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Another way to detect current on the outside of coax is to run your hand up and down the coax wile an analyzer is connected , if you see a fluctuation on the meter then current is following on the outside. On vhf I built sleeve chokes to remove it with great results. KC5ULU


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If by improving conductivity, you mean flooding several acres or square miles with ocean (or saltier) sea water (or via natural intrusion near a low lying shoreline or wetlands), or installing a solid copper floor several square wavelengths in size in the parking lot, yes. But some people have reported improved antenna performance by putting a metal mesh of ...


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Below for some perspective on this topic is a NEC4.2 analysis showing the difference in performance of a 40m, 1/4-wavelength, unloaded, base-fed vertical monopole antenna system when driven against either a 5/8" OD or a 12" OD, copper-clad, 8-ft long ground rod buried in poor Earth (1 mS/m, d.c. 5). Increasing the ground rod OD up to 12" is ...


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A dipole antenna does not require a connection to an "r-f ground" reference, either in the form of a ground rod or a set of buried radials. Its radiation efficiency typically is ~95% or more without it. OTOH, a vertical monopole does require a path to an r-f ground reference, because that path provides the 2nd terminal of the antenna system, which ...


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Surely a 1m copper stake provides better ground connectivity for a vertical dipole? What really matters is conductivity. Current doesn't just go in the ground rod and then it's done. It has to flow through the surrounding soil. Soil isn't a very good conductor: (68.2 kΩ, says the display) Now imagine how much lower this resistance would be with a copper ...


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The purpose of the ground radials isn’t to ground the counterpoise. The purpose of a dense field of radials is to emulate as much as possible a perfect mirror surface, so that, to the far field, the vertical monopole seems to have a mirror image half that makes the monopole seem more like a full size vertical dipole, with a pattern maxima orthogonal to the ...


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Because the radials act as ground, and they're better at it than actual ground. Ground (as in: dirt) isn't a great conductor. A couple laid out good conductors hence work much better as ground plane than well-connected earth. For RF, a good connection to ground potential isn't necessary – what's necessary is that there's a large plane that conducts.


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