Voltage Doubler Cap Size?

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Original poster: "Winston Krutsch by way of Terry Fritz <twftesla-at-qwest-dot-net>" <u236-at-earthlink-dot-net>

Hi All,

	In experimenting with voltage doubling arrangements with various xfmrs,
I've come to wonder what the "ideal" cap size for this purpose is.  With
MOTs, it appears to be as big a cap as you can get ;-)).  I've put 2.4
uF caps in my dual MOT voltage doubler, and the output arc is vicious
;-)).  The transformers get very hot, very fast, but it could be done in
theory.

	I want to make a voltage doubler for my H&R 2700 VAC 330mA units, but
don't know what size to use, nor how to calculate it.  In my attempts to
calculate this, I get about 0.5 uF, but I'm not sure about that.  Can
someone help me figure this out the "correct" way???

Thanks,
Winston K.

PS-My tests with the H&R xfmrs indicate that they want more than 0.3 uF,
since when I increase the size in 0.1 uF increments, the output gets
hotter/nastier, and the distance the arc wil jump remains about the
same.  I haven't got any more caps to continue, though.  Could I have
possibly found the correct value (0.5 uF) all by myself
mathematically??? ;-))