At 22:02 8/30/2002 -0400, G.E. Tucker wrote:
>Robert Sherwood, WB0JGP, "Ground Screen - Alternative to Radials", Ham
>Radio, May 1977, p 22
>
>This also discusses putting a square of sheet metal around the vertical(s),
>and using strips of sheet metal for radials. I plan on trying some of these
>ideas on my existing wire vertical for 160/80/40M.
I have seen more than one reference to adding solid plates or disks under
verticals. ON4UN's Low Band book
states "a solid metal plate of reasonable size right under antenna
(vertical) can result in notable decrease
in ground resistance, and consequently in ground loss".
So - what constitutes a "reasonable size" plate/disk to have this notable
decrease in ground resistance and loss?
1 foot? 3 feet? 10 feet?
73 Phil NA4M
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Phil Duff NA4M na4m@arrl.net Georgetown, Texas
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