# Re: mathematics

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From: 	John H. Couture[SMTP:couturejh-at-worldnet.att-dot-net]
Sent: 	Saturday, September 06, 1997 6:30 PM
To: 	Tesla List
Subject: 	Re: mathematics

At 04:58 AM 9/6/97 +0000, you wrote:
>
>From: 	Kevin[SMTP:wawa-at-spectra-dot-net]
>Sent: 	Friday, September 05, 1997 10:54 PM
>To: 	tesla-at-pupman-dot-com
>Subject: 	mathematics
>
>Now that I have a functioning coil, I would like to begin to read in on
>the theory and especially the mathematics.  Is there a single good book
>that can help me, or maybe a few?  I tried the library but found nothing
>about coils.  I am probably going to try the local university next.
>
>Also, would anyone happen to know a formula for calculating the
>inductance of a choke, taking into account the form shape and size, the
>wire gauge, and the number of turns?
>
>thanks,
>kevin
>
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Kevin -

The mathematical development for TC's almost completely stopped in the
1930's when other high voltage, high frequency devices were invented. Math
developments since that time have been for other types of high voltage
apparatus.

If you are interested in the mathematics of TC's rather than spark length
you are a rare bird. Coilers today depend upon trial and error methods
rather than theory because the theory is little understood. A coiler is
considered advanced based on his experience in building coils rather than on
his knowledge of TC theory.

There are over three dozen fundamental equations that should be solved and
coordinated when designing a TC. The best way to do this is to use a
computer program. The only program presently available that can do this is
the JHCTES Ver 2.3 computer program for Tesla coils. This program uses 46 of
the major TC parameters and coordinates them so the TC is always in tune
when changes are made. The program can do this because it is based on both
theory and empirical data from real coils. However, it does take some time
to study the program to properly use it.

The JHCTES program is for classical coils only because magnifiers, tube,
solid state, etc, types are still in the trial and error stage. Someday a
book and computer program on the design of these devices may become available.

The best way to show the relationships between the parameters of the TC is
with the use of graphs. This requires the collection of data from many
actual coils that have been properly tested. This data must then be
converted into  math equations that a computer can use. This is a
mathematical process using regression methods. If you like math you will
find these math processes very informative. Here again, computer programs
are very helpful. The Tesla coil Design Manual has 26 of these TC graphs.

One of the many advantages of a TC computer program is that you can design
many different types of classical coils without having to actually build
them. You can vary the parameters and the computer will show you how the
other parameters must be changed to keep the TC in tune. It is obvious this
can save a lot of time and money compared to using trial and error methods.
This will give you a good knowledge of TC operation but you will still have
to build coils and learn how to properly test them.

The best way to learn  how a classical TC operates is to develop a
computer program of your own.  This will require building and testing many
different coils to obtain the necessary empirical data that the computer
program would be based upon. Very few coilers have done this so you would be
in a very select group of coilers.

I am sending you some additional information by direct email.

Best of luck with your TC research.

John Couture

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