Hi Pete,
I recall reading in early text angles were measured, not modeled. The
measurements were with low height ~70 ft antennas.
As I recall the modeled results (in the later articles) were still with
fairly low fixed height droopy dipoles and yagis.
> I would agree with N4KG on one point, though -- it seems obvious that
under
> some circumstances the antenna at one or both ends of the circuit would
be
> so much too high or too low that it would discriminate against the best
> propagation mode so much that a secondary mode could actually be
stronger.
> In these golden days of 150+ solar flux, that probably will happen more
> than when the sun is less kind.
That is certainly the point everyone should agree with, with the
clarification a higher antenna may still "just happen" to put a null in the
angle of optimum propagation.
The "real" optimum angle may be quite different than the measured or
modeled optimum angle and varies from day to day and moment to moment and
can not be measured or modeled with antennas at one height. After many
suggestions wave angle can be measured near earth, I'm glad to see others
recognize the serious flaw in that thinking.
Models of wave behavior in complex and esoteric things like dirt or
ionosphere need validation or they are just guesses.
73 Tom
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