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Old July 14th 03, 04:33 PM
Richard Harrison
 
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Floyd Davidson wrote:
"This thing (TV microwave relay station) was located 50 miles from town
at 8500 foot up on a mountain top. They had a 50 foot tower (at the TV
studios I suppose)----they turned it on and it worked great."

So, if it wasn`t broke, why did they fix it?

Floyd also wrote:
"But somebody had the smart idea to see what happens if they slide the
dish down the tower to see if the signal would improve. It did!."

I wasn`t there, so I can only speculate, but I might have not been
surprised by those results.

On a 50-mile path with plenty of mid-path clearance, propagation is
similar to communications with a satellite. One difference at the
Arizona latitude is the vertical angle the dish path makes with the
Earth. The low angle the dish on the terrestrial path makes with the
Earth, makes it vulnerable to reflections from the Earth. The higher the
dish is placed, the more vulnerable it becomes. That`s a reason to go
high / low on a reflective path, and not high/high. (Low/low won`t make
the trip on most long paths due to Earth curvature).

Best regards, Richard Harrison, KB5WZI