Excellent points, gentlemen. Even with a current balun/choke at the
feedpoint, the coax feedline can easily couple to the antenna & radials and
skew the pattern.
I've included approximations of my two-story house (stucco, with wire mesh)
in models of my flagpole vertical, and even though it is 50 feet away,
there can be significant pattern distortion. The real world is ugly.
73, Terry N6RY
At 11:44 AM 2005-06-13, Jim Lux wrote:
Tom's got a very good point. As far as coupling to the feedline goes, it's
much like just another radial, that happens to go off at some odd angle,
and typically at some non-tuned length. You could adequately model it as
just another wire hooked to the other radials, but in the position
comparable to the feedline would have.
At 11:26 AM 6/13/2005, Tom Rauch wrote:
You also have to watch the feedline and mounting very
carefully. When you use less than 10 radials feedline
currents start to be an issue. When you use two radials it
is a big problem.
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