LCD (I2C): LCD Pin Arduino Pin VCC 5V GND GND SDA A4 SCL A5. LEDs: LED Arduino Pin Red LED D3 Yellow LED D4 Green LED D5 (Place a 220Ω resistor between each LED and GND.) Piezo Buzzer (2-pin): Buzzer ...

This is an easy tutorial showing how you can control the brightness of an LED or adjust the speed of a DC fan using Arduino Board, a small BC547 transistor and a potentiometer. In my example the whole ...