Re: First light for an old coiler

["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 11/14/01 9:50:10 AM Eastern Standard Time, 
tesla-at-pupman-dot-com writes:

Dave,

You're using a resonant sized capacitor, so you have to be
very careful.  Your safety gap at 1" is kind of wide.  Folks
will tell you the static gap should be set at the distance it
will fire with nothing else connected to the NST.  However,
such an adjustment will severely limit your spark length when
using a resonant value cap.  To get the max spark length
from a resonant coil with the SRSG, you'll need to use a 
rather wide safety gap setting of at least 7/8", despite the
danger to the NST that that represents.  This is why the use
of an LTR value cap is recommended.  In any case, first of all,
the total gap spacing at the SRSG should be set very narrow,
at about 1/16" or less.  Otherwise, the combination of the wide
static gap setting, and the wide SRSG spacing will quickly 
destroy the NST's.  It's very easy for the SRSG to fail to fire;
it needs a narrow gap spacing.  It's important to phase up the system
at low power, and never run it out of phase at high power.
When all is set correctly, the safety gap should *never* fire. 

It's much safer for the NSTs to use an LTR cap of at least
double the capacitance value you're using.  I used to use
a resonant cap with a sync gap, and I had no problems, but
some other folks did.

Your coil should be capable of rather long sparks of at least
7 or 8 feet.  

Cheers,
John
-

> Follow up to my previous posting. As you may recall from my earlier post the
>  16 inch high test secondary was severely over-coupled leading to serious
>  dancing arcs across the surface of the secondary. Happily the 36 inch
>  secondary coil in exactly the same configuration shows none of this
>  behavior. With no tuning or adjustment I achieved 21 inch arcs to a 
grounded
>  object and 12 inch breakout was seen on the toroid. I am hoping to double
>  this with tuning and higher power settings.