Introduction: RA Drive

I am a 13-year-old hobbyist who loves everything about Arduino and space and I also love astrophotography, as you know in order to take deep sky astrophotography you must have a tracking system, my telescope mount does not have one and you can certainly buy one for $35 but, where is the fun in that. So in this project, I have designed a RA Drive for Equatorial Mounts


  • Arduino
  • DC Motor
  • EQ Mount
  • Acrylic Baseplate
  • Breadboard
  • 5V Relay
  • Transistor
  • 12V Power Supply, preferably rechargeable

Step 1: Design the Gear System

You Must first Design the Gear System, in the image above I have attached a gear to my DC Motor, which in Turn has been attached to the Telescope, using hot glue(You can also use screws and metal to attach, which is preferable).

Step 2: The Circut

In order to build the circuit, you need an Arduino A DC Motor, A Relay, and a Transistor. First, place your Transistor on the Breadboard with the flat side facing you, the center pin is going to be connected to digital pin 13 on your Arduino, Left pin of the Transistor must be connected to Ground and the Right pin of the Transistor must be connected to the Left Pin on Your Relay. The Center pin of the Relay is to be connected to the Ground supply on your external power source(3.3-12V). The Right pin of the Relay is to be connected to 5V on your Arduino. The bottom Left pin is to be connected to the Positive Terminal on Your Motor The Negative Terminal is to be connected to the positive power on your external power source, however this may vary if you live in the Northern Hemisphere you would want to let the RA Axis of your Telescope spin Counter Clockwise if you live in the Sothern Hemisphere you must let the Axis spin Clockwise. To do this just switch the leads of your motor

Step 3: The Enclosure(optinal)

To Build the Enclosure you just have to take to Arcylic Baseplates and put All your electronics inside and attach it to the side of your telescope, you can use permanent sticking mounts to do this

Step 4: Upload the Code

The last step is to Upload the code below:

The delay time varies based on your EQ Mount so Tinker Around with the Code.

const int stepPin = 13;

void setup() {



void loop() {




delay(9); }