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Old February 28th 08, 05:24 PM posted to rec.radio.amateur.antenna
AK AK is offline
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First recorded activity by RadioBanter: Jul 2006
Posts: 10
Default Wire Antenna/ Tree interaction


"Jim Lux" wrote in message
...
marc wrote:
I'm a noob, and I'm considering installing a wire antenna using the
sole tree on my lot as one end. My question is "Is it dangerous if
the antenna touches the tree branches/leaves during transmit?" I'm
less worried about performance right now and more safety.

Marc
W5AMP


Marc - I have a thickly wooded side yard where I run 80 and 40 meter dipoles
through and over a number of tree limbs. I don't believe that at HF
frequencies (VHF & UHF is different) that the limbs and leaves make any
significant difference - unless the RF power is actually shorting into the
limbs and leaves. It will do this, if the wires are not insulated.

I run a KW (when needed) to dipoles that use #14 stranded house wire. The
antenna wires are threaded through the limbs and leaves, resting on some of
the branches. The dipoles work quite well. I do not see any fluxuation in
the SWR when it rains or the wind is blowing, so I believe the nominal
600-volt wire insulation is sufficient to prevent shorting. (I try to keep
the ends of the wires off the limbs.) The insulation on the wire will not
hurt your radiated radio signal. Good luck. Andy K4YKZ (KN4YKZ in '58)