So in this arduino relay control tutorial we will simply learn How to interface a Relay with Arduino. Here we are not using any Relay Driver IC like ULN2003 and will only use an NPN transistor to ...

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 ...

Connect pin 9 on the Arduino to the base pin of the TIP120. If you are looking at the transistor so that the metal tab is facing away from you, the base pin is on the left side of the transistor. This ...