Larry,
Mentioned for completeness, at the Quartz Hill ZL6QH DX station, of
which I am a member, we decided to use high tensile 12 gauge galvanised
steel wire for replacement of any of the long Vee antennas. Legs are
typically 250 to 300 metres long. We modelled the situation and found
that losses were only fractional compared to using hard drawn copper.
Some have been installed for over a year, and Wellington has a
reputation for being "Windy Wellington". The 12 gauge high tensile
galvanised steel wire is in regular use for fences on New Zealand farms,
so is cheap and available.
The ZL6QH Vees are all fairly high (surge) impedance wires at the MF/HF
bands and that is why a few more ohms of surface resistance does not
give rise to a significant loss factor.
An LF antenna may well be a low resistance affair where series
resistance in the "top loading" is significant, at least for
transmitting efficiency. I think another reply on the reflector
mentioned using copper for an "upwire" and galvanised steel for the top
loading. In terms of "bang for buck" it could pay to concentrate on a
higher upwire than wider top loading.
73, Bob
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