AFAIK, there has been little research done on this subject. I did ask Al
Christman, K3LC, about the performance of a four square where the radials were
allowed to overlap rather than being soldered together where they intersect.
His reply was that he had modeled this situation (where the radials were just
laid out and overlap) and that the array gain was very slightly higher than if
the radials were soldered together.
The problem with overlapping radials is the potential for problems when the
wire insulation deteriorates in the soil and the wires begin to contact one
another. PVC insulation will eventually fail while teflon may last a very long
time without deterioration.
The second issue is cost. You will use more wire with an overlapping system
rather than terminating the wire at the intersecting junction. Of course you
need to consider the effort of soldering the wires together.
K8MFO installed an 80 meter 4 square using about 50 teflon insulated wires
under each Hy Tower vertical. The radials overlap and are not soldered where
they overlap. SWR, dump power, and overall performance of the array is
excellent.
73, Dennis W0JX
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