Cap setup suggestions needed
From: Brandon Doughan[SMTP:fiveht-at-well-dot-com]
Sent: Wednesday, June 18, 1997 9:48 AM
Subject: Cap setup suggestions needed
Hey you HV freaks-
I was lucky enough to get ahold of 20 or so doorknob caps rated
at 30KV and 3600 pF (.0036MFD). I'm wondering about a few things:
Firstly, they are paired and incased in rubber blocks with three HV
leads, coming of each end and in the middle. [they are from a HV
multiplier device]. On one end of the cap pairs (I've scrapped the
rubber off a few) there is a resistor. I don't know the value. My
question is, if I use several pair in a coil powered by a 15KV NST, how
will these resistors affect my capacitance? It would be nice to keep
the added insulation of the rubber (and not have to scrap all of it
off!), but if the resistance is negatively affecting my coil output, as I
suspect, then I'm gonna have to do it.
Second question- I know you want to have your caps rated 3
times your primary voltage, but I want to get away with just have my 30KV
caps with my 15 KV NST. Anyone have experience with doorknob cap
failure? Think I can do it?
Last question- I cracked one of these caps open and found that
it consists of just two plates each no more than 3 sq. ins. and about an
inch of that strange ceramic dielectric. How do these get .0036MFD??
This must be because of the K value of that stuff. This amazes me.
Thanks for your help_ Brandon
PS- Visit the High Voltage Camp at Burningman '97!