No, larger wire only helps from a strength/breakage/corrosion point of view.
You say you have 1000' of radials, but didn't indicate how many. As long as
you have enough of them, the wire size is immaterial. I have about 3000' of
#14 THHN down. I like insulated wire for longevity and the wire size was
whatever was cheapest at the big hardware outlet (Lowe's). I have another
1000' to go in before fall. Most of my radials are 60' long, stapled into
the lawn with "lawn staples" from DX Engineering. They work really well. The
staples hold the wires in place initially and they are absorbed by the lawn
within one growing season. I used black for the color and they are nearly
invisible until you get right on top of them, and after a few grass
cuttings, I had a hard time finding them. With about 50 radials I'm seeing
efficiency of approximately 90% here in Iowa. (80 meter inverted L)
Make sure to read the published material on optimizing radial length vs.
numbers for a given frequency. It is really good stuff, and very helpful
getting the most out of your existing space and available wire. On 80m the
optimum spacing at the far end tips is about 3 feet. If you put all your
radials down such that there is no more than 3' distance between the tips,
you will have the optimum efficiency available for that particular location
(assuming a 1/4 wave vertical). Even if you property is irregular,
(resulting in some radials quite a bit shorter than others), the simplest
way is to take the perimeter of your available radial space and run the
radials in to the feed point area at the base of the antenna such that the
tips at the perimeter are no more than 3' apart (again for 80m). I think the
relationship is linear as I recall, so if your primary focus is 40m, you
would want the tips to be no more than 1.5 feet apart.
So, design your radial system for the highest band where efficiency is a big
issue (my bet, no higher than 20m and probably no higher than 40m) and the
radial system will work as well or perhaps slightly better on all bands
lower in frequency. Length is NOT a great issue...coverage is. The key is to
get the perimeter tips close enough...once you do that, length is not much
of a consideration (and there is nothing you can do about it anyway if the
limiting factor is the perimeter available due to property lines, houses,
etc.)
Have fun!
73,
...hasan, N0AN
----- Original Message -----
From: "Jim Miller" <JimMiller@STL-OnLine.Net>
To: <towertalk@contesting.com>
Sent: Tuesday, May 16, 2006 10:45 PM
Subject: [TowerTalk] Radial wire size
> OK, Guess I'll fess up. I have told many I have 1000 ft of radials down
> around my lowly Butternut BUT I haven't told many that I used 20 gauge
> (insulated, solid) wire. I used the small stuff as it was supposed to be
> temporary only; well you know how that goes. Anyway, is the 20 gauge wire
> significantly different in performance than 18 or 16 or even 10 gauge
> wire?
>
> Tnx es 73, de Jim KG0KP
>
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