• Tested updated circuit

    Chris Jones • 06/21/2022 at 15:22 • 0 comments

    Tested using the new voltage doubler circuit with my latest coil 

    I will still need to test with supercap hooked up to see charge time, but I figure this might help to charge the supercap closer to it's full voltage.

  • Updated Circuit

    Chris Jones • 06/21/2022 at 05:59 • 2 comments

    Did a little research and found out that their is a simple way to create a voltage doubler circuit by adding an additional full bridge rectifier and a couple ceramic capacitors..

    Whipped the whole thing up in the best known JS Falstad circuit simulator along with the joule thief and tested it and it seemed to do what I wanted.

    Ordered some 10uF ceramic caps to test.

  • Tested another coil

    Chris Jones • 05/14/2022 at 21:52 • 0 comments

    The order of 32 awg magnet wire came in so I wrapped a new coil, this time I also designed and added some edges to make the wrap a bit easier, this makes it more like wrapping a spool and has small holes for wire to pass through which helps to organize the wire.

    I did a 22 mm section in the middle with 10 layers which equals ~800 turns. 

    When testing with the same generic magnet setup as before (10x 1.5mm thick x 12mm magnets) I was now able to generate ~1.5v..

    Testing with 2x 10mm thick x 12m N52 rated magnets that I ordered https://jc-magnetics.com/Magnet-Cylinders/Magnet-N52-12mm-12mm-Discs, I was able to get this up to 2.5v, not exactly as much as I really wanted, but should be enough to get it working..

  • Further Prototyping and testing

    Chris Jones • 05/14/2022 at 21:25 • 0 comments

    Started prototyping the joule thief circuit to see if I needed to tweak the components a little.

    I wound the toroid with x2 24" 28 awg lengths of magnet wire which ended up with ~23 Turns.

    I then set up a basic run of the mill joule thief circuit.

    Through testing I found that a 20k potentiometer worked better for providing a good dimmer control vs 5k. I placed the pot between one of the outputs of the toroid and the transistor base.

    Manually charging the supercap with a battery to 3v allowed me to test the run time and voltage.


    I was able to run a full 1m length of 5v cob led string for ~2-3 min from 3v all the way down to ~ .4v.

  • Tested generator coil

    Chris Jones • 05/08/2022 at 07:31 • 2 comments

    Built a coil to test the power generation using some 28 awg magnet wire.

     After marking out ~25mm section in the middle of  the 1/2" tubing I did 6 layers of 28 awg, gluing it every so often to ensure it didn't uncoil on me.

    This came out to ~250-300 turns.

    When testing with the magnets I was only able to generate ~.5 volts. I tried with both 5 magnets and 10 and it still roughly the same voltage output. I think I need to get more turns to get to a higher voltage. 

    The issue is with the 28 awg wire I am only able to go 1 or 2 more layers before I use up all of the space available for the outside 1" tubing. So I need to try switching out to a smaller gauge. 

    I went ahead and put in an order for some 32 awg which should give me close to 2x the turns in the same cross section. 

    I will also redesign the drill holder and a couple coil edges to help make the process a little easier next time. A tighter and neater coil should generate a higher voltage.

  • Updated and Refined the design.

    Chris Jones • 05/03/2022 at 07:19 • 0 comments

    Updated and Refined the design to better fit the components.
    - Added a threaded top cap to allow for access to electronic components
    - Added a 2 piece base to allow a 9mm switched potentiometer to be used to turn the light on/off and dim.
    - Cleaned up the general design to make it look better.