To: <towertalk@contesting.com>
> Date: Wed, 22 Apr 1998 21:15:19 -0500
> In your opinion, what is the best choice for the wire to be used
> as radials for a vertical antenna.
> (a). Where the radials will be buried.
> (b). Where the radials will lie on the surface of the ground.
> (c). Where the radials will be elevated (6" or more) above the
> surface of the ground.
Hi Tod,
My answer to all three is bare tinned copper buss wire. It's easy to
solder, cheap, and rugged. Size, at least according to real-world
field strength measurements from many sources, is almost
totally unimportant except for reliablility.
I pay just over 2 cents a foot for buss wire (in 5000 ft single
piece lengths on a reel), so it costs less than most troublesome
wires.
By the way, I just made ANOTHER series of measurements on radials.
These are actual field strength measurements taken at various
distances with a 1/4 wl vertical in a clear flat open pasture, and
also compared that antenna on the air with other antennas.
Four elevated radials were down ~1 dB from sixteen BARE wires
stapled to the earth, and 60 radials were about 4-5 dB better in all
directions.
The same results appeared in over the air tests, where listeners
reported the four radial vertical 5-10 dB down from other antennas.
When 60 radials were added, the difference disappeared.
Base impedance had little to do with ultimate performance, the
POOREST system was with coil loaded 1/8 wl radials (-7 dB from 60
radials) . It also had the lowest base resistance.(several ohms lower
than 60 radials!!).
73, Tom W8JI
w8ji.tom@MCIONE.com
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