On 05/06/2012 11:10 AM, Richard Fry wrote:
> Unless that propagation path is obstructed by some physical object, nothing
> prevents such low-angle waves from traveling on to the ionosphere, which
> under the right conditions will result in their reflections returning to the
> earth as skywave.
The problem is that radiation does not just have an amplitude,
it also has a phase angle.
At certain ground resistances, the ground wave and the low angle
sky wave will cancel each other out, which moves the angle of
radiation up.
None of this is anything you really have to worry about.
Top band is a lot like camping: you do not need to outrun the
bear, you only have to outrun the other campers.
If you can get vaguely reasonable gain at 10-20 degrees takeoff
angle, you have "outrun the other campers".
--
All rights reversed.
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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