USB bronze bell striking clock (with Arduino)

Annoy your co-workers : lead them into begging you to turn off your special PC clock !
This little rig infact interfaces via USB to your PC clock and generates hours and half hours dings on a real bronze bell. Great stuff to bring into your office and surprise then amuse then annoy your helpless friends.
From these pages I already showed something similar where a serial port was used instead of USB. Today most PCs lack of a serial port and with this design USB serves also as power source.
Arduino is at its core and interfaces to the PC clock with a simple Processing sketch, its natural counterpart by design.

Step 1: Please, a video !

Here it is.
For some reasons I couldn't merge it here directly.
The audio is awful because of the camera's poor microphone. It should give a good idea though.

Comments

[ChrysN]

That would be really cool (rather than annoying) if you used a Tibetan singing bowl and use it as a mindfulness clock.

[5Volt]

Yes, there's a bunch of better thing to strike! : see for example  http://www.5volt.eu/archives/16
Best regards Alessandro

[asp55]

Since you're using a 5v relay is there a reason you used a transistor rather than just driving it straight off the arduino digital pin?

[5Volt]

I used a transistor essentially for the power needed by the coil as micro's driving current is limited to 20mA. Even very small relays require something more than that, so a transistor is actually necessary. One transitor is not much a deal probably and might save the micro. Also, in case a larger relay is desired (for larger bells), the transistor is there to help. Best regards Alessandro

[92033]

It sounds like fun but all Greek to me with a dash of Polish thrown-in for good measure. :-) . I'd make one if I knew what you were talking about.