To All from PA0SE
Further to my email of 11.14:
I'm afraid I did not make very clear that the
vertical radiation pattern of antennas, as found in the books, do not include
the surface wave. The null in the pattern under low angles over real ground is
filled by the surface wave.
It is the surface wave we use for our LF QSO's up
to a few hundred kilometres.
I can recommend studying an old, but
very readable article:
Radio Propagation
Fundamentals
by
Kenneth Bullington
The Bell System Technical
Journal, Volume XXXVI, May 1957,
Number 3
73, Dick, PA0SE
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