For those who have the skill and interest in homemade electronics, and those who know someone who do, read the rest of this post to find out how to make a phone charger that attaches to a bike to use wind power as an energy source.
While not so complicated, it does require a few things that are not just lying around most people’s houses.
Step 1: A soldering iron, a glue gun, a wire stripper and electrical tape are needed. For materials, you need:
- a CPU fan
- a toroidal inductor
- 2N2222, 2N3904 or BC547 transistor
- 5v set-up module
- 5 germanium diodes
- a perfboard
- a phone battery
- a small switch
Step 2: The fan will create an AC current that needs to be converted to DC in order to charge the phone. To do this, first look at the fan and take off the propeller. There should be three pins inside. Solder a wire to each pin, then use a multimeter to see which of the two pins puts out the highest voltage.
Create a diode bridge and connect it to the fan. The fan should be able to give out 4 bolts and 60 mA. There are lots of tutorials online that demonstrate how to make a diode bridge for those that are confused.
Step 3: The Joule Thief circuit is used for this since it won’t overload the phone and damage the battery. Solder together the circuit and then connect it to the fan through the DC output. There are also many tutorials explaining how to build a joule thief circuit.
Step 4: Connect the battery to the 5v set-up module and the circuit.
Step 5: Glue all the components to the side of the fan so the unit is compact.
Step 6: Wrap the whole thing in electrical tape for protection.
Then it’s ready to mount on a bike and be used!
Images credit: Tamas (Instructables user Imetomi)