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A kit version of an amp based on the Musical Machine. It’s a simple and elegant circuit. It produces a wonderful sound with a bare minimum of components. At about 5W, it’ll give you enough power to thoroughly annoy your neighbours without deafening them. An awesome, glowing, retro piece of audio equipment.

The RoboDoor9000 is a thing that open doors. It uses an Arduino to read data from an RFID reader and open electronic locks.