Cell Phone Charger External Battery Charger

This is a tutorial on how to create your own external battery charger.

- Battery box
- 5v step up voltage regulator
- an extra cable for your cellphone

everything was bought on eBay for less than 10 $ total

1- Find the voltage you need by looking at you cell phone wall charger sticker
2- Mine was around 5 V  so I bought a 5 V step up regulator
3- Connect the battery box to the voltage regulator using this schema http://www.sparkfun.com/datasheets/Components/LM7805.pdf

red is input , black is ground, 
the output is what you want to connect to your cell phone cable.

4- connect the cable (after cutting out the USB part )
Enjoy!

Feel free to comment is this tutorial is not clear enough.