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Re: Introduction

>>From jim.fosse-at-bdt-dot-com Fri Mar  8 01:23 MST 1996
<snip>
>	if you have a choice, pick the 0.03" polyethylene. use 3
>layers, between plates. Here in US 0.060 cost $21 for a 4' by 8'
>sheet, 0.030" 2 * $12.95 for a 4' by 8' sheet. The 2 0.030" sheets
>will get 1 cap with 0.090 dielectric and good for about 20KV RMS RF!
>For the $5 extra, build in the extra margin. I've run my TC for about
>1 hour total now on my 0.060" cap. without blowing it. This weekend
>I'll build a 0.090" (3 0.030" layers) cap.
>
>		jim
>
Hello Tom, Jim and others,
        I built a parallel plate capacitor using .090" of polyethylene in
the form of three .030" stacked sheets between each aluminum flashing
conductor.  I have it immersed in mineral oil.  It has held up well to two
15kV 30 mA neons in parallel.  There tend to be microscopic imperfections in
the plastic which cause it to fail.  By using three sheets, you reduce the
liklihood of having the imperfections line up.  The other thing I did in
constructing the beast was to leave 1" margins on three sides: 12" x 10"
flashing, 12" x 12" plates.  Each aluminum sheet sticks out 1".  I then ran
three brass screws through each aluminum end sheet with washers between
layers so that the aluminum would lay flat.  I tightened it down and
attached my heavy wire leads to the brass bolts.  It works MUCH better than
the barium titanate caps I started with, and has held up well to
considerable torture.  It is considerably below par compared to my new
Condenser Products cap, however.
Regards,
Masrk S. Rzeszotarski, Ph.D.