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To: rsgb_lf_group@blacksheep.org
Subject: Re: LF: more acurate formula for ground loss
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From: "john sexton" <computernetworks@excite.com>
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<br />
Hi Sasha,
<br />
Putting in the same antenna details as before, the new formula gives 38 ohms, still too low by a factor of over 2, but much better than with the first formula.
<br />
However in order to do this since my earth wires are actually buried I used a value of h = .0005 (1mm diam. wire) the minimum value permitted with your formula. Since H >> h, the reduced formula is appropriate, but that is very sensitive to the value of h when h is small, so I think the result I obtained is pretty meaningless. Also my ground mat consists of many wires, in many directions, together with 4 or 5 ground rods of 2 metre length.
<br />
To assume that H << L (1?) is also not appropriate, since that would be a vertical with a small top hat.
<br />

<br />
One problem with your email, which perhaps you can please clarify, both lower case L(l) and the number 1 (one) look exactly the same. Is the length of the horizontal part L or One? Is the counterpoise length L or One?
<br />

<br />
Great to see you are still working on this formula.
<br />
73, John, G4CNN
<br />

<br />

<br />
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