> > I've seen this warning many times, but when I actually
compared a half
> > wave vertical with no radials to a quarter wave vertical
with
> > 32 radials, the difference was too close to measure (ie
less
> > than 3 dB). This comparison was done on 20 meters, so
we can't
> > be certain that the results would hold on 160 meters.
Still, it
> > does suggest that the losses aren't all that high.
"Less than 3dB" can't be considered high loss? 1 dB is huge
when signals are near noise floor.
> Maybe one of our list subscribers with EZNEC can run a
series of heights and
> shed further light on how much loss to expect.
Why would we use NEC-2 to predict a few dB change when we
know NEC-2 is off several dB for antennas close to earth (5
dB off in favor of higher efficiency in the case I saw where
a low dipole was compared in real life and in the model)?
Why would we use it when it only considers soil homogeneous
with uniform loss and virtually all soil isn't?
73 Tom
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