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From: "Ashlock,William" <William.Ashlock@edwards.boc.com>
To: rsgb_lf_group@blacksheep.org
Subject: LF: RE: transmitting loops
Date: Fri, 29 Mar 2002 12:28:45 -0500
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Hi Rik,

>I am trying to find out is how one can calculate the loop
>inductance of a big transmitting loop (based on the dimensions).
>I found 2 formulas for the calculation of a 1 turn coil, but both mention
>the dimensions in cm, so I don't know if they are usable for big loops.

>Does someone has a formula that has proven to be usable for big loops?

I use the formulas for inductance found in the loop section all late
editions of the ARRL Antenna Books (too hairy to show here; the formula
<G>), and it IS in cm. The accuracy is fairly close to my measured values.
For example, I calculate 109uh for a #12 (2mm) square loop having 50'x 50'
dimensions. The third term in the formulas will turn out to be insignificant
for loops this big. 

I also checked this formula against my 1/2" 50' x 50' cooper pipe loop
inductance and it came out close to the measured 84uh.       
 
Bill A

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