Re: Coil design questions.

On Wed, 2 Dec 1998, Tesla List wrote:

> Original Poster: "D.C. Cox" <DR.RESONANCE-at-next-wave-dot-net> 
> to: Travis
> The 60 ma drive current will give you much better performance as the cap
> won't be starving for recharge current.  If you have to stick with the 30
> ma drive, then reduce your cap to around .005 or .006 MFD and use primary
> turns on your primary inductor to acheive resonance.  At the 6 inch dia I
> would strongly suggest a flat spiral primary as an inverted cone would
> begin to produce overcoupling and forced resonance which can lead to
> problems especially with neon sign transformer (NST) powered systems.  If
> you have the means to check the coeff. of coupling shoot for a value
> between 0.18 and 0.20 which seems to work very well with small and medium
> size systems.

Thanks for the responce. After more reading I was beginning to think the
flat primary would be a better choice. I can probably get more
transformers, the shops arround here are kind of a pain but it's worth it.
How much current does a 15KV/30ma neon pull anyway? I want to make sure I
don't burn up the varriac. :)

I probably can't check coupling, I'm not sure how I would go about that.
Is there a coupling meter? ;) How about an equation?