I’ve been running some AA and AAA cells on a few Joule Thiefs that use silicon transistors until the cell gets down to about a half volt, then I switch the cell to a germanium Joule Thief and run it until the LED goes out and there’s typically less than a quarter volt left in
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I received a Google alert for this website, which is clearly labeled as Joule Thief. As can be seen, the circuit shows two transistors. a single winding coil and a few other parts, which are indicative of a voltage boost circuit but definitely not a conventional Joule Thief. Some people accuse us of being pedants.
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Long ago I built a light beam communication system. It was sophisticated in that it Frequency Modulated the carrier so that it was relatively immune to interference from light sources. The light emitters were small indicator grade LEDs. Even so, I was able to get it to work at a thousand feet (305M) with the
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I put a timer on one fluorescent light and started thinking about what I had talked about in one of my earlier watsonseblogs. This topic is very important, but is seldom considered, and lack of understanding and consideration causes a lot of waste and money. First I’ll have to discuss the way it used to
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The article in the Oct 2012 Consumer Reports on LED lights mentions the L Prize, so I googled it. I found out that the DoE awardrd the L Prize to Philips. The light looked just like the one I bought but on closer examination I found that the one I bought is 12.5 watts whereas
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Quantsuff gave me permission to post his schematic of the two NPN transistor voltage booster, often mislabeled a Joule Thief. This uses an NPN transistor to drive the output transistor, which is also NPN. The commonest two transistor V booster uses a PNP to drive the NPN output transistor, and for good reason, as I
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I pulled these Siemens DL 2416 from an old PBX. They are seated into an 18 pin right angle adapter that reduces the size down to the standard 0.3 inch wide pattern. I found the datasheet for these online. Each character of the four character display consists of small segments of red LEDs. There is
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I blogged Anton’s HV JT and noticed that it uses a 2SC945. I googled for 2SC945 datasheet and found a .PDF of the datasheet from NEC. It showed that the absolute maximum collector current is 100 mA, which is way too low for a Joule Thief, which needs several hundred mA. I scrolled down to
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Question Of The Month: Every duplex electrical outlet should come with a 5V USB charging port built into the outlet next to the sockets. [ ] I agree [ ] I disagree Well, I’m afraid that someone has already thought of that*. I was in the Big Box home improvement store this weekend and they’re
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