Description: This project allows for controlling the brightness of a Blue LED using a potentiometer and toggling between manual brightness and auto blink mode using a push button. A 2N2222 NPN ...

Let’s say you want to blink an LED. You might grab an Arduino and run the Blink sketch, or you might lace up a few components to a 555. But you needn’t go so fancy! [The Design Graveyard] explains how ...

The relay is driven using an NPN transistor (BC547), which allows a small control signal to safely switch a relay. This makes it possible to control electrical devices such as lamps, motors, or ...

A teacher I know is stuck, with only npn transistors in the supply cupboard and the need to create a reversible motor drive for an Arduino project. Reversing ‘bridges’ have four switches (relay ...

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 ...