N5IA Writes:
> I have constructed three of the TX antennas for 160 Meters
> which have been very similar to your description. I call
> them elevated Ground Planes.
All three of these systems raise the base and elevated radials
to a point at which they can be considered somewhat independent
of the earth. The behavior is expected and consistent with the
work done for the Department of Defense and reported by N7CL on
this list many years ago.
In summary, the work found significant ground losses in elevated
radial systems when the radials were 1/16 wave and below. Losses
became reasonable in the 1/8 wave range and were minimal but still
measurable as the base height reached 1/4 wave with some effects
persisting to 1/2 wave.
In addition, both the W7MCO and XZ0A antennas have enough radials
to begin to show reasonable performance even when ground mounted.
These systems are a far cry from two or four insulated radials
10 feet above ground.
73,
... Joe, W4TV
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