Bottle Caps, part III

To: "'Tesla List'" <tesla-at-poodle.pupman-dot-com>, "'Tesla List'" <tesla-at-poodle.pupman-dot-com>
Subject: Bottle Caps, part III
From: Tesla List <tesla-at-stic-dot-net>
Date: Thu, 13 Nov 1997 09:32:12 -0600
Approved: tesla-at-stic-dot-net

From:	ghunter-at-mail.enterprise-dot-net [SMTP:ghunter-at-mail.enterprise-dot-net]
Sent:	Wednesday, November 12, 1997 2:28 PM
To:	Tesla List
Subject:	Bottle Caps, part III

I did a third round of experiments with salt water caps based on
750ml wine bottles.  I discovered, quite by accident, the
capacitance meter function on my Fluke 87 multimeter.  I had never 
actually read the instructions before!  Duh!

Based on my earlier series current experiments I had pegged the value 
of a vino bottle at about 1900pF.  The humorless Fluke 87 didn't 
agree.  I wired six caps in parallel and measured their collective
capacitance at .0085uf.  That's an average of 1416pf.  Measured
individually, the bottles ranged from 1290pf to 1460pf.  Not very
uniform.  The ones wraped with aluminum tape gave lower value than
those covered with kitchen foil.  This shows that my "sixpack"
configuration--three parallel caps wired in series with three
parallel caps--will yield only .002uf.  That ain't enuf.  I need
from .0038uf to .0063uf, depending on which design software I choose
to believe (I have four different TC design programs gleaned from
various websites).

So, if I'm using a 15kv/30ma neon xfmr at 50Hz and fixed series
gaps, how much capacitance do I really need?  What would it hurt to
"over cap" the system a little?  It seems like a little too much
capacitance is better than not enough.  A slightly oversize cap will
drop the maximum voltage a little.  So what?  This is easily
corrected for simply by closing the spark gaps a little. The reduced
operating voltage translates into less stress on both the neon
secondary windings and the caps.  Sounds like a "win-win" deal. Is
there a flaw in my reasoning here?

Greg