Re: Medhurst

Terry, Ralph, All

I was wondering if anyone has derived a more physical relationship of the
data and what it is based on? 

Has anyone found the physical basis of the data?

I have found that the relationship is very highly correlated with the surface
area to volume ratio. The linear correlation coefficient of the H
factor/surface area ratio versus the L/D value is 0.989. 

If anyone is interested, I would be happy to send them my documentation. 

I am hoping to have my web page up soon, but if anyone would like to post the
documents for the interim I would be grateful.

Bryan Kaufman

Tesla List wrote:
> Original Poster: Terry Fritz <twftesla-at-uswest-dot-net>
> Hi Ralph,
> The original papers are reprinted in "Wireless Engineer", February and
> March of 1947 if you can find it.  They have only been out of print for 1/2
> a century :-)  There is also a follow up letter in the "Correspondence"
> section of the June issue.
> Medhurst worked from the earlier attempts by Butterworth, Nagaoka and
> Palerimo and made many very high precision measurements and corrected the
> earlier works.  The equations are based on curve fitting from a large
> number of measurements thus there is no real "derivation".  The papers
> mostly dwell on earlier work and the pains they went through to make the
> accurate measurements with the tools of the day.  The older experimenters
> tried to base the capacitance on the turn to turn capacitance or even the
> wire length :-o  Medhurst found that the physical dimensions of the coil in
> space are what really defined Cself...
> The original table from the March issue of the paper reprint is at:
> www.peakpeak-dot-com/~terryf/tesla/misc/Medhurst.jpg
> This is the table all the other equations are based on...
> Cheers,
>         Terry
> At 02:41 PM 7/10/99 -0400, you wrote:
> >Hi all,
> >
> >Would someone kindly show me the oft-mentioned Medhurst equation and its
> >derivation?
> >Is there a text reference to it that is not out of print for a century?
> >
> >Cheerful thanks,
> >Ralph Zekelman
> >

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