This bell is driven by a software clock running on Processing on my Ubuntu Linux PC. The clapper is made with a relay driven by a transistor driven in turn by the serial port : every hour a number of pulses equal to the time is sent over the serial port driving the transistor, the relay and then the bell. Sketch and schematic at http://www.instructables.com/member/5Volt/
or http://www.5volt.eu
relly cool !
mannionator 3 years ago