Re: New Coil: From Scratch

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

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

In a message dated 4/22/01 11:29:02 AM Eastern Daylight Time, 
tesla-at-pupman-dot-com writes:

> 
>  i know some people design their coils around the topload and some have
>  other wyas, but i usually like to start with the secondary. im thinking of
>  something like 8 to 12 inches in diameter. ive seen coils such as terry's
>  10 inche diameter that are wound 10 inches, and some longer. i had thought
>  that the rule of diamter x 4 was pretty good but once again there are so
>  many variences its hard to decide which kinds might be the most
>  successful.

Fox,

I like to base the secondary size on the power input and expected
spark lengths.  For instance if I wanted a 4 foot long sparks, I 
would not use a 10" wide secondary because it would be larger
than needed.  Even such things as the breakrate affect the
needed secondary size.  Low breakrates have a larger bang
size for a given power input and need a larger secondary for
a given spark length, etc.   Also, if I was using a 500 watt
trnsformer, i would not make the secondary 10" diameter, etc.

If the H x D ratio is 4 to 1, or 6 to 1, etc,  this won't really
affect the spark output in most cases.  The spark output
correlates mostly to the input power and break rate in an
optimally designed coil.

I like flat primaries, because they work well, are easy to build
and discourage streamer strikes to the primaary.

John FReau
>