Interesting discussion, with many points coming from simulation. I am just
wondering how good the simulation is for vertical antennas since it seems
to depend on zillions of factors. Much more than for horizontal antennas.
With simulations, you find (just example) that having 64 radials gives
your 1.57 db more gain than 8 radials. Also few elevated radials are doing
pretty well. But the reality does not always match. Below are a few
examples.
A high inv L with 4 elevated radials should be perhaps 2-3 db below of a
loaded tower with 30 radials but it is 10 db below. An EU guy on 160 who
put 100 radials is loud with everyone else just barely copy, and the
standard here is at least 32 radials. My 4 sq on 80 should be perhaps 10 db
better than the high dipole for DX, but it is just 2 db better; asymmetry
is not an issue as F/B is excellent. On the other hand, verticals over salt
water on 160m should be 10db better by simulation, but they seem to be 20
db better. Imagine EU stations heard well 2 hrs before the sunset, and hear
them booming like locals half an hour before the sunset, an
unforgettable experience.
So is it an inadequate simulation problem or just a complexity of terrain?
For instance, is the far field response of verticals dependent on trees in
a forest?
Ignacy NO9E
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