In late 2009 I obtained a few dozen of these 10mm 1 watt single chip white LEDs from a Chinese vendor on eBay. My main intent was to see how long they would last in a lifetime test. I attached four of them with screws and washers to a piece of wood, and connected them
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This circuit is from a bunch of drawings that I have from the years before I started drawing circuits on the PC. It was drawn Jan 8, 2004 and built the next day. The design is much like those found on websites and in electronics magazines with the exception of D1 and R4. I’m not
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I built this in April, 2003. It uses a single AA cell and a 2 transistor V Boost circuit, see pic for the link.
I tack soldered this phase shift oscillator together and used a 2N7000 MOSFET for the PSO. The second transistor in the upper right is a 2N4401 being used as an emitter follower to drive the LED. The LED would draw too much current and load down the oscillator – the PSO has to have a
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This is a pic of the ring oscillator I built in Feb 2009. It’s the same as my earlier blog, but it has three LEDs per stage, so the supply voltage has to be higher. I’m going to try to upload the few second video. This was taken from the back because the LEDs were
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Peter is experimenting with my Supercharged Joule thief circuit. His picture is one of his recent results: a Supercharged Joule Thief flashlight. I quote: Hello and thanks for the fast answer, Now I want an SJT as a nightlight cause there are many so called “depleted” batteries lying around – I built one on breadboard
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I managed to squeeze 8 LEDs into holes on the end of the Altoids tin. The brightness is truly awesome. With that much battery current, I could have reduced the 33 ohm resistors a bit. But why push it and waste more battery current? It’s already really bright. That’s why I put the second switch
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This pic is dated Nov 2003, which was about the time I built the light. It was one of my early creations. I built the circuit which used two transistors (not a true Joule Thief), a toroid, and three white LEDs. Most impottantly it used two AA cells in series, which was kind of odd
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I built this light back in the early to mid 2000s when the LED flashlights were very expensive and generally not available. As can be seen, it runs off a single AAA cell, and lights a single LED. I used point to point wiring, then I put clear silicone seal over the circuit to hold
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Here’s a picture I posted to my watsonseblog in 2009. It shows several of the toroids I wound on Fair-Rite “suppressor sleeves” I bought from Mouser.com (They cost about 12 cents apiece). The part numbers are 2673002402 (high permeability) and 2643002402 medium-high permeability).
