Someone with NEC should model fence wire as cad or zinc plated wire. Roy
Lewallen, W7EL, did so when we were comparing measured vs calculated current
in a Beverage and Roy indicated it increased current taper by double in a 500
foot wire six feet off the ground.
I know there is a tendency to dismiss claims it has high loss, but it does.
In the early 70's, when I was doing most of my experiments with Beverages I
measured the current taper in the wire as a means of estimating loss and
termination accuracy. I found that with electric fence wire (number 19 ga)
the current remaining at the end of 500 feet was only 25 % of the starting
current. When the wire was replaced with copper #16, the current taper was
50%. That's a loss change of 6 dB. 12 dB of loss per 500 ft vs 6 dB (remember
current loss is log 20, not log 10).
In South Amherst Ohio I had two perfectly terminated Beverages on Europe and
one was initially fence wire. I was trying to balance the signals to co-phase
the antennas and the signal was just under 3 dB weaker on the fence wire
antenna. When I changed the fence wire antenna to copperweld the levels
matched.
I don't think anyone could hear the difference IF they had no second antenna
up in the same direction at the same time, but just the fact there is extra
current taper indicates there will be less directivity and S//N ratio. Before
I did these tests, and before I tried to make an 80 meter dipole out of steel
fence wire, I would have sworn it was OK also.
Not all people who don't like fence wire sit in armchairs and engineer. Some
of us plod around in mud and snow with meters, and have since the early 70's,
and spend hundreds of hours making measurements instead of working DX.
73 Tom
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