Chuck Hutton Said:
I - and a lot of DX'ers who specialize in international MW DX - would disagree
with this. There are many examples of incredible antipodal receptions, with
recent examples being the 300 kw 1557 Taiwan station received with some
regularity in Brazil.
Thomas Giella KN4LF Says:
I've been a medium frequency AM broadcast band DXer since 1965. True unskewed
antipodal propagation enhancement can only occur at frequencies that can
propagate in daylight. At any given moment many of the propagation paths that
are involved in antipodal propagation enhancement at medium frequencies are
shut down by daylight D layer absorption, period!
Most of the propagation enhancement that we may mistake for antipodal focusing
is actually via the E Valley/F Layer ducting mechanism.
73 & GUD DX,
Thomas F. Giella, KN4LF
Retired Space & Atmospheric Weather Forecaster
Plant City, FL, USA
Grid Square EL87WX
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