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Simple LEO tracking with AZ-only rotators



>Another way to go is to look at Bob Bruninga's 
>simple antenna tracking using a inexpensive 
>Radio Shack rotor and fix the antennas pointing
>30-degrees elevation...just rotate in azimuth.

Ah, but its 10 degrees.  The satellite is only above 
30 deg less than 16% of the time and when it is, then 
it is almost 6 dB closer and you dont even need a beam.

By pointing it at 10 or 15 deg, then you get MAX
gain down on the horizon where you need it
most and where satellites spend 85% of their
time.  The gain tapers off above about 50 deg
BUT... the satellite is 8 dB closer and only that
high 8% of the time.  You still get *plenty* of 
signal there.

The point is, to not waste gain at high angles
for LEO's.   One simply does not need it there, 
but does need it on the horizon.  Now if one's
station is surrounded by trees and cannot see 
the horizon, that is the only time I would go above 
15 deg... to maybe 20 deg so that your max gain 
is trying to punch through the tree tops.

Read about it on:
http://web.usna.navy.mil/~bruninga/rotator1.html

de WB4APR, Bob
----
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