Re: primary/secondary coupling height ranges

[FutureT-at-aol-dot-com (by way of Terry Fritz <twftesla-at-uswest-dot-net>)]

In a message dated 8/1/00 9:18:11 PM Pacific Daylight Time, tesla-at-pupman-dot-com 
writes:

> Hello,
>  
>  Just for design considerations I'm trying to get an idea of what the
>  "typical" distance might be between the plane of a flat spiral primary and
>  the lowest winding of the secondary.  I was figuring about 1" below the
>  secondary.  I know there is probably much within the design of each coil
>  that would have an affect on this but I am just looking for an "average".
>  Also,
>  what have people heard of others using for the lower and upper extremes.
>  
>  Thanks,
>  John M.

John,

If the primary is spaced far from the secondary such as 2" horizontally,
then, the secondary may need to be lowered so the bottom is beneath
the primary plane.  But if the primary is closer to the secondary such
as 1" spacing, then the secondary may need to be raised a little above
the primary plane.  I've probably gone from 1" below to 1.5" above in
my various coils for the most part.  In general, as the power is 
increased, the secondary may need to be raised to prevent racing
sparks.

Cheers,
John Freau