Re: Please help with capacitor

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: dhmccauley-at-spacecatlighting-dot-com 

I might have to disagree.  Richard Hull was using rolled poly caps in many
of his magnifier coils which I have seen in a few of his videos.
He was using these with both 14.4kV and 34.5kV potential transformers.  I
believe he used two of these caps in series for an equi-drive type
system for use with his magnifiers.

Dan


 > A home made cap used with a 15kV power supply must be made from at least 2
 > or 3 individual caps, in series.  A single
 > cap will fail due to corona at the edges of the foil.  I spend a huge
 > amount of effort on two attempts at rolled poly caps.  The first used a
 > single layer of 40 mil poly, and dies after a few minutes.  The 2nd
attempt
 > was made with two units in series, each with a single layer of 40 mil
 > poly.  It too died after several minutes (see
 > http://www.laushaus-dot-com/tesla/rolledcap.htm).
 >
 > Assuming you are using 60 Hz power, your cap is mains-resonant with the
 > NST, and this is a bad thing.  In addition to being healthier for the cap,
 > I have found that a value of about 2X the mains-resonant value gives the
 > best performance with a static gap.
 >
 > Regards, Gary Lau
 > MA, USA


 > I'm making a new flat plate capacitor for use with my 15,000 volt 60 ma
 > NST. I'm using aluminum foil plates 7.5"x9" (67.5 sq. in.) with 30 mil
 > polyethelyne (6 layers of 5 mil each) between each plate. Using the
formula
 > C=kA/d (k=2 ) I get 3.25 sq. meters or 74 plates, does this sound right?
My
 > last capacitor had only 30 plates. I'm aiming for .013 microfarads.. is
 > this right? Using different programs I get different values of capacitor
to
 > use.
 >
 >
 >
 >
 >