Satel Az-EL, Instruction Manual

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Elevation is easy since, with the controller indicating that the system is pointing at (0, 0),
you just have to mount the antenna(s) so that they are horizontal. A carpenter’s level can
determine that easily.
Azimuth is a little more difficult but there are solutions. For example, in the northern
hemisphere of the earth, the pole star, Polaris, indicates the direction to the north. If you have
the elevation already set, you just need to point the antenna (using the P command – see
Appendix A) at an azimuth of zero and an elevation of your latitude and it should then be
pointing at Polaris. So, looking along the antenna axis, you just need to loosen the clamps and
rotate the elevation rotor (don’t loosen the clamps holding the boom in the elevation rotor – you
don’t want to disturb the elevation setting) till the antenna points at Polaris. For example, if you
live in Arizona at a latitude of 34 degrees, you would point the antenna using the command ‘P0
34’ and the antenna would move to that position. Actually, it would move to an azimuth of zero
and an elevation of 30 degrees because it moves in ten degree steps. This means that Polaris
would be 4 degrees higher in the sky than the direction the antenna is pointed but it would be
pointing at exactly the correct azimuth.
If you have mounted the whole system at the top of a tower, you might not like the idea
of climbing the tower at night in order to see Polaris and we certainly don’t recommend it. In
fact, we caution you against doing that.
An alternative is to use the sun on a clear day. All satellite prediction programs allow
you to calculate the position of the sun during the day. If you look at the predictions of the
sun’s position, you can find the time when the sun is exactly to the south of your location; i.e.,
when the sun is at an azimuth of 180 degrees. So, using the P command, point your antenna
at the southern horizon (‘P180 0’). Then the axis of your antenna should be horizontal and
pointing at the direction directly under the sun at the time determined above. At that time, you
loosen the clamps and orient the axis so that your antennas point in that direction. If the sun is
very high and you can’t easily determine the exact position directly under the sun, you can hold
a string with a weight on it in front of and over the end of the antenna. Then the sun’s shadow
of the string should lie along the axis of your antenna when the antenna is pointed at the
azimuth of the sun.
IV. Operating the System
The AzElControl.exe program
This program provides some of the simple
controls to handle the Sat EL azimuth-elevation
rotor system and to upload data into the system
controller. When the program is running, you will
see the window adjacent. You will notice that
there are three main areas of the window. The
top button on the left is used to select the data
file to be sent to the rotor controller and to
subsequently send it. The text window is at the
top right, and the six buttons on the bottom are
used to send direct commands to the rotor