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During the T/A tests last winter I ran out 2
additional radials 150 ft. long into the sea water with 4ft long earth
rods. Recently the grass had to be cut so I brought these radial in,carefully
checking the Ant. current with and without the radials. NO DIFF!
This brought me back to the" wire in the air
theory" and I did somthing that I have been planning for some time. I added an
extra 180 ft in the zig-zag configuration,in spite of the fact that Eznec recons
that my top load is long enough to have linear current in the vert.
section,and no improvement to be gained from the additional wire in the
air.(Rad. res. only increasing from 0.069-0.070ohms). But Eznec
doesnt adequately simulate currents in the ground at these frequencies. So
I checked the Ant. current before and after. Before 3.2A after 3.7
Amps!!!
Very worth while,and once again "Wire in the Air"
is vastly superior to wire in the ground.,at my location at least. My
350mw
ERP is now 450mw ERP.
Antenna now 48ft high, vert section
42ft from top of loading coil. Horizontal top 650
ft (apart from last 180 ft which slopes to 40 ft.
Top wires in zig zag config. 73s
Laurie.
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