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Hello Topband,
Several people asked, so here are the details of the half-loop antenna.
The 6 element inverted L array will have to wait 'til I have more time. I
am a busy farmer these days.
The half-loop was an attempt to get a decent topband signal at a location
where I had only a pair of trees under 60 feet high, and 200 feet apart. I
had no money.
The half-loop was fed against a ground rod and radial system at the base of
one vertical leg. From the feed point, it went up 45 feet, horizontally
70 feet and then down 45 feet where the wire was grounded to a ground rod
and more radials. A heavy wire ran along the ground between the two ground
rods. I started with 8 radials at each end, but shortly thereafter an
incident involving a dump truck driving down the driveway with the bed up
yield me several thousand feet of telephone wire(it is a long way from the
house to the road) and I was able to upgrade the ground system. It was fed
directly with 50 ohm coax.
This antenna worked quite well in its favored broadside direction. It
works as a somewhat narrow spaced pair of short verticals. Considering
that no part of this antenna was higher than about 50 feet, it was great.
WW2Ys endfire pair of inverted Ls beat me by a little, probably due to the
fact that his system had much more ground wire under it. The half-loop was
extremely simple and cheap.
73, Rob K2WI
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