Control a Servo Using an Audio Signal

I was looking for a way to control a servo for school project and i couldn't technically "remote control" it.  I decided to go for the simplest way that i could figure out how to control the servo.  (im sure you could do it much simpler using a digital controller but i didn't have one. )

I learned that you literally tell the servo how far to turn by using what is called pulse width modulation.  I explain how i did the first run in the video using my computer.  I eventually made a recording of my pulses and played the signal from my iphone and that made the servo turn at a certain time.

If anyone is interested i can actually do a write up on the project just let me know.