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Date: Fri, 11 May 2007 17:26:03 +0200
To: rsgb_lf_group@blacksheep.org
From: Rik Strobbe <rik.strobbe@fys.kuleuven.be>
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Message-Id: <20070511152356.309162E68CC@smtps01>
Subject: Re: LF: ERP spreadsheet for loops
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Hi Alan,

just one more remark:
The formula used assumes a constant current for the entire loop, what 
is valid only for small loops (compared to the wavelength).
In one article I found that the upper limit was a loop circumference 
of lambda/5, thus 120 m at 500 kHz.
So at the height of 10 m the length should be no more than 50 m (@ 500 kHz).

73, Rik  ON7YD

At 15:26 11/05/2007, you wrote:
>Hi all, another whoopsie !! As a result of the sudden interst in loops and
>thanks to help from Rik, we spotted an error in the loop Rrad calculation (I
>thought it looked a bit small !) It transpired I was using the 136kHz
>wavelength as a constant when I imported the equation from another sheet,
>and I did not consider anyone using loops on 500k at the time so did not
>check the results. I hope I didn't disuade anyone building a 500kHz loop. At
>least the loop v Marconi "L" comparison is correct now. The new sheets have
>been uploaded and have two lines of correction declared, above the
>descriptive text.
>http://www.btinternet.com/~alan.melia/programs.htm
>Make sure you hit REFRESH as some browsers seem not to see new content with
>the old file name. The file names have been kept the same to link with other
>pages.
>
>Cheers de Alan G3NYK


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