Re: First Light but I have a Problem

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

Original poster: Paul Nicholson <paul-at-abelian.demon.co.uk> 

EMMETT SECREST wrote:

 > The Toroid is now 5" above the top winding of the 4.5" dia.
 > secondary.

 > I am thinking that maybe the Toroid is to large to accomplish
 > breakout given my available power level.

Yes, maybe it is too wide so that it is not protecting the top
of the coil.

 > I was thinking that if it has all that power in the topload but
 > can't breakout from the toroid that it has to go somewhere and
 > thus I get the arcing.

Just like a hydraulic system, the working fluid will burst out at
the weakest point.  In this case the 'working fluid' is electric
charge being forced up the secondary by induction from the primary.
We want it to break out from the topload, but if the top of the
secondary coil is insufficiently protected by the toroid it may
come out there instead.

The presence of the topload close to the top of the coil is
supposed to reduce the field gradient in that area, making it into
a fairly calm and sheltered backwater as far as the electric field
is concerned.

If the toroid is too wide, it will still perform as a topload, but
may not do well with its additional task of protecting the coil top.

 > I tried changing the hieght and the coupling but had the same
 > results without a nail for a breakout point.

 > I am going to make a 13.5" Toroid from the same material tonight
 > and give it a try.

Well worth a try.  The 23" diam version may be just too wide.
You might even try both, stacked - the 23" above the 13.5", for a
large top capacity.  Some people fit a small toroid - a corona
ring - close to the top of the secondary, and this sits inside and
beneath the main toroid.
--
Paul Nicholson,
Manchester, UK
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