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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I wrote a short blog about the Cree LED lights recently. Last week I bought two Cree 450 Lm (40W equivalent) LED lights from Home Depot for ten bucks apiece. The UPC label number is 13959 01932. I installed one of them in a task light I have over my laptop, which gets heavy usage,
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I thought about doing this since I wrote a blog on it back in the mid 2000s. Use the Grease Spot Photometer Method to compare the outputs of LEDs. This experiment is used in Physics classes to demonstrate the relationship between candles and the distance to the light source. In my case I decided that
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I’m trying to figure out how these Miracle LED people get away with advertising a two watt LED light is equal to a 60 watt light. These are supposed to screw into the sockets of a ceiling fan, and come in a set of four for fifty bucks when tax is included. Also, they say
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I bought an EcoSmart 40 watt equivalent LED light bulb from Home Depot on sale for under $12, regularly $20. It is very similar to this one (I couldn’t find it on Home Depot’s website). It was a bright white, which seems to be the only color they have on the shelves. Apparently all of
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Paul emailed and said he has built his 12th Joule Thief. Man, this guy is Helen Wheels – an even dozen in a matter of a fortnight (or week or two, I forget which). I’ve been puttering with the TE Flashers. I made most of them on small pieces of “Woodsie” wood that I got
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I found this LED website in Germany, I like it because it’s LEDs, LEDs, and more LEDs, and not an electronics parts distributor. The LEDs are broken down into various types, standard, high power, etc., etc., etc. I’m looking for a similar website of a store in the U.S. I figure it would be best
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I found this 1.5V switched capacitor flasher circuit on talkingelectronics.com. It flashes a red LED; I haven’t tried any other color but the similar Bowden circuit will brightly flash a yellow LED. This is essentially the same circuit I blogged earlier, except this TE circuit uses only two transistors. My measurements show that it is
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I needed a bright light over my workbench to see my work better, and this project was born out of necessity. The Electronics I bought a Bivar high power white LED Mouser P/N 749-L2PGN1-F, which uses a Cree XP-G mounted on a star board along with a reflector. The cost was $10.10 US. I have
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I was watching Sohei’s “wireless” light on Youtube and I decided to build a similar one. It’s not much different from the Tesla pancake coils I was experimenting with recently. This “wireless” Joule Thief is not really wireless, because it doesn’t really radiate radio frequency energy. It’s just a transformer with the secondary winding separate
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