# T.C. design

• To: tesla
• Subject: T.C. design
• From: chip (Chip Atkinson)
• Date: Mon, 28 Nov 1994 17:40:08 +0700

```Greetings,

Could someone offer some pointers on Tesla coil design? I am mainly concerned
with two topics: design sequence, and performance enhancing techniques.
The design sequence that I plan on taking is geared towards using the materials
at hand.  The performance enhancing techniques are things to consider when
designing the coil.  That being said, here's what I am planning on doing:

Coil design:
Given a bunch of 22 ga. magnet wire and a 4" thin wall PVC pipe for
a form, design a coil that works well.  I plan on figuring out
if the wire diameter will allow between 400 and 1000 turns and
produce a coil with a height to width ratio of about 4:1.
Then, calculate this length, and figure out the 1/4 wave frequency
based on this length.  Given the frequency, coil size, and number
of turns, find the inductance.  Then calculate the capacitance
that is needed to make the LC secondary circuit oscillate at the
desired frequency.  Then, once I have the secondary designed,
design the primary coil so that it is about 3x the diameter of the
secondary coil.  Figure out the size of the capacitor that I need
based on the size of the primary coil and my transformer output.

Now the question:  Does anyone who has successfully designed a tesla
coil see any problems with this approach?

Performance:
I frequently read that the old coil designs are less efficient than
the modern ones.  The question is why?  Is it strictly the materials,
or is it some choice bits of knowledge such as "don't make your
coil over 4 times taller than it is wide".  I would appreciate it if
secondary system designs.  I figure that I can get the spark gaps
figured out later, though that may not be a good idea:  perhaps a
coil system is also designed around a specific type of spark gap.

Background info:  I built a working 3" dia. tesla coil from the TCBA news.
It works great, but now I want to go to something slightly bigger that I
designed by myself.
I can use the design programs, but I would like to know how to do it first.

Any and all comments are appreciated.

Chip
before I use a "crutch".

```