Re: Racing arc clues...

["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 5/30/01 3:15:40 PM Eastern Daylight Time, tesla-at-pupman-dot-com 
writes:

> I also know that "over coupling" and "mistuning" are factors.  Are there
>  any other consistent things that have an bearing on this?

Terry,

Also, the addition of a too-large toroid will promote racing sparks,
because the voltage builds up higher before breakout.  As the
power is increased, a coil that did not have racing sparks before,
may develop them due to the larger bang size.  The coupling has
to be backed off at the higher power.
>  
>  Where do racing arcs tend to occur most?  I have often heard near the base
>  of the coil but I think they sometimes appear near the top.  It 3rd
>  harmonics are a factor, that may make some sense.

Mistuning usually causes the racing sparks near the top.  Over-coupling
can cause them mostly near the bottom, sometimes around the middle.
But it can be chaotic at times, with racing sparks appearing almost
anywhere.  Also, any sharp point on the primary, may promote racing
sparks on the secondary at the area that faces the point on the
primary.  In other words, areas of high field stress are more likely
to develop racing sparks.  

Cheers,
John Freau

>  
>  Still many unknowns but looking for more clues...
>  
>  Cheers,
>  
>   Terry
>