Hi! I would like to make a hand crank cell phone charger....
How would I make a hand crank cell phone charger from scratch (meaning, not just taking a hand crank flashlight and rigging it to charge a phone). I would really like to understand the electronics behind it all. I think this would be extremely useful if my phone died and I had no outlet available. I know I'd have to use a small motor, but how many volts? amps? etc. Thank you so much!