RE: New Inductance Formula

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

Original poster: "Malcolm Watts by way of Terry Fritz <twftesla-at-qwest-dot-net>" <m.j.watts-at-massey.ac.nz>

Hi Dave,
         Sucker that I am, I tried your formula on two different 
coils and it appeared not to work. Perhaps you would like to show us 
all the fine details of the arithmetic as applied to the following 
helical coils:

Coil 1: 4 turns, radius 13", height 5"

and

Coil 2: 980 turns, radius 4.9", height 45"

I will be happy to furnish the correct answers for inductance as 
measured at DC after seeing your formula applied on-screen.

Regards,
malcolm

On 28 Apr 2002, at 14:57, Tesla list wrote:

> Original poster: "David Thomson by way of Terry Fritz
<twftesla-at-qwest-dot-net>" <dave-at-volantis-dot-org>
> 
> I made a mistake in the previous post.  Pi should be squared.
> 
> Paul,
> 
> Have you actually tried the formula?  What about it is nonsense or crank?
> I'm surprised.  Of all people, I thought you would be the first to try it
> and see what it does.  It wouldn't bother me at all if you could show it
> doesn't work.
> 
> I'm using this formula in real Tesla coil design and it works great.  Humor
> yourself and try it please.
> 
> Here it is again, hopefully in better format...
> 
>                (N * R)^2
> mH = -----------------------------
>      L * c * Cd * 16 * pi^2 *10^-4
> 
> N is the number of turns
> R is the average radius
> L is the length of the wire (not length of the windings)
> c = 2.99 x 10^8
> Cd = 2.112 x 10^-4
> pi = 3.14159
> 
> I have a little more detail on the formula and how Cd was derived at
> http://www.tesla-coil-builder-dot-com/inductance.htm
> 
> Dave
> 
> -----Original Message-----
> From: Tesla list [mailto:tesla-at-pupman-dot-com]
> Sent: Sunday, April 28, 2002 11:11 AM
> To: tesla-at-pupman-dot-com
> Subject: Re: New Inductance Formula
> 
> 
> Original poster: "Paul Nicholson by way of Terry Fritz <twftesla-at-qwest-dot-net>"
> <paul-at-abelian.demon.co.uk>
> 
> Jim wrote:
> 
> > Do ANY of you guys really understand all that???
> 
> Nope.  It's complete nonsense.  Best thing is to ignore crank
> postings.  See the various Tesla related yahoo groups for examples
> of the consequences of not doing so.  Those who enjoy the
> ultimately futile task of refuting pseudoscience will find
> plenty of sport.
> --
> Paul Nicholson
> --
> 
> 
> 
> 
> 
>