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 ...

You will need an Arduino board, a potentiometer (I have used a 50K one), as ... Then store this value inside the speed variable that is used in the delay() to control how much time to wait until the ...

To the human eye, it looks like multiple LED’s are lit up simultaneously. [Alex] planned to use an Arduino to control this display, but it doesn’t have enough outputs on its own to control all ...