>The short answer is "yes." In fact, just about everybody on this list has
>either built or used one. It's called an inverted L.
This answer may be too short. Build this antenna over a perfect radial field
and the short answer may be correct. But for those making do with less than a
perfect radial field, the Kinstar design could offer some improvements. Don't
let the words "Invention" or "Patent" preclude closer consideration of this
design.
The first thing I did was to model the Kinstar vs. the "cage" antenna. Eznec
calculated a higher gain for the Kinstar. Then I added series resistances of
10, then 20 ohms, simulating poor ground. The Kinstar design then calculated
at a fractional dB loss vs. the "cage" antenna's several dB loss. I concluded
that either Eznec was in error, or that the Kinstar design DID offer some
advantage.
Wider spaced vertial wires form an RF void inside their circle. Electric lines
of force repel each other to form a circle of force lines outside the
verticals. Lossy ground inside the circle is eliminated. Even a near perfect
wire radial field close to the base of a single vertical is inefficient due to
half the fields around the radial wires being in the ground. This close-in
loss, where power concentration is high, can be eliminated or reduced by using
solid metal plate in lieu of wire radials, or by a using a Kinstar-fed cage.
The model of a four-wire vertical, forming a 40 foot diameter circle at the
base, and sloping together at the top of a 60 foot tower, looks like a winner.
Gain is maximized by using two or four horizontal topload wires. Any slope, up
or down, appears to decrease gain. I modeled a fat four-wire cage, using only
a single coax feed, and the gain dropped to that of a single wire vertical, the
only advantage being more bandwidth.
I hope to build a Kinstar this summer, between DX'peditions, and will advise if
I find any advantage of an actual working antenna. In the meantime I hope some
of you will experiment with the Kinstar, especially if you are located on a
small subdivision lot, like I am.
73, om Doug / NX4D
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