Re: Secondary size

To: tesla-at-pupman-dot-com
Subject: Re: Secondary size
From: Hollmike-at-aol-dot-com (by way of Terry Fritz <terryf-at-verinet-dot-com>)
Date: Wed, 21 Oct 1998 23:27:41 -0600
Approved: terryf-at-verinet-dot-com

In a message dated 10/20/98 4:59:47 PM Mountain Daylight Time,
tesla-at-pupman-dot-com writes:

> 
>    Mike -
>  
>    You are correct in that the maximum inductance for the TC secondary coil
>  has a 10/9 ratio of radius to winding length with a fixed wire length. You
>  can find this inductance quickly with the JHCTES computer program. The
>  program will also indicate this ratio has two undesireable characteristics,
>  a high volts per turn and a short winding length that could cause
>  flashovers. With the program you can change the inputs to eliminate these
>  unwanted conditions.
> 
  Perhaps if someone were attempting to build a coil to receive the energy
from a TC from across the room or so,  this would be a good design as you
would not need to attain such a high voltage gradient.

>    You asked if anyone has built a coil with a high radius to winding length
>  ratio like Tesla's Colorado Springs coil. This was done by Robert Golka in
>  the 1970's. He told me he got 50 foot output sparks using 150 KW. I did not
>  ask him if these were controlled sparks!
>  
>    The JHCTES does not cover such large coils, but as a test of the program
>  I show a JHCTES printout in the Tesla Coil Notebook of a coil this size but
>  using instead only 60 KW. The secondary coil is 50 feet in diameter by 8
>  feet high with a 6.25/1 ratio of radius to winding length. The program
>  showed a spark length of 37 feet. The numbers appear to be in the ballpark.
>  
>    John Couture
>  
>  
  I was actually thinking more in the range of 1 to 10 kW input power, but
thanks for the input just the same.  It would be nice to have the facility and
resources to make such a large coil :)
Mike