Re: Tesla Coil toroid Size

To: tesla-at-pupman-dot-com
Subject: Re: Tesla Coil toroid Size
From: "Malcolm Watts" <MALCOLM-at-directorate.wnp.ac.nz> (by way of Terry Fritz <terryf-at-verinet-dot-com>)
Date: Tue, 08 Sep 1998 19:50:38 -0600
Approved: terryf-at-verinet-dot-com

Yesterday I wrote:

<snip>
>      Here are some figures for some different coils I have measured. 
> These figures are not the last word because isolation was not as 
> great as I would have liked for definitive measurements, but here 
> goes:
> 
> Terminal 1  (fairly large, toroidal profile, no centre hole)
> Terminal 2  (smaller, same shape)
> Terminal 3  (much smaller, same shape)
> 
> Dsec    Hsec     Csec     Cterm1    Cterm2     Cterm3
> 
> 3.5"    14"     6.4pF     39.4pF    29.3pF     18.5pF
> 4.4"    17.2"   7.9pF     36.2pF    26.6pF     16.2pF
> 4.8"    21.8"   9.4pF     31.6pF    22.7pF     13.4pF
> 6"      22.7"   10.7pF    33.3pF    23.8pF     13.8pF
> 6.7"    12.1"   8.4pF     40.2pF    29.7pF     18.4pF 
> 6.7"    19.8"   10.3pF    38.4pF    27.9pF     16.9pF 
> 6.7"    32.3"   13.5pF    34.1pF    24.2pF     13.8pF
> 9"      16.1"   11.2pF    31.7pF    22.8pF     13.6pF
> 16.7"   39"     22.9pF    30.1pF    21pF       11.9pF

<snip>

Terminal sizes are:

#1 :  11" high (thick), 30" diameter
#2 :  10"     "       , 23"    "
#3 :  6"      "       , 19"    "

As far as I've been able to ascertain through other measurements, the 
fact that there is no hole in the "donut" does not significantly 
alter capacitance. Imagine e-field lines stretching from the various 
parts of the terminals to ground and you might see a reason why a 
filled-in top doesn't make a difference. For the meaurements above, 
the terminals were all at roughly the same distance from floor/roof 
of the garage so the resonators were mounted at different heights.

Malcolm