Re: Test Cap, dry/oil (fwd)

From: 	Peter Electric[SMTP:elekessy-at-macquarie.matra-dot-com.au]
Reply To: 	elekessy-at-macquarie.matra-dot-com.au
Sent: 	Saturday, December 20, 1997 5:05 AM
To: 	Tesla List
Subject: 	Re: Test Cap, dry/oil (fwd)

Tesla List wrote:

> ---------- Forwarded message ----------
> Date: Thu, 18 Dec 1997 06:30:07 -0700
> From: Scott Stephens <stephens-at-enteract-dot-com>
> To: Tesla List <tesla-at-pupman-dot-com>
> Subject: Re: Test Cap, dry/oil (fwd)
> At 08:19 AM 12/15/97 -0700, you wrote:
> >I have had an idea about this for some time that seems to have been
> born
> >
> >out by Gary's experiment. If you have an air space cap, it will have
> a
> >lot of air between the plates causing a fair bit of looseness between
> >plates. When you measure its capacitance with a small applied
> voltage,
> >the plates will be at a certain spacing and you will get a certain
> >reading. At a higher applied voltage you will get a higher reading as
> >electrostatic attraction will cause the plates to be closer together.
> >
> >Under normal TC operating conditions, this cap will have a small
> range
> >of capacitance value rather than a single value and should have a
> less
> >sharply defined tune point on the primary. This may be the cause of
> the
> >cap heating and lack of energy in the sparks that Gary describes.
> Adding
> >
> >oil on the other hand will do a lot to "stiffen up" the cap. This may
> >also be why commercial caps seem to perform slightly better than our
> >home made jobs. It might be worth doing some experiments with flat
> plate
> >
> >caps held very tightly in metal frames.
> >
> >What do you think?
> It's easy to forget the electric and magnetic fields are FORCE fields.
> Only
> at very high power, and in very dense materials, does the force
> perceptibly
> manifest itself.
> Using super energy-density materials like ferrites and piezo-ceramics
> (with
> Mu0 and E0's in the 1000's) requires ultrasonic-acoustic
> considerations, or
> you end up with heated scrap.

If you think you need very high power, I invite you to try an

Build a rolled poly cap (the value is not too important) and before you
immerse it in oil, charge it up with a few hundred volts. Hang on to it
tightly with your hands (ensuring you have several layers of insulation
for protection) and discharge it through a short circuit.


Peter E.