You are misinterpreting the model data by looking at the shape of the
pattern rather than the relative strength of the pattern at angles of
interest. Example -- the so-called "take off angle" simply shows the
vertical angle where the signal is the strongest. FAR more important to
look at the field strength at various angles as the height is varied.
Many people talk about and look at TOA, and it causes them to pick antennas
that are actually worse just because the TOA is at the correct angle. :)
If you look at a low dipole, it has just about the same gain as a low loop.
Being a loop helps moderate impedance on harmonics, but not much else.
I have 300 ft of height here. For the most part, a vertical did as well or
better than a dipole at any height and distance. The exceptions were at
sunrise or in magnetic storms, or within 50-200 miles (where a dipole below
150 feet works much better). Compared to a vertical, there could be 10-30
dB difference in favor of a low dipole (less than 150 ft high) within a few
hundred miles.
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