I got a bunch of BC337-40 transistors; I don’t know why since I already have hundreds of BC338s and I haven’t really used a lot of them in years (see note). I have been using the BC337-25s because I felt that it was more representative of what the average transistor is going to be when
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I received a Google Alert with a link for this Youtube video of a JT powering a LED night light. I have some thoughts that I’d like to share. A LED or three in a night light may take only a quarter watt or less, if run from a battery. But when run from the
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I received the following comment from Mayank and this is the reply to his comment. Hi Watson, I have a 1V, 3A solar panel that I want to use to charge 6V SLA battery. I checked some other circuits on the web and they use big torriod cores with 2N3055 transistors. Can I use a
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On occasion I see others refer to the Joule Thief and flashlight (torch) page of talkingelectronics.com. He has many comments, some good, some not so good, and some that miss the mark. Someone recently mentioned the Circuit B, which is shown in one of the pictures. He talked about increasing the efficiency a lot by
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Have you read the Joule Thief topic in Wikipedia? I think it’s poorly written and lacking in comprehensive information,. It reminds me of the blind men and the elephant: one blind man felt the elephant’s trunk and said the elephant is like a snake; another blind man felt the elephant’s tail and said the elephant
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I’ve seen other weird things used for a Joule Thief coil, but this one is really odd. But it works. http://www.youtube.com/watch?v=Ca9VzrAXMgE
QS has added two nice little flashers to his web page. The first, a Simple JT Flasher, uses a regular 1.5V Alkaline cell. The second uses a rechargeable cell, and recharges it with a solar cell. I think I would not consider using the solar cell and rechargeable battery on a flasher. Why? Well, my
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I received a Google Alert for a Joule Thief schematic. They said that it is self resonant, but in order to be self resonant, there must be a tuned circuit with a capacitor and inductor. It’s really quite simple. There is no capacitor, there is no tuned circuit, and the circuit is not self resonant.
I looked at the photo in the Yahoo Group Joule Thief, and saw that it was working, but then I noticed that the BC337 transistor looked like it was backwards. I had to look at it again to make sure that I was seeing it correctly. Yup, it looked like it was in backwards, but
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In 2000 and 2001 the pirate manipulators the likes of Enron drove So Cal Edison and the other electric companies in California to the edge of bankruptcy and caused the electricity shortage, and along with that threats of rolling blackouts. I was concerned about being stuck in some elevator without a flashlight, and since LED
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