USB 5v Battery Pack

I have been thinking how to make a portable 5v battery pack with usb port.
a device to charge any usb device like mp3 players or just to power up portable hdd.

I saw a few off the internet but it doesn't have detail schematics.

I was thinking to convert this thing I had at home.
A usb charger. look in the pic for more detail.

is it anyway to conver this into a AA battery powerred device?

-will upload an image later-

Post edited by: limecity, at: 2007/05/28 09:39










Post edited by: limecity, at: 2007/05/28 09:45

Post edited by: limecity, at: 2007/05/28 09:47

Limecity, welcome to this forum I'm happy you joined us.

Can this schematic be of any help, maybe?

thanks for the reply Jeffie.

that might be a little too complicated for me.

I was thinking to make this http://gizmodo.com/gadgets/gadgets/mintyboost-diy-aa- usb-charger-177527.php

but possibly with 4 AA batts.
and I was thinking to make those out of the stuff in the photo i posted earlier.