Re: loop material question
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The higher in frequency you go, the more you need ribbon conductors to deal with monsterous currents line lightning strikes.? The reactance does not change.? Its reactance can easily be calculated using:
????????? X(L) = 2 x pi x f x L
pi = 3.14159 f = frequency in Hz L = Inductance in H
Both the ribbon and cylindrical conductors exhibit inductive reactance.? For a unit length of each the wide ribbon conductor exhibits less inductance than the cylindrical conductor.? As the reactance increases (wire is worse than ribbon conductors) AND the frequency increases,? the copper ribbon and the cylindrical conductor become less and less capable of handling very large currents.
Dave - W?LEV
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Back when I was working with several radio sites, we were using 2" wide flat copper ground strap; because it was supposedly lower impedance than wire ground conductors. [Lightening as you know is NOT a DC impulse.] Mmmm. At what frequencies do flat strap conductors stop being lower impedance than round conductors or vice-versa?
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On the other hand, flat strap in the open air outdoors would tend to flap and twist in the wind, making it unsuitable for an outdoors antenna.
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Phil, K0TWA
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