How to mod HTC EVO 3D for use with Palm Touchstone wireless charger
Following up on last summer's mod to wirelessly charge the HTC EVO 4G with the Palm Touchstone charging dock (tutorial here), G&E reader drinkwd40 has come up with a similar hack for the EVO 3D.
The Touchstone is less than $15 on Amazon, which makes it one of the cheapest wireless charging solutions around, and drinkwd40 says it's much better than similar products like the Powermat. Why? Because the Touchstone "has powerful magnets in its base that connects to steel discs on the receiver, while holding the phone in place if you mount it upright in your car (even over bumps)."
Interested in wirelessly charging your EVO 3D? Find out how to do it below.
What You Need
Items
- Palm Touchstone dock (~13)
- Touchstone receiver door for Palm Pre (~$5)
- MicroUSB cable or connector
- ~26g solid wire
Tools
- Soldering kit
- Dremel
- Multitool (pliers, knife, scissors)
- Tape
- Black Epoxy
- Marker
What You Do
1. Cut off the microUSB connector leaving only the +/- pins: (a) cut clean off (b) use the Dremel with cutting disc to cut through the metal shell but leave the 5 pins uncut.
2. Use pliers to remove the middle 3 pins, leaving the outer 2 (shown in "c" above).
3. Solder each of the 2 remaining pins to a separate ~26g wire. Mix your Epoxy and apply it to the soldered area. These pins will slide so be careful not to dislodge them. This is why it must be epoxy’d first; it's difficult to put the pins back if you dislodge them). It can be easy to confuse the gold pins (what you want to solder) with the silver clips on the bottom of the microUSB assembly (these carry no current), so work carefully.
Exactly how much of the microUSB you cut off is up to you. I recommend making the metal flush with the outside of the EVO 3D so that the epoxy will be about 1.5mm out of the phone (easier to grab).
4. Remove the Touchstone receiver from the Palm Pre battery door. It's just a sticker overlaying a coil/chip, 4 steel discs, and a metal sticker. You can destroy the black sticker if you want, but you will need the other parts; don't underestimate the metal sticker.
5. Put the metal sticker on the inside of the EVO 3D back door in the same orientation as it was in the Pre. It will be lower on the 3D (not in the middle like on the Pre).
6. Trim the wires to the appropriate length. Solder the +/- contacts to the wire in step 1. Note: On my EVO 4G, I was a novice solderer and melted the plastic of the door a bit. So if this is your first time, you might want to solder it before you put it in the EVO 3D.
7. Ensure alignment works with the back cover and the Touchstone base. Plug it in et voila!
8. Now just clean things up a bit by arranging the wires out of the way to minimize bulk under the cover. Tape it in place. Close the battery door and ensure a good fit. If the cover does not fit back on the phone, grab a blow dryer and heat the door so that the plastic will stretch a bit.
I taped the door tightly closed and then heated it, which worked pretty well. I also had to widen the plastic hole for the microUSB in the battery door by about 1mm (just bent with pliers).
Thanks, drinkwd40!
