Antenna rotor (PE4KH Amateur radio - Koos van den Hout)

Somebody gave me an unused antenna rotor with a lightweight metal pole because I want to get active in amateur satellites again when the weather permits. And I complained about having to hold the antenna above my head with a recent ISS pass for which this can be a neat solution.

The rotor has been outside for a number of years and this is visible as some wear. And on removal from its previous location the cables were just clipped away.

It's a Conrad 284971 rotor, which looks like it is for rotating terrestrial television antennas or lightweight satellite dishes. It uses 3 wires to control the rotation with 18V AC and the control box has an internal motor which should be synchronized with the motor of the rotor. The good thing about Conrad is that all available manuals can be downloaded from the website. The same rotor is also sold as the "AR-303" rotor via amateur radio sites.

Antenna rotor test The first test was just the rotor mounted to an old stepladder and seeing (and hearing) it run circles. It needs a 3-wire cable between controller and rotor. The cable is just common, clockwise and counterclockwise wires. No feedback of position.

Elevation test

According to more than one source in the links below a lot of satellite passes can be received with an antenna fixed at an elevation of about 20-25 degrees and just the azimuth controlled. Since I don't have an elevation actuator (yet) I put this through the test on receiving ISS SSTV images and this worked fine. The ISS is the strongest transmitter in space I deal with so this test is not ideal, but it's a first datapoint.

Mounting the Arrow antenna

Some PVC tubing is now used to mount the Arrow antenna on the rotor. The antenna is fixed at an elevation of about 25 degrees. In a first test between the houses this worked ok and saved me from tired arms while listening to an ARISS contact.

Computer controlling the rotor

A wish for the future is to control the rotor from the computer using rotctld so I can use it from gpredict.


This page is created by Koos van den Hout PE4KH, contact information at the end of my homepage.
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