Early Morning Wake-Up call

Mine colleague called me this morning - overslept and/or alarm didn't trigger. Ironically, I'd just been googling for paintball grenades and came across something called a sonic grenade.



You basically hack a 110db personal alarm, with a simple timer circuit, put it into a suitable container, and voila! Instant piss-off'er. There are websites that do sell these, look nice, but rather pricey.

I'm now seeing whether I hack together a birthday present for my colleague comprising an alarm clock with said 110db personal alarm circuit, be an interesting side project.