I have been following a few threads on elevated radials, and I'm getting a
little worried that I may have to switch to littering my south pasture with
the standard 120 quarter wave wires for 160 mtrs.
I saw a posting stating that 4 elevated radials (10 ft high I'll assume),
would be 5-6 db down from the 120 radials on the ground.
What are your thoughts? My modeling program won't handle wires that close
to the ground, it just treats them as perfect ground.
I experimented back in '86, and found the following: keep in mind the
antennas were far from optimum due to space restrictions at the house in
town. All antennas were in place at the same time and could be compared on
the air.
Ant 1 160 dipole, slightly bent, center at 35 feet, ends at 20 feet.
Ant 2 Butternut 40/80 verticalwith the 160 kit, on the ground, using 10
rolls of chicken wire 125 feet long, 4ft wide.
Ant 3 160 mtr inverted-L, base 12ft above ground, (30ft vertical section,
90ft horizontal), 3 quarter wave elevated radials 10 to 12 feet high.
I did alot of on the air testing, which produced very consistent results. I
sounded great on the inverted-L, weaker on the dipole, and very weak on the
Butternut.
The usual s meter readerings, using S9 as a benchmark for the L, resulted in
the dipole being a S3-4, and the Butternut a S1-2. This was consistent
throughout contacts in North America.
The Butternut had a bad heating problem apparently due to inefficiency. When
you put the spurs to it, it would change resonance, leading me to believe
the coil was sagging.
Here at the ranch I have a 135ft tower that is shunt fed, with 4 elevated
radials( the feed point is at 10ft). I have about two weeks before the
ground freezes, and I need to quit scratchin' my noggin and make up my mind
on the ground system.
I'll save the responses and do a summary.
73
Jay WC7M in Wyoming
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