> These results reveal that the field strength was not diminished
> significantly by going from 120 to 30 radials for any of the four
> antennas.
I've found systems that behave like that Bill. They almost max out
at 30 or 40 radials.
If you look at LB&E's paper...if the radials are only .234 wl long the
curve is almost totally flat at 50 radials and in the 90% eff range.
In Conyers, over poor mixed rock and clay, the curve happened
slower than here over pasture without rock.
The FCC recommends 120 1/4 wl radials and a screen because
they want to always be on the safe side and have some headroom
in case the ground system deteriorates, even though that is way
too many radials and a screen is unnecessary.
73, Tom W8JI
w8ji@contesting.com
--
FAQ on WWW: http://www.contesting.com/topband.html
Submissions: topband@contesting.com
Administrative requests: topband-REQUEST@contesting.com
Problems: owner-topband@contesting.com
|