Re: Cap Size

> Stephen, 
>         Hi, I would like to make a sugestion on your toroid. Get some 4 inch
> dryer duct (3 inch if your secondary is 4 inches or smaller)and make up one
> with aluminum tape, experiment with the diameter. I think you will find that
> it will improve your performance

Great suggestion, but I would take it a step further and suggest that you
buy a few pieces of duct, make up a number of toroids of varying sizes and
just play with them to see what works best.  We were messing around with
my old 4" diameter, 11" long cardboard secondary in a primary that was
really designed for a 6" secondary, and just by top-loading it with (at
one point) a rounded metal water pitcher and two other 4" toroids (the
small coil itself was dwarfed by the top capacitance), I was able to get
16" arcs. Without all the loading, I was getting substantially less.
You're going to get your longest sparks when you have yur coil loaded to
the point where the sparks just break out, and that's as much a function
of the avalilable input power as the input voltage.  Also, the lower tune
allows you to use more turns on your primary and couple more energy into
the secondary.  It seems that as long as you have the power to pump into
it, top-loading is really a win-win situation (but then Richard Hull has
been saying that for years now).

Steve Roys