I took this photo just before Halloween back in 2010, after I made this Joule Thief without solder and without a toroid. It shows that you don’t have to know how to solder and you don’t have to have a toroid to make a working Joule Thief – all you need is a screwdriver. So
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I wrote this article last year about my Blue Blinkies. I have rounded many of them up and I tied them under the eaves of my house as a substitute for Xmas lights. But I ran out, and had to use a bunch of other LED blinkies. So yesterday I called up my old ExpressPCB
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The Youtuber going by the name of Sanjev21 has read my comment about using the TN0702 low gate threshold MOSFET for a Joule Thief that will start and run below 0.6V. He replied that this has a Rds(on)of 4 ohms at 2 volts, which is “too high”. The problem is that he is using a
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I got an email from amzfx<at>email.com with a link to this picture. I thought it was cool enough to blog. I figured that most Nixie tubes are driven by high voltage transistors such as the MPSA42, which are only a few cents apiece. In this case, it looks like the tube is driven by ten
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I saw this Youtube video of a schematic of a two transistor “Joule Thief” by Sanjev21 (update Nov 27 – I notice that this video has been removed – see note at end). This circuit is very similar to the one that I have already blogged. The problem that I see with the original, and
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I built the “Joule Thief” circuit in this Youtube video by Xee2 / Xee2vids. This uses a Radio Shack Cat # 273-1365 transformer, an E13007 transistor and a 51 ohm resistor. He also puts a 200uF capacitor across the resistor and a 14 millihenry choke in series with the resistor. The 120VAC primary is turned
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I received a Google Alert with a link to a Youtube video showing a blinking Joule Thief and its schematic. I examined the schematic and found that the collector of the PNP was connected to positive, and the collector of the NPN was connected to the negative. These are opposite to the polarity required for
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I was reading the comments in this Instructable and found a comment by Colin55 (Colin Mitchell of Talkingelectronics) showing a Joule Thief circuit that used a bolt and nut for a coil form. He wound 200 turns on the bolt for the primary winding and 40 turns for the feedback winding. One thing I think
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I drew this schematic years ago before Switchercad III or whatever schematic drawing package was available. It’s a three transistor design; one transistor inverts the photocell’s voltage so it shuts off during the day. The other two transistors make up the V boost circuit. The S9013 is a good transistor for this, but a better
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I built this light several years ago. I bought a LEDdynamics Micropuck 350 mA LED controller to drive a Luxeon Star 1W white LED. I used a black plastic project box, might have been from Radio Shack, as the case. I sawed the case in half, heightwise, so that it would fit in my pocket.
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