Hi Greg,
First, if that antenna has insulated elements you may be heading
for problems unless you ground the elements to the boom for 160-
meter RF currents.
> continuity. As an alternative I have considered running a parallel
> conductor from the top of the tower and grounding it at the base.
Keep in mind currents flow in unexpected ways at radio
frequencies, because of the rapidly changing voltages and currents
and the way magnetic and electric fields influence currents.
A single small parallel wire will not do very much. A multiple wire
cage grounded to the tower at top and bottom with wires on every
side of the tower will do a lot towards reducing tower currents,
because the current will all try to move out into the cage. If the
cage was a perfect solid cylinder, grounded to the tower at the top
and bottom, there would be no current at all on anything inside the
cylinder!
I'd try the simple method of just running an Inverted L up alongside
the tower a few feet away from the tower, before I went through a
lot of work...but I'd keep a close eye on SWR for momentary
"jumps" to look for signs of arcing in the tower or antenna.
73, Tom W8JI
W8JI@contesting.com
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