Re: Best, easy way to protect NST?

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

Original poster: "Gerry Reynolds" <gerryreynolds-at-earthlink-dot-net> 

Hi Jack,

I just noticed an error in my original post.  The caps I used were 0.0047uf
not 0.047uf.  Anyway, the parts are inexpensive except for the resisters.  I
bought four 500 ohm 50 Watt resisters instead of using the two 1Kohm 100watt
ones.

Good luck,
Gerry R.


 > Original poster: "Jack Vandam" <snotoir7674g-at-mindspring-dot-com>
 >
 > Hi Greg and Gerry,
 >
 > Thanks a lot for the info and schematic links.  That gives me plenty of
info
 > to build the necessary circuit should I decide to.  With what I perceive
as
 > Neon transformers becoming rarer these days without paying much higher
cost,
 > it's probably not going to hurt me to use one of these protection
circuits.
 >
 > Thanks again,
 > Jack
 >
 > ----- Original Message -----
 > From: "Tesla list" <tesla-at-pupman-dot-com>
 > To: <tesla-at-pupman-dot-com>
 > Sent: Tuesday, October 05, 2004 9:36 AM
 > Subject: Re: Best, easy way to protect NST?
 >
 >
 >  > Original poster: "Gerry Reynolds" <gerryreynolds-at-earthlink-dot-net>
 >  >
 >  > I think RF chokes have been shown to cause problems.  You may want to
look
 >  > at the Terry filter instead.  A string of MOV's from each bushing to
NST
 >  > ground (chassis), with a string of caps in parallel with each MOV
string,
 >  > and 1Kohm 100W resister betwen each bushing and the safety gap.  For a
 > 15KV
 >  > NST, use 8 1800V MOVs in a string and 8  0.047uf 1600V caps in a
string.
 >  > Digikey has the parts.  I changed the cap value to 0.047uf from Terry's
 >  > original schematic and increased the number for higher voltage ratings.
 >  > Probably can find a link to Terry's schematic in the archieves that
also
 > has
 >  > digikey part numbers on it.
 >  >
 >  > http://hot-streamer-dot-com/TeslaCoils/Misc/NSTFilt.jpg
 >  >
 >  > Gerry R.
 >  >
 >  >  > Original poster: "Jack Vandam" <snotoir7674g-at-mindspring-dot-com>
 >  >  >
 >  >  > Around the web, I've noticed various coilers placing small, rf
chokes
 > on
 >  > the
 >  >  > output of their neon xformers.  Since I'm throwing together a coil
 > later
 >  >  > this week, I'm curious if there is any specific formula for these
 > chokes
 >  > as
 >  >  > I'd like to add some protection to the NST I'll be using.  Also, how
 >  >  > effective is the protection offered by these chokes?
 >  >  >
 >  >  > Thanks,
 >  >  > Jack
 >  >  >
 >  >  >
 >  >
 >  >
 >
 >