RE: Mutual inductance and K factor

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

Original poster: "Terry Fritz" <twftesla-at-qwest-dot-net>

Hi John,

I trust you are familiar with the actual measurment since I think it
basically comes from you book :-))

The computer calculation is actually from Dr. Rzeszotarski.  The file and
an explanation are at:

http://hot-streamer-dot-com/TeslaCoils/Programs/MANDKV31.PDF
http://hot-streamer-dot-com/TeslaCoils/Programs/MANDKV31.ZIP

Paul Nicholson also computes coupling to a high accuracy for his TSSP
project.  Paul's source code is available (UNIX) for those that wish to
dive into it.

http://www.abelian.demon.co.uk/tssp/

Cheers,

	Terry

At 04:40 PM 10/24/2001 -0700, you wrote:
>
>Weazle -
>
>Thank you for sending me the test data from your coil. I am aware of Terry's
>method for finding the mutual inductance but I am not very familiar with the
>typical calculations. My notes on his method are buried somewhere in moving
>boxes and I do not have his address for the test.
>
>Your caculations appear to be incorrect in that the mutual inductance should
>reduce instead of increase when the secondary is raised. Also, are your
>coils pri to sec distance (1.0) and the pri inside radius (3.05) and outside
>radius (7.55) of the used turns agreeing with the program outputs? I hope
>that you can soon test your coil with my method which requires no
>calculations by the user. With the proper amps (2.65 or 3.18) in the ammeter
>you only have to read the mutual inductance uh from the DVM meter.
>
>The program shows a mutual inductance of 83.57 uh (you show 32.36) for zero
>inches distance of the sec above the pri and 66.15 uh (you show 42.97) for
>1.0 " distance. The 32.36 to 42.97 should be a decrease not an increase in
>mutual inductance. The K Factor of .075 to .100 should also be a decrease.
>
>If Terry would give me the address for his method I can determine what the
>calcs should be. Thanks Terry.
>
>John Couture
>
>---------------------------