-- Note: Read all directions before beginning!
First, lay all the parts out on the table, and make sure that you have everything accessible.
Cut your usb cable in half and peel back the insulation so that you have all the wires out.
Strip the ends of the wires on the usb cable. Take the green, white, and black wires and twist them together.
Heat up the soldering iron and get it ready. Remember to always use saftey glasses when soldering!
The first solder you’re going to make is from the 9v battery clip to the voltage regulator. Solder the RED (+) wire to the INPUT on the voltage regulator. Check the back of the box to make sure, but this is usually the left-most pole.
Next, solder the white, black, and green usb twisted wires, AND the ground (-) from the 9v clip to the ground on the voltage regulator. This is probably the middle pole on the voltage regulator.
Finally, solder the (+) RED wire on the USB cable to the OUTPUT of the voltage regulator. This is probably the rightmost pole.
Next, double check your solder connections to make sure they are correct and there is no solder bleed-over.
Now connect the + probe on your volt meter to pin 1 on the usb connector, and the - (black) probe to the other pins. On each pin the volt meter should read +5v. It is critical that you verify the output voltage for each pin. If you mess this up you could break your Shuffle!
If you are satisfied (and brave), connect the Shuffle to the usb connector. It should blink green, then yellow and green, and finally blink yellow steadily. If it does this, then your charger works. Congratulations! If not, check your solder joints and get your volt meter out again. And pray you didn’t fry your shuffle!
Finally, mount the parts inside the project case. I cut a notch on one end just wide enough for my usb connector, and filled the empty space with foam I had lying around from something I had shipped to myself. There’s no perfect way to do this. Just do what you think works. Heck you don’t have to mount it at all if you don’t want to!
Okay, now grab a beer and watch as your yellow light blinks on-off-on-off-on-off-on-off…