Any explanation of verticals needs to address the demonstrated
fact that they work very well on 160 meters, and still work well
on 80 meters but gradually become ineffective as the frequency
goes up. Either the ground or the ionosphere or both are frequency
and/or polarization dependent.
Most treatises on verticals completely punt on these issues.
Rick N6RK
Al Williams wrote:
> ----- Original Message ----- > IN REALITY I THINK WE SHOULD BE TALKING ABOUT
>> GROUND RESISTANCE...
>
>
> I have difficulty in accepting the explanation of poor vertical antenna
> performance due to ground loss.It seems to be the culprit in about all
> antenna books going way back in years but is never explained. My
> understanding is that verticals do not get the benefit of ground reflection
> that horizontals get; that the radiation of the wave may be partially
> absorbed on its path away from the antenna but this occurs not within the
> area that radials woul alleviate.
>
> This leaves the radials as providing a better return path for the return
> currents. However, it is my understanding that antennas radiate because of
> the changing (accelerating) current in them which means that the antenna is
> charging and discharging, If this is the case then the charging and
> discharging has to be offset with something that is of the opposite
> polarity. That something in the case of the vertical is the ground if there
> are no radials.
>
> When radials are added, the antenna itself can better charge and discharge
> which is the real problem with the ground resistance
> being only an inhibiter?
>
> Any corrections or explanations is welcome.
>
> k7puc
>
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