The conventional Joule Thief uses a single cell at 1.5V for power. It also typically uses a coil that has both windings the same number of turns. This means that the voltage across the primary, which is also the voltage across the LED, is the same as the voltage across the feedback winding. Almost all
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A question a Youtuber brought up made me think about going to the opposite extreme from the one I normally pursue: trying to get a Joule Thief to run at very low power. Normally I would try to maximize both the light output and efficiency. I started out with a run-of-the-mill Joule Thief having a
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Years ago I started seeing TIA or Thanks in advance at the end of emails and messages, and the thought occurred to me about what these people were trying to say. I’ve never used it, simply because it seemed inappropriate to me. I’ve always used thank you or thanks, meaning that I’m showing my appreciation
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One of my email correspondents and botmaker, Bill Sherman, had made some Joule Thiefs inside of a jar, but this Instructible uses diluted fluorescent ink from a Highlighter pen to diffuse the light into various colors. That’s quite a nice idea, and gives the light a very dispersed and colorful look. What I would like
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A few years ago, there were news articles about the great potential of Graphene, a type of carbon or graphite. I would say graphene to someone and they would say, “do you mean graphite?” And I would say, no graphene – no one had heard of it yet. As this article says, graphene is being
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One of my email correspondents, Paul, has built a baker’s dozen of the Joule thiefs with LED light strings, but all were white LEDs. I have a few strings of Xmas tree LED light strings, but all of them are multicolored, and are the type that run off a battery pack of four AA cells.
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I found this link to a slide show called A Complete history of Mainframe Computing by R. Arzoomanian. The pictures are fantastic. I thought this tidbit was very remarkable: “In fact, by the time it was retired in 1955, it was estimated that the ENIAC by itself did more calculations than all of humankind did up
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Here’s a picture of one of my flashlights, taken on the last day of 2006. I most likely had this posted on my late great watsonseblog. Maybe even here, too.
I drew this schematic up a few years ago (2009, IIRC) when I first made the Supercharged Joule Thief. It was supposed to help me keep track of the several SJTs that I built, and continued to build to validate the design. I suppose I should delete all of the text in the schematic, and
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There is no excerpt because this is a protected post.
