High vs Low

[Zack Widup]

>
>	Ed K4SB wrote:
>	> 
>	> 3. Do some simple trig and discover where the touchdown angle is for
>	> a take off angle of 8 degrees. That's the problem with one of my 80
>	> meter antennas. At 8000 miles or more, it's a killer...into Eu, it's
>	> worthless.
>	> 
>
>	  Well, at 8 degrees takeoff and an F2 layer height of 240 miles 
>          (which is about the highest it gets) my trig shows a one hop 
>          distance of 3415 miles.
>
>
>I suspect that you can't ignore the earth's curvature if you are talking 
>thousands of miles.   I could probably have done this in my head a few
>decades ago...
>
>Depends what Ed meant by "simple trig" I suppose...
>
>Derek AA5BT, G3NMX
>oo7 at astro.as.utexas.edu
>
>
You also have to consider that you're not dealing with reflection, but 
rather refraction in the ionosphere. Get an ionospheric ray-tracing program 
and run it on that!

						Zack W9SZ