The measured fields by the consultant show that no "notch" exists in the
elevation pattern of that monopole from 0-3 degrees. Nor would one appear
in the elevation pattern of ANY monopole up to 5/8-wave in height.
Anyone who drives away from an AM BC station would quickly realize the field
continues for a very long distance and is not that much weaker than direct
wave until we get a fair distance out, perhaps 10-20 km for a few dB down
from direct wave.
This is pretty old stuff.
The misconception comes from EZNEC and other programs that calculate pattern
at many wavelengths away from the antenna over flat earth.
On several occasions the author of EZNEC told me he never wanted to include
TOA in his program because it would be misused. Since a competing program
had it, he reluctantly included it. I may be mistaken, but I think he
mentioned EZNEC calculated pattern at 50 or 100 wavelengths, not infinite
distance.
73 Tom
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Remember the PreStew coming on October 20th. http://www.kkn.net/stew for more
info.
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