Chris Sells wrote:
I am putting up a half square antenna for twenty meters this weekend
and not exactly sure how to orient the antenna. Wondered if anyone
might be using one and have an idea of the orientation? I've read
that there good for low-angle radiation and good DX antennas. 73
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This antenna broadcasts perpendicular to the plane of the wires.
Various feed points may be used. Do a "Google" search for "W4RNL"'s
web page on antennas. He has an excellent
series on the half square there.
Personally, on the half squares I've used, I have not found the
antenna to be very good. One derivation which did work better than the
others was when the antenna is fed with a series LC circuit at the
bottom of one leg.
A better alternative in my opinion would be a full wave loop in a
triangular configuration. This antenna, if fed 17.5 % up from either
tilting leg really works well, and at 20 meters, the top height is not
all that great. If fed as described, AND
through a 1:1 balun, you get an almost perfect match to 50 ohms.
Chris, if you want, send me an email and I'll design one for you.
73
Ed
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