Small wind generators can be very handy in various situations, on camping, fishing, sailing etc. Our DIY wind generator can be used to recharge batteries, cell phones, Ipods or even to supply LED lights.
Generator is mostly made of stepper motor taken from an old 5.25" floppy drive!
Supply and charging of connected devices is regulated with small electronic circuit (few diodes, resistor, condenser and integrated circuit), everyone who has used soldering iron can construct it.

When it is windy outside, generator of our small windmill produces electric energy sufficient for one small light bulb or charging several batteries. We have attached USB connector to wind generator which
enables charging of all modern mobile devices (Ipod, MP3/MP4 media players, smartphone...) that are usually charged via PC USB port.

5.25" FLOPPY DRIVE WINDMILL - CONSTRUCTION

First, we have opened an old generation PC286 and removed 5.25 inch floppy drive unit. After dismantling the floppy drive unit, we have carefully removed stepper motor.
We have drilled two holes with stationary drill on the shaft and directly attached the turbine (propeller).
Next, we prepared electronics which has a task to rectify alternate current and to filter and stabilize the voltage at 5 volts. You can solder all electronic components directly.

Now we have to make the remaining mechanical parts for the wind generator. We need to prepare a bracket and a turbine (propeller). Bracket can be made of aluminum tube diameter 3-4mm, and generator (stepper motor) is most easily fastened directly to the bracket using clamps. You can easily create a three-bladed propeller using the meter, pen and scissors for cutting sheet metal. You will need a sheet metal panel 0.8x0.8m, 0.5mm thick.

more details on : http://solar.freeonplate.com/floppy_windmill.htm