I was responsible for a 500' self supported installation,
AM/FM/commercial tenants, and significant effort was placed on routing strike
current away from the foundation
concrete. That stick gets hit 8-10 times a year, with no
damage, and it's been up since 1979.
The polyphaser site indicates that concrete will absorb moisture, and release
it slowly. Depending on whether there is a good conductive path through the
concrete... j bolts or welded rebar cage....you might get current to ground
that way...or, if the cage system doesn't touch earth below th e foundation,
strike current would have to flow through the concrete alone...producing added
While no one can say for sure what will happen, were it my tower, I'd have 3"
strap routed from the tower legs to a dissipative ground, above and around the
foundation, and then a radial/strap/groundrod system beyond that.
This is particularly true if I had a fixed height tower attached to my home.
I'd want to provide a nice, low impedance path the other way. Personal
preference at present is for crankup poles that live down. Let the trees take
the big hits.
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
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