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Old May 16th 09, 07:19 PM posted to rec.radio.amateur.antenna
Art Unwin Art Unwin is offline
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First recorded activity by RadioBanter: Mar 2008
Posts: 1,339
Default Low angle radiation skip

On May 16, 11:57*am, Art Unwin wrote:
In the good old days of multi sunspots it was not unusual for 10 M
skip
ducting all around the World to the point of emmission about one
second later. Ofcourse 10M provides a low TOA. Which brings up a
question, what is the lowest angle known for a particular skip
distance or where can one find reference to such? Low angle take off
have to deal with the grazing action as well as the point of change
over from reflection and ducting as well as absorbtion and the ground
hugging phenomina. But at the back of my mind I seem to remember an
instance where a dish was able to obtain low angle television( big,
big dish) which I seem to remember was not temperature related.
Anybody got any comments that they have read in the past with respect
to low angle take off, limits e.t.c.?
Regards
Art


Maybe I should limit this post to dish antennas which are more able to
be verified
Regards
Art