Introduction: Powermat to 5v Usb Conversion
A finished product.
Step 1: Acquire Materials.
This beauty was acquired for about $2.50 at a thrift shop. It was half off day, the best day to stock up on cheap cables and cool electronics to take apart and reuse.
Also required are:
•a USB extension cable
•a soldering iron
A "helping hand" device is very useful in this project. Soldering on these little pads is hard enough already. They are available at Harbor Freight for less than $10.
Step 2: Dismantling the Reciever
Take the bottom portion of the case, and pull on the more rectangular thin edge of it. this will pull up and out, exposing a ribbon cable and the circuit board. The only screws are the ones holding the ribbon cable to the inner casing. Keep the cable if you want, it has a female micro usb and a male apple 30-pin. It is not needed for this project. Next, push the board through the hole, applying force on the large disc part.
Step 3: USB Preperation
To prepare the USB extension, cut the male end off, and remove about 1/4 inch of the outer sheathing, and any inner shielding (loose silvery wire or foil), and also remove the green and white wires (or any wire that is not red or black). Strip the red and black wires, making sure you know which is which.
Step 4: Power
At first, I was worried, because I accidentally tore the ribbon, and thought I'd have to throw it all away. But some sleuthing with a multimeter showed that the two solder pads in the bottom right (with the disc at the top, the uppermost is positive, the bottom is ground.) give approximately 5.17 volts of power. This is within the USB spec, hooray! So I soldered a cut off 6 inch USB extension on, and now there's power!
Step 5: Troubleshooting
•Will not charge iPhones. They require circuitry on the data lines also.
•If V+ is shorted to the resistor directly above it (it's very easy to do.) the receiver will not connect to the base. The voltage may also show as extremely low or flickering.