A ham can certainly try a voltage fed 180 degree vertical, but the
physical conditions at the feedpoint change dramatically because it's
quite possible a few KV of RF v. will be there, unlike what we have
with a current maxima at the feedpoint. So insulation and keeping
surfaces dry become much more important. You can't just use a block
of wood exposed to rain for an insulator and if the base is on a
concrete pier, it has to have copper strapped around it so the
concrete isn't part of the v. gradient between the antenna and ground.
Besides arcs, RF loss is a consideration, plus the ground system has
to be extended because the induced earth currents are farther out.
It's a lot of trouble and expense for a slightly lower take off.
73
Rob
K5UJ
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