This discussion has drifted somewhat, from the original question,
"how to I treat the radials?". And the answer to that is, you
don't. Can't do it
without tangling in the beam. Can't effectively use the beam as
THAT said, I had a Cushcraft R7000 vertical about 5' above my LPDA
on a 60'
tower, at our old place in VT. The R7k is "ground independent", in
that it uses
a choke system to decouple the feedline, and it feeds the vertical as
if it were
electrically 3/8 wave long... something like a 200 ohm feed point.
It has several
3' long whips, where you'd expect to see radials. These are part of
It worked just fine. HOWEVER, it had a 3dB f/b ratio on any band
covered by the LPDA!
What was happening was mutual coupling between the shields of the
feedlines for each
antenna. Some serious decoupling work was needed, to eliminate the
currents from each feeder. Once those chokes were in place, the
"pattern" returned to normal.
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