Simple Experiment: Extraction of Energy from Permanent Magnets

[gyulasun]

The RattleGen: This is a permanent magnet generator I developed a couple of years ago.
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Hi Berto,

Very cool idea indeed! I like its simplicity.  Thanks for showing the video on it too.

EDIT:  just noticed Dieter's additional idea of feeding a Joule thief + LED from the puffer capacitor, that is also a good idea!

Gyula

[Bertoa]

@Dieter/gyulasun, I was feeding a Joule Thief with the output of the generator. Maybe it was the combination of parts but the LED was only flashing once in the 3 seconds. I think the JT needs more power to keep the LED burning permanent. When my electronic lab is furnished again, I go on to enhance this minimalistic circuit. I made also a bike lamp using the wheel spokes for activating the RattleGen.
https://www.youtube.com/watch?v=QwbCTU6-8jQ 

[dieter]

Maybe your Joule Thief didn't work well. Does it work with a 1.5V battery?


Additionally, you can feed the higher voltage of the back emf over some schottky diodes into the cap. Normally a joule thief oscillates at maybe 40 kHz, no way to flash only once every 3 secs.


Btw. how about using bicycle vibration for the rattle drive? When driving on gravel roads, this shoild work well, using some freely vibrating weight.

[dieter]

btw. robert murray-smith mentioned in one of his recent tube vids an smd joulethief that runs down to like 0.03 VDC, from ebay I think

[Bertoa]

Hi Dieter, thanks for your suggestions. You mention exact the investigations I want to do.
- First using the linear motion of the the bike vibrations. The rattlegen is a perfect vibration generator. It has some simularities with a ceramic transducer but it has more output power, depending on the used parts. Here is much more to gain!
- second a better joulethief will efficiently light up the LED. Maybe a suitable project for some of you? Because of the few parts, a nice circuit for a self charging flashlight!