On 6/5/2012 2:08 PM, Lloyd Berg N9LB wrote in part:
> I like the direct copper to soil DC contact rather than laying insulated wire
> on/in the ground. Also the solid bare copper wire won't leach away into the
> soil for 40-50 years.
>
> Never bury bare stranded wire because it disintegrates way too fast,
> which is why the National Electrical Code requires that all ground wire
> be solid.
>
>
Lloyd,
I don't think that statement, about you having any benefit of bare
copper in contact with earth, is completely correct. I always thought
the whole purpose of a good ground system under a Marconi type vertical
antenna was to make the currents flow in a highly conductive medium
rather than in a lossy one like soil. (Which varies in conductivity all
over the place.) Under you vertical on 160 is the one place you don't
want your RF return path currents to flow is in a dissipating
diaelectric soil with bare copper wire in contact with it. IMHO the
radial system replaces the lossy medium by replacing it with a highly
conductive medium. Reading the wonderful material from Guy, K2AV, I
think demonstrates that principle, irrespective of the lack of quality
of earth underneath, is found in his FCP counter poise design.
So I would think that insulated wire laying on the ground or just below
the grass is not only the easiest way to go but may also be more
efficient. Laying inexpensive solid or stranded #16 on the grass held
in place by fencing hook or large stapes pounded down in the earth will
bury themselves under the growing grass mat in a few weeks, enough so
that a mower or a string trier will not snag them.
Another issue today is that if copper thieves see bare wire they will
just rip it out of the ground. Insulated #16 stranded is essentially
worthless to them.
Herb, KV4FZ
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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