RE: E-Tesla 6.11 strange prediction

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

Original poster: "John H. Couture by way of Terry Fritz <twftesla-at-qwest-dot-net>" <couturejh-at-worldnet.att-dot-net>


Terry -

This is a great triumph for E-Tesla6. The picture is an excellect
illustration of the fields.  It will be interesting to see what Matt's tests
show. This much capacitance reduction is most unexpected. But the unexpected
is the fascination about Tesla coils.

John Couture

-------------------------------

-----Original Message-----
From: Tesla list [mailto:tesla-at-pupman-dot-com]
Sent: Sunday, May 20, 2001 3:42 PM
To: tesla-at-pupman-dot-com
Subject: RE: E-Tesla 6.11 strange prediction


Original poster: "Terry Fritz" <twftesla-at-qwest-dot-net>

Hi John,

I think the 57.3% is indeed correct.  Look at the picture of Matt's coil at:

http://hot-streamer-dot-com/temp/MattD1.gif

The difference between his and most systems is that he has two terminals.

The terminals are right over and under each other.  This vastly reduces
their individucal free space capacitance's since they are right next to
each other.  The energy stored between the two toroids is about zero so the
effective capacitance is far less than if they were significantly far
apart.  This is an advantage of E-Tesla6 in that it figures these nasty
situations out :-))

Hopefully Matt will be able to fine the true frequency so we can see how
close the predictions are.  I am putting my bets on 287253.72 Hz :-))

Cheers,

	Terry


At 01:34 PM 5/20/2001 -0700, you wrote:
>
>Terry, Matt, All -
>
>I did a check on Matt's coil using E-Tesla6 and found the toroid
capacitance
>reduction to be 57.3% compared to the approximate 20% reduction that
>E-Tesla6 showed for other coils. Is this correct?
>
>The basic resonance equation is
>     Fr = 1/(6.283 sqrt(LsCs))
>For Matt's coil Fr = 287730 hz    Ls = 13.76 mh
>
>This gives Cs = 22.24 ph   Cs = Ctor + Ccoil
>
>The Medhurst equation gives Ccoil = 8.14 ph
>for a 2.1 rad and 21.16 Lgt secondary coil.
>The coil self capacity (Ccoil) can also be found with the JHCTES program
>without using calcs.
>
>The effective capacitance of the toroids on the secondary coil is
>     Ceff = Cs - Ccoil  = 22.24 - 8.14 = 14.1 pf (Ceff)
>
>The isotropic (free space) capacitance of the toroids can be found by the
>equations shown on my web site (Secondary Terminal) or by the Sphere/Toroid
>graph I show in my books.
>     Toroid #1  3.25 x 11.25 (OA) = 13.00 pf
>     Toroid #2  4.25 x 18.00 (OA) = 20.00 pf
>     Total isotropic capacitance  = 33.00 pf (Ctot)
>
>The percent of capacitance reduction for the toroids when placed on the the
>secondary coil is
>     % Reduction = (Ctot - Ceff)100/Ctot
>                 = (33.00 - 14.1)100/33.00 = 57.3%
>
>This 57.3% reduction is much greater than the approx 20% found by E-Tesla6
>for other coils.
>
>It will be interesting to see what the actual resonant frequency tests
show.
>There should be two types of res freq tests.
>
>    Test #1  Low test current in sec coil by feeding the coil at the bottom
>with a function generator. The res freq is found with a freq counter.
>
>     Test #2  High current in sec coil by operating TC at high voltage but
>with only corona output. The res freq is determined using a storage scope
>and Terry antenna probe. This res freq should be lower then in Test #1.
>
>Comments welcomed.
>
>John Couture
>
>-------------------------    snip