Re: Testing Bottle caps???

To: tesla-at-pupman-dot-com
Subject: Re: Testing Bottle caps???
From: "Gregory R. Hunter" <ghunter-at-accucomm-dot-net> (by way of Terry Fritz <twftesla-at-uswest-dot-net>)
Date: Thu, 19 Aug 1999 22:40:35 -0600
Approved: twftesla-at-uswest-dot-net
Delivered-To: fixup-tesla-at-pupman-dot-com-at-fixme

Albert,

The best place to test a Tesla coil capacitor is in a Tesla coil!  I don't
recommend testing them with just an NST.  This is an invitation to 60Hz (or
50Hz) resonance and the resulting unwanted, evil, and destructive
consequences including ruined NST and fractured bottles.  Besides,
out-of-circuit testing doesn't prove very much.

If you insist on testing your caps in this manner, put a spark gap in
parallel with the bottle cap and set it quite narrow--no more than 0.25"
The spark gap will bang away like a little 60Hz machine gun.  This is very
hard on caps & NST.

As for your appropriate calculated values, you can estimate 750-900pF for
each 12oz (330ml) beer or wine cooler bottle.  A cluster of twelve, 12oz
bottles is a good match for your 15KV/60ma NST.  A 750ml wine bottle is
good for about 1200-1400pF, so eight of them would be a good cap size for
your NST.  These approximate values are close enough to allow you to make a
reasonable guess about which primary tap to try first.  I say go ahead and
build the Tesla coil & "test" your bottle caps there.

Best Regards,

Greg

At 07:21 PM 08/18/1999 -0600, you wrote:
>Original Poster: "Albert Race" <race-at-dgms-dot-com> 
>
>
>Another question...
>How should I test the bottle capacitors once I have the "appropriate
>calculated values" I am using a 15000v 60mA NST. Should these capacitors be
>in parallel with the output of the NST terminals? and the spack gap running
>in series from one terminal to the other? a diagram would be helpful. also,
>I haven't started building anything yet. I am starting out with the
>capacitance (TC) in order to understand it better(functionality) after I get
>the calculated capacitance values, I will then construct the other portions
>of the circuit. probably secondary first.
>
>thank you...
>
>Albert
>
>
>
>