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Old November 18th 03, 02:46 AM
KØHB
 
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"Robert Casey" wrote





North/South paths were excellent, but East/West paths were

non-symmetrical,
which suggests a tilted ionosphere. The further north you were, the more
exaggerated the effect was. I was hearing the W7/VE7's weak and watery,
but they reported my signal as huge. Meanwhile W1/VE1's who I had

20-over
were CQ'ing in my face.



Didn't think that could happen. I thought light (here radio waves)
would propagate equally as well going as well as coming back.
Like "If you can see my face I also can see your face".


Imagine that the ionosphere is an imperfect mirror which reflects signals
best when they arrive at some specific angle, and reflects less well when
the signals do not arrive at that optimum angle. Now imagine that the
"mirror" is tilted to favor one direction (your signals arrive at mirror at
the right angle, but mine arrive at a more oblique angle and are
consequently refracted more than reflected, and at the same time the
reflection angle is such that my signals pass "over your head" to a more
distant point. ). I will hear you well, but my signal will be attenuated.
From my end the skip appears "short", but from your end the skip will appear
"long".

Only when the mirror is equidistant between us and when it is "flat" will
the path be symmetrical and relative signal strengths reciprocal.

73, de Hans, K0HB