Re: The weakest link??

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

Original poster: "by way of Terry Fritz <twftesla-at-qwest-dot-net>" <FutureT-at-aol-dot-com>

In a message dated 3/24/02 4:29:36 PM Eastern Standard Time, tesla-at-pupman-dot-com 
writes:

Jim,

Overall construction looks good.  A 9/30 NST can do only
so much.  I use the equation:

  spark length (inches) = 2.2*sqrt NST rated VA

So that comes to 36" spark length.  But my present 9/30 NST coil
(the TT-32), gives a little less spark length than that because
the toroid is a little too small at 3" x 10".  I'm getting at least
33" though, probably more.  I forget what spark length you said
you got?  Did you try putting a break out point or rod on the
toroid to help the spark break out?  Often that's needed if the
gap is limiting the coil's output. The TCBOR gap may limit the spark
length because it often has to be set for a very narrow gap spacing
for smooth operation.  Such a narrow spacing reduces the output of 
the coil drastically.  This is why sync rotaries, and STSG's give such
strong performance.  The output voltage is not limited by any
gap spacing.  Of course such operation stresses the NST more,
but no problems have been reported by those who use these
systems.  Gary Lau gets good results with his single Vortex
gap, and others have used the design with similar results.  I think
his gap spacing is about 3/8" for a 60/15 NST.  It's a good idea
to clean the pipes in the TCBOR gap from time to time, because
they can build up an oxide which severly reduces the performance.
Sandpaper is good for the cleaning operation.  Your cap is probably
still OK.  Sometimes when the NST gets hot, the performance
drops.  It may be stronger the next day after it cools.  I generally
shut down for the day when the NST feels too hot.  NST's can't
take all that much.  Sometimes the initial testing and setup of
the coil destroys the NST.  But usually not if you're careful enough
(read experienced enough   :)   If you obtained only one or two
streamers from the small toroid without a breakout point, then
it was large enough for the system as it is.  Now if you upgrade
the gap or something to make the coil more powerful, then you
may need the larger toroid (if you don't need it already).  I have
to give rather general comments to try to cover various situations.

Cheers,
John