way of Terry Fritz <twftesla-at-qwest-dot-net>" <bensonbd-at-boo-dot-net>

Hi Jimmy:

> how can a tesla coil make an arc that is longer than the distance between the
> toroid and strike rail? i read that the coil nemesis could make 14 foot arcs
> with a 48" tall secondary. i also saw that richard hulls magnifier could make
> 10 foot arcs when the extra coil is only 3"x12

> JImmy

     I've witnessed Richard Hull's "Magnifier" in operation several times.
It did break down between the top and bottom toroids every great once in a
while.  It never tracked the little "extra" or "tertiary" coil.  The design
achieved near-perfect electric field control.  The electric field along the
"extra" coil must have been nearly parallel to its surface by virture of
the two big toroids.  Additional control was provided by the "safety gap"
between the overhanging toroids.  The wire was also well insulated with
"Kynar".

     As to why two-coil systems achieve spark lengths greater than the
length of the secondary, this is a question for which I also seek an
answer.  The work of Felsenthol & Proud (sp?) gives some hints.  The
wonderful experiments alluded to by DC Cox, in his earlier catalogs, also
give interesting data.

Cheers,
Barry