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 ...

The Grove-Relay module is a digital normally-open switch. Through it, you can control circuit of high voltage with low voltage, say 5V on the controller. There is an indicator LED on the board, which ...