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Old October 29th 04, 04:06 PM
bpnjensen
 
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dxAce wrote in message ...
dxAce wrote:

Diego Garcia is active again here this morning on 13254.


Transmissions have a 'watery' sound to them, as they have the past few days
indicating a possible trans-polar path.

dxAce
Michigan
USA

http://www.iserv.net/~n8kdv/dxpage.htm


Interesting - I will try to listen for them this weekend (no luck so
far...)

An observation and a question:

When a station is not antipodal to the listener (such as, say, Voice
of Nigeria or Radio New Zealand and my receiver in California), it
appears that there are only two ways a signal could reach the receiver
- either short path or long path via the Great Circle route, which
would be a straight line plotted across the Earth's surface, not
counting the Great Circle itself or the necesary skip. A signal
headed out in any other compass directions from the station in
straight lines would ultimately not arrive at the receiver, but at
some other point on Earth. (This is not the same as saying that a
station beaming its signal in some other ddirection will not reach my
receiver - we all frequently hear broadcasts intended for other
audiences, because antenna systems aren't perfect, thank goodness.)

This is why, when I listen to All India Radio or the Seychelles or
something out thataway that is *not* antipodal, it usually sounds
watery - it has no other route to my receiver except over the pole(s).

The only way a signal emanating from a station in any direction could
always reach a receiver is if the transmitter is antipodal to the
receiver - that is, directly on the opposite side of the earth. From
this, and without the immediate benefit of a globe or map, I assume
that for DxAce, Diego Garcia is nearly antipodal to his receiver; thus
his implication that signals from that site could possibly reach his
receiver via more than one path aside from a polar route.

*The Question*: Am I wrong? Is it possible, or even common, for a
transmitted signal to travel to a receiver via some route other than a
Great Circle route? Is it possible for skip to veer around corners?
People talk about and use Gray Line conditions to their advantage, but
even *that* is a straight line / Great Circle pathway when one
exmaines what is happening - are there others that weave along warped
ways?

Thanks -
Bruce Jensen