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In this instructable we'll build a Nike+ sensor pouch that will attach simply and securely to your shoe - without the need to buy a brand new Nike+ shoe, or any other crazy contraptions that cost up to $10!
You will need:
1) fabric (nylon, hard canvas or other durable fabric)
2) durable thread (denim, nylon, etc)
3) Nike+ sensor
4) Needle
5) Scissors
6) velcro (1 inch)
Step 1Cut out
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It's best to use a tough fabric like neoprene, or a plastic backing-type fabric such as harder nylon or even very strong canvas. The point is to make sure that it's sturdy and will withstand some abuse. You might also want to consider the running conditions - weather and humidity - in your fabric choice.
The cutout is pretty simple. Just follow these instructions and you'll have the right size for the Nike+ sensor
It appears to be a PICmicro with a transmitter chip, the sensing is done using a Peizo speaker as an impact sensor. They even have a connector board for the sensor (Ipod size).