KN3G rotator controller
Oct 10, 2024
During the ARRL EME Contest in August and September I was struggling to keep the dish pointed at the moon using manual methods, especially for azimith positioning. I did some research and came to the conclusion that a dual axis slew drive, normally used for solar tracking, was the way to go. These slew drives have been in use for a number of years by radio amateurs across the world to move dishes much larger than 1m offset dish, so a 3 inch model should fine. I ordered one directly from the manufacturer in China and whilst I wait for it to arrive I decided to build a KN3G controller using an Arduino Mega 2560 and Nextion 5-inch display.
In order to familiarise myself with the controller software I bought a dual channel DC motor controller board and two small DC motors with pulse encoders. I also added a GPS module so that the controller can track the sun or moon without any external PC control. The complete system was remarkably easy to put together and successfully tested on the bench. The Nextion display software, developed by Adam, VK4GHZ, exposes all the functionality you need and looks great. A few configuration changes will be required to handle the slew drive but hopefully they’ll be straightforward.