I’ve looked for a long time to find an inexpensive way to track Amateur Radio satellites and I’ve been interested in learning about Arduino microcontroller boards. Stay Tuned!
So the above sentence was written a few years ago and I published parts of the project to YouTube and after I had a working solution several things happened. My employer of many years wanted to position itself for an acquisition so they outsourced us all. Between that and my volunteer efforts with the HOA and local Edmond Amateur Radio club I hit burnout. I also didn’t have any spare time. So I resigned from the radio club, resigned from the HOA and started searching for a new employer.
Now as we are entering 2023 and I’ve started activating parks for Parks on the Air, I’m wanting to get back into satellites. I’m thinking however i’m simply going to use a fixed angle and hand rotate a mast attached to the car and park on high elevation locations with a good view of the horizon.
I was able to use two T.V. antenna rotors for AZ-EL tracking however there were a number of problems.
- The motors do not have a lot of torque and in the Oklahoma prairie the wind can be troublesome. When the motor stops the wind sometimes caused it to rotate back which caused the Arduino to re-engage. Often the rotor was ping-ponging back and forth.
- Another problem is weather proofing. The cases are made to be upright, not on the side. If outside for a long period of time the rain or sprinklers would eventually get into them.
- Did I mention the wind? It blew over a few times and broke the elements, bent the boom, etc.. Once was on a calm day when I didn’t bother to guy it in place then of course a storm and gust front built up and blew through. Another time was while I was taking it apart and removed the guy ropes when a gust of wind came and blew it over. These Arrow antenna elements are nice and light-weight but also brittle. They don’t bend, they just break.
- The I2O databus or the RS485 bus was getting into the RF and frequently I could hear it better than the person I was trying to talk to.
- I wanted to move this into the attic but frankly it is too large and there isn’t sufficient space for rotating. Also I was worried the summer heat would dry up the grease or liquify it..
For POTA I need something very simple and the Arduino kit is not that. I would take me every bit of an hour to setup and another hour to tear down/store. I’m going to need something that is reliable, easy, and light-weight / rooftop mountable.
2017 Arduino AZ/EL rotor controller project
This is the prototype Arduino AZ/EL Rotator using the common Channel Master TV antenna rotators. All credit for this project belongs to Joe VK3YSP and Julie VK3FOWL of the Australian SARCNET, School Amateur Radio Club http://www.sarcnet.org/projects/project_rotator.html At the time we started this project I didn’t have any Arduino experience but I did have general programming and electronics experience.
I wanted to build a satellite AZ/EL rotator that used the cheap TV rotors here in North America for several years. Something I could use at Field Day sites and at home on nice days. This would allow me to more easily talk on the sideband satellites and get off the over crowded FM easy sats. The other plans I had viewed on the Internet required manually setting the magnetic North and they counted step pulses or used resistors to determine where they were from there. It seems like a error prone way given that a computer can use a compass.
SARC had built a portable satellite tracking system using two DC motors and used HAMLIB with GPredict to control the radio and AZ/EL tracking. Theirs was extremely unique however because they also implemented the LSM303D magnetic compass allowing the Arduino to know where it was pointing in both AZ and EL! Therefore, their solution could be easily set-up, plugged-in, and it start tracking! Even if you move it, it figures it out! With a lot of help from Joe and Julie and a few Arduino manuals we created a U.S. version with the Channel Master rotors.
On 6-APR-2018 we successfully tracked FOX-1B across the sky using SatPC32 and the Arduino controller. I had to use SatPC32 instead of Gpredict because I am utilizing the ICOM IC-9100 and Gpredict is really built to control a pair of radios, not a single satellite radio.
I also had to get a modified rotor controller EXE from the developer of SatPC32 as the Arduino code needed a LF (Line Feed) as the last character but SatPC32 was sending CRLF.
<MORE TO BE POSTED SOON 2-Jan-2023>
Here is a photo of the completed prototype. I also have a youtube video of it in action.
Here is a photo of the metal box housing the Arduino.
