FR>I have to re-work my 4 element 5 band (20 meters through 10 meters) quad.
FR>I'm being tempted with 30 and 40 meters. I'm thinking of putting them on
FR>the same antenna, but mechanical considerations have me a bit concerned.
FR>If you have had a 40 meter quad, if it hasn't failed how did you construct i
FR>If it has, what failed, and how?
FR>Thanks,
FR>Rob KL7NA/W7
Rob:
I built the 40 Mtr. "Maltese Quad" described by K1KLO a few years back
in one of the magazines. It is a linear loaded affair and uses a full
wavelength of wire, plus about 17%.
The spreaders are about 14-1/2 feet, measured from the center of the
boom. I employed the very strong fiberglass hollow rods offered by
Max-Gain of Marietta, Ga. Broke one spreader in an ice storm last
winter- the whole antenna was coated with about 1/4" of ice, then the
wind started and got the whole thing to flopping back and forth. It
broke right at the point where the double-walled reinforcement ended at
the butt end.
Moral of the story: I would not recommend any kind of a quad for a
location which is subject to ice storms. I have had several of the
home-made monsters and they have all suffered the same fate. However, I
am a firm believer that element for element they will outperform any
beam antenna.
By the way, the 40m 2-element is still in service, having been
repaired last spring. It is a great performer, rarely requiring more
than just a few calls to bust a pileup. But if she comes down a second
time, I will be replacing her with aluminum.
I can give you all the design and construction info if you are
interested.
Tom Hellem K0SN
Porterfield, Wisconsin
Thomas@CYBRZN.COM
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