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 ...

It is very easy to build an “SMS-controlled relay” with the help of a cheap GSM modem module and a small microcontroller board. Here, I’m using the SIM800L and Arduino Nano V3 to develop a nifty ...