In this quick Arduino tutorial I will explain how you can control a relay using the Arduino Board, one 1K and one 10K resistors, 1 BC547 transistor, one 6V or 12V relay, one 1N4007 diode and a 12V fan ...

Arduino Relay Basics - How It Works and How to Use It. Posted: June 3, 2025 | Last updated: June 3, 2025. Hi, I'm Bill. I'm a software developer with a passion for making and electronics.

However, whenever you are working with Mains voltage, things really must be done the correct way, so here are a few observations, to help out anyone else who may be looking at a similar project. 1.