Comments on: Night Joule Thief – LED Night Light Kit

By: The LED Artist

The LED Artist — Mon, 10 Mar 2014 00:14:48 +0000

Yes! They are available and still very popular.

By: Dan Maker

Dan Maker — Sun, 09 Mar 2014 23:54:56 +0000

Are these still available? I have a group that would like to build them.

By: Brian Compton

Brian Compton — Sat, 15 Feb 2014 11:33:37 +0000

Will you ever offer these Open Source?

By: The LED Artist

The LED Artist — Wed, 09 Oct 2013 16:30:40 +0000

I don’t offer the kits assembled, unless otherwise noted. I can do it for you but there will be $70 charge for assembly.

Aki

By: lungStruck » Night Joule Thief

lungStruck » Night Joule Thief — Fri, 21 Jun 2013 02:38:27 +0000

[...] circuit to build that offers some room for customization. It’s available for under $11 from The LED Artist. Tags art • electronics • joule thief • kit • LED • review [...]

By: lungStruck » Colour Night Joule Thief

lungStruck » Colour Night Joule Thief — Mon, 10 Jun 2013 00:21:42 +0000

[...] a little more exciting than a plain white LED (though, if you want a plain white LED, consider the Night Joule Thief kit). There are other technical differences (different induction method, extra circuitry to [...]

By: Tim

Tim — Fri, 10 May 2013 13:36:17 +0000

Hello, I was wondering if you can replace the light sensor with a switch. If so what will happen to the sensor adjuster will it adjust light level or does it need to be removed when remove the light sensor?
Thanks
Tim

By: chandan

chandan — Fri, 05 Oct 2012 02:32:57 +0000

Thanks for making the kit available.which kit are avialble they are very use full for me to make my project

thanks

chandan

By: chandan

chandan — Fri, 05 Oct 2012 02:30:34 +0000

THANKS

FOR HELP ME

By: The LED Artist

The LED Artist — Sun, 24 Jun 2012 17:40:39 +0000

Jan,

Just to be clear, in your comment there are a few incorrect assumptions and misunderstanding of how inductors work.
While this circuit is not super efficient, it’s much better than 10% efficiency. The short bursts of current that drives LEDs is not wasted by any means – it does get used by the LEDs.
During the 90% “on cycle” the energy is being _stored_ in the inductor, small portion of that is a loss due to the resistance and transistor C-E saturation voltage.
Finally, the output voltage of boost circuit is proportional to the duty cycle – at 50% duty you can only get double the input voltage (under the ideal condition) not the over 6V being generated in this Joule Thief circuit.

Aki