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The Great Circle Chart of the world. The map is
centered on Seichelles Island. Other maps can be obtained
which are centered
on other cities and Locator including
your QTH locator. Basically the map provides a visual
image so you can place yourself in relation to
whatever country
you are in contact with.
Because radio waves tend to reflect specularly when they do
reflect, they would continue (if not absorbed by the earth)
around the globe back to the point
of origin and on again.
The numerous reflections compose a great circle path. Around
a circle whose center is the earth’s center.
The direction
they travel would therefore depend on the antenna
orientation.
Short Path means that the distance between the two
stations is the shortest distance along a great arc.
If the signal were to continue reflecting from earth to
ionosphere and back again, if the contact would be via long
path means that you are using the longest rather . This is
because propagation conditions on the long path are far
superior to short path propagation. Except for a north-south
path along the border between day and night, long path
openings involve both day and night time propagation.
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