I built a 70cm directional biquad antenna, and it seems to be working pretty well; using my Baofeng GT-3 II, I've reached a couple of repeaters with good "ears" at >35km at low power (nominally 1 W) full quieting, and I've hit repeaters at >50km on high (5 W). The beam width seems fairly narrow, going from a clear signal to crackly fuzz (reported by another helpful ham) at maybe 30 degrees off-target, but only on transmit; when receiving, it doesn't seem to matter which way I'm pointing the thing. I can turn around in a full circle, point the thing up in the air, turn it sideways, stand in front of it, and anything else; it still seems to receive without much trouble, although moving it around sometimes finds dead spots. Is this unexpected behavior? Am I getting RF on the shield that needs to be cancelled out, or is this just some property of this antenna design?
Also, if anyone wants pics and a build report, I'll put up an album, but it ain't pretty; the whole thing is a quick-and-dirty first build, and it's a slightly fiddly implementation. It's got a driven element of 1/4" OD copper "refrigerator line" and a reflector made of a 1'x1' 28-gauge steel panel and a 70x50cm rectangle of hardware cloth. I've got a type-N connector as a connection point on the back.
Submitted February 16, 2017 at 12:36PM by semininja http://ift.tt/2lNOyej amateurradio
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