Ingredients:
- An old cellphone charger with a proprietary connector that won't fit into anything standard.
- A female USB connector (I took mine from a dead keyboard)
- A multimeter
- If you have a bad karma, you'll also need a 5v voltage regulator
- 15 minutes of pure fun
Phase 1: Rip open that cellphone charger connector's head and get to the two wires that will give you a 5v current (you can check that with your handy multimeter).
- If you're lucky: there will only be two wires giving exactly 5v.
- If you're not lucky: You have more than two wire and have to find the right two using your multimeter.
- If you're really not lucky: You have more than 5v and will have use that 5v current regulator.
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Phase 2: Solder the two wires to the USB connector using this diagram...
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...or this one.
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Phase 3: Using hot glue and other methods you deem appropriate, hide your bad soldering job back into the connector's head.
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Voila! 40$ saved. Now you can get McDo for your entire family and still have enough for a Starbucks tomorrow morning.