This part number (and ofcourse the LED type) is not very critical. If you want to use a bi-polar transistor, don’t forget to add a resistor (~1KΩ ) between Arduino D10 and the base terminal of the ...

If you’re looking for a more entry-level Arduino LED cube this 4x4x4 project is ... below – bottom right – shown passing through NPN transistors). The Arduino Mega 2560 R3 is positioned ...

Inside the cool laser-cut box is an Arduino Uno and a 9V battery, plus a current-limiting resistor and the all-important buzzer. We like how [newsonator] wired up the LEDs to the Arduino by ...