The current distribution from the feed point to ends doesn't taper
linearly but halfway out it isn't close to maximum. I can't model
anything here and anyway, I don't put all my trust in antenna models.
Also, the voltage present at the ends of an inverted V where the ends
are just a few feet above earth can cause loss since there is no
electrostatic shield underneath the ends as there is around the base
of a voltage fed vertical. Those verticals have mesh around their
bases (medium wave broadcast) to prevent or reduce ground dielectric
loss. The ends of a low inverted L are in a similar situation. I
also have years of operating experience during which I've noticed
stations with low hanging inverted Vs have markedly inferior signals
compared to stations with flat tops at roughly the same apex height.
But many hams think they are equivalent and I think the ARRL's
handbooks are largely responsible for that. Low inverted Vs are fine
for camp grounds and field day or if they are elevated substantially.
Others should strive to get the ends higher up away from earth.
73
Rob
K5UJ
> The above analysis would seem to be predicated on the assumption of
> uniform current in the wires. Of course, it is far from uniform, being
> heavily weighted towards the center. If the current were parabolic
> (as a rough guess), the effective height in the above example would
> be 45 feet, if you want a rule of thumb. Better yet, model it.
> Takes 5 minutes.
>
> 73
> Rick N6RK
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