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Does it feel like you have to charge your phone constantly? Build a wireless charger
into your purse so you're phone is always safely stowed, slurping up electrons through
the power of induction. For this project you will need an inductive
coil set, 9V AC adapter, and a USB connector-- we have these snap-together dealies in the
Adafruit store, but you can also use an extra cable you have lying around.
The circuit has two parts - this one gets soldered to the AC adapter, and then secured
to the surface where you place your bag. I'm using this shelf at work where I always
put my purse when I come in. I protected the circuit with a little bit of heat shrink and
then taped it to the shelf along with a few magnets for precise alignment.
Solder the other coil circuit to a USB connector to connect to your phone. You can follow the
circuit diagram at the complete tutorial for this project on the Adafruit Learning System.
Test that your charger works with a multimeter before closing up the USB connector and embedding
the circuit in your bag. Every bag is different, but this one has a flat bottom with steel
feet, which will catch my alignment magnets perfectly. The two coils need to be 3mm apart
and coaxial for most efficient energy transfer. Some phones have more finicky charging requirements
than others, so if the induction coil doesn't work with yours, you can always use this circuit
to charge up a battery pack instead. Subscribe to the Adafruit channel on YouTube
for more wearable projects, and tune in for our live show every Wednesday with me, Becky
Stern.