> Among the summary conclusions reached by K5IU
> .25 wl is worst possible radial length for current
imbalance in
> elevated radials.
> .125 wl radials fed thru a common radial inductor have
much less
> current imbalance vs .25 wl radials with no significant
reduction in bandwidth.
Hi Phil,
We have to read papers very carefully. Without an actual FS
test or verification, postulations prove nothing.
If it is desirable to shorten the radial to reduce loss,
where does the article present a stopping point? Logic
should tell us something is wrong.
K5IU proposes that balancing currents increases performance.
Let me give a countering argument to the "short radial"
idea.
1.) The radials that would have the highest current would
obviously be those having the lowest resistance (impedance).
Those would be the radials over the lowest loss areas of
soil.
2.) If we shorten those radials in an effort to make all
radials have equal current, we are reducing the coupling to
good soil and shifting it to poorer spoil.
3.) If we reduce radial length, we greatly increase the
concentration of electric and magnetic fields coupled to a
small cross section of earth. The fields are not spread out
over as large an area. Increasing field density in a given
loss media always increases power dissipated as heat.
How can shifting current from radials over better soil to
radials over poorer soil reduce loss?
How can increasing field density in a lossy media decrease
loss?
If ground losses below radials vary, why would balancing
current make the radials all radiate the same amount and
cancel at high angles? That would happen only if the earth
was exactly the same under each radial, and the very fact
current varies tells us the earth's reflection isn't the
same.
This is why any article should have verifying measurements.
If we propose FS gets better, it is a simple matter to
measure FS and prove it changes the way we think it should.
In modern times no one seems to do that. We just offer
theories that often make no logical sense. If a speculation
claims we need less work for greater returns, it becomes a
good theory.
73 Tom
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