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 ...

RT & Arduino experiment was successfully conducted at my own lab using the ALPS-EC11E RT and Arduino UNO-R3, ported with a sketch borrowed from the web. You may ask why I did not prepare my own sketch ...