The above circuit uses a 555 timer U1 in mono stable mode. If once push button is pressed, it drives pin2 of timer momentarily to ground that triggers the 555 to deliver a high output at pin 3 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 ...