Your statement is basically true but even if Eznec was accurate there is very
little value to it. You get what you get and can't change it. If the beam
is designed for gain or F/B that's all you can do. Knowing the angle of
radiation is academic only.
Having a ground system of at least 1/4 wave radials is necessary for
proper operation of a 1/4 wave vertical. Making them 1/2 wave has a slight
advanage. The length beyond that of any value takes a lot of wire and space
which few have. Salt water is the only way to go.
I've found that 1/2 wave verticals don't need a large radial system for
effecient matching and operation. I've got great results with just 4 33'
radials here in Seattle on 160-40M. The 160M was 60' high top loaded 1/4
wave. The 75M vertical was a top loaded 1/2 wave 60' high. I will runs
tests at my new location in SD of side by side 1/4&1/2 waves on a few radials
vs many. I have the room to do this. I discovered how effective 1/2 wave
verticals fed with an L network to just a ground rod were in 1949. I
couldn't lay any radials were I was. I was on Main Street. W7DND in
Bremerton, Wa in the 50's was on a salt water inlet pointing East and he had
vertical beams on a beach that were killers. K7GCO
In a message dated 4/11/2002 5:38:32 PM Pacific Daylight Time,
k2av@contesting.com writes:
>
> Using EZNEC or one of the programs that allows you to specify good,
> medium, poor, very poor, use "very poor". You get no help from that
> stuff, at all.
>
> Dense and extensive ground screens are required for vertically
> polarized antennas over such composition.
>
> 73 & GL,
>
> Guy K2AV.
>
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