How can I build an amplifying circuit to wire a vibrating motor to an alarm clock or cell phone? Answered
I will be going to college soon and have found out that my roommate gets shaken by loud noises, so I had to abandon my guitar-amp amplified phone alarm for a quieter alternative. I was referred to a vibrating alarm system that fits into pillows and runs on signal from music players and/or plain ol' alarm clock inputs, but those are waaay too expensive, and I prefer building my own over buying.
Here's the situation: I have a USB-powered vibrating massager that I got for free at some tech convention. Since it's USB-powered, I know it runs on 5 volts, which is more than my phone's 3.5 mm plug can deliver. How can I build an amplifier circuit that will boost the signal from my phone enough to run the motor?