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[WIP] Wireless charging TOH

Here's some more details about wireless charging TOH prototype that I did yesterday. And yes its a bit ugly hack but it works :-)

I'm working on improving it and testing different receivers and chargers to see whats the best combination.

What you need:
- Double sided glue tape or superglue
- QI receiver pad. I used following in this 1st experiement: http://www.ebay.ie/itm/290994467448 (But any 5V flat QI receiver will do).
- QI transmitter pad. In demo I used that Nokia one, but it really sucks as it is quite picky about the orientation. (I never got it working pad beeing inside the bag, but works when its outside). Most likely any generic QI charger would work.
- Some conductive wire, I just cutted legs off from generic resistors like this http://goo.gl/wvYRI3
- Soldering iron to connect 5V pins to right places. (receiver above has 5V and GND in different order that the pins on device, so I needed to hack a bit). I'll try to find receiver which orientation is better in the future.
- Small dremel & sharp knife (optional, if you want to shave half millimeter plastic off from back cover. Makes receiver fit better under the cover. Although it does fit even without shaving).

Howto:
- Shave off some plastics, and put receiver about over the place where battery is. Test that back cover closes and it looks ok.
- Either use double sided tape (I used that) or glue, and put receiver module in place.
- Put some double sided tape over the small hole where charger pins would connect.
- Solder wires to 5V and GND, and bend them in shape and press them down so they connect to double sided tape, you can also use glue to secure them in place. But good double sided glue tape is enough.

Overview pic:
http://s24.postimg.org/va2seucj9/IMG_3960.jpg

A bit of zooming:
http://s24.postimg.org/pxdy0pomt/IMG_3961.jpg

Macro pics (sloppy iron work, yes I know, its a proto):
http://s12.postimg.org/55lsqaq31/P_1...3_13_40_48.jpg
http://s12.postimg.org/nmg7h4619/P_1...3_13_33_58.jpg

Charging in action:
http://s14.postimg.org/j1tfqe0m9/charge.jpg

Update 20.12.2013:
I received another QI transmitter and receiver. This while generic QI transmitter is great, you can put device almost in any angle and it would still charge.

http://s7.postimg.org/6ybuif1ob/20131220_001.jpg

Red charging light shows up:
http://s18.postimg.org/tcf0clyex/20131220_003.jpg

Dimensions from below S4 receiver are a bit off, but lets see if I can do something with it.
http://s7.postimg.org/p2ev31zcr/20131220_002.jpg

Future improvements:
- find a better QI transmitter (that generic white one seems to be pretty nice).
- QI receiver is only for 650mA according to spec (Jolla phone seems to draw about 730mA from that so its pretty ok), and charger pins support upto 1000mA, so hunting for receiver that supports 1000mA begins.
When I measured voltage with Fluke, it seems to give 4.99V on idle (which is ok), but 4.7-4.8V when charging (which makes it charge it a little slower than it would be at 5.0V), but lets see if 1000mA versions appear on my doorsteps someday.