Here's my take on radial wires- I agree that copper is a good
way to go, although some hams with some types of soils
have gotten pretty good results using aluminum fence wire.
Steel would be a very distant third choice, due both to
corrosion problems and its much higher RF resistance.
I like to use *small* gage copper wire that is insulated. Even
small diameter copper will last a good long time, even slightly
buried in the ground, so long as it is insulated. As others have
pointed out here, your transmitter RF can't tell any real
difference whether the wires are 10, 12, 14 or even 24 gage,
as in my case- just so long as you have enough radials and
they are long enough. I don't actually bury my radials- they are
all very close to the surface. They become somewhat overgrown
and buried over time.
My second reason for using a smaller gage is personal-
about 15 years ago, I had a lawnmower accident where a
small piece of 16 gage copper wire got shot into my ankle.
It went right through my blue jeans. I had it removed by a
surgeon. Luckily, it did not sever a nerve (it came close).
12/14 gage wire would make far more devastating
projectiles than 22/24 gage. BTW I have never used any 16
gage copper wire here. I assume the piece that got me was
a 'gift' from past generations- this land used to be farmed
and apparently it was part of a long forgotten trash pile.
It looked quite interesting on the x-ray, having the shape of a
question mark without the dot below. :o)
We used to pick a lot of relics out of our back yard soil that
were obviously related to the dumping of household trash.
There is a lot of 22/24 gage insulated wire in surplus. I see it
constantly at hamfests. My 80m vertical has a radial field that
was obtained by stripping the jacket off of a scrap 70ft piece
of 50 conductor 24 gage telephone cable from a construction job.
One small, neat roll of cable yielded 50 quarter wave insulated
radials. I do use the occasional odd length of 12 or 14 gage
left over from old wire antennas but I definitely favor the small
stuff. No doubt the larger gage wire lasts longer, but what I use
holds up pretty well too. 73, David K3KY
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