[Prev][Next][Index][Thread]

Cap setup suggestions needed





From: 	Brandon Doughan[SMTP:fiveht-at-well-dot-com]
Sent: 	Wednesday, June 18, 1997 9:48 AM
To: 	tesla-at-pupman-dot-com
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!