I have been looking for something like this for awhile. I bought a bunch of 1 watt LEDs without the ‘star’ mounting plate, and I have been gluing them with thermal glue to aluminum and copper heat sinks that I have made from scrap and 6 AWG copper wire. I think these heat sinks from
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Often I have needed a variable resistor with a power rating of up to 10 or more watts and a resistance of several ohms up to 100 or so ohms. These are expensive and hard to find.* I’ll explain how to make an inexpensive one, but first I want to explain what I have used
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The author of Designing With LEDs has been especially busy with posting interesting articles lately. This article is about LED filaments from a Chinese seller. Closeup photos show the insides of the LED strings.
Designing With LEDs has a new review of a Cree LED T8 fluorescent light replacement. http://www.designingwithleds.com/the-new-cree-tw-series-led-t8-review-and-teardown/ The price has dropped significantly – from $30 US down to $22 US per tube. One important thing that I got from this review is that the old ballast decreases efficiency and wastes power, so it’s better to rewire
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I was reading that someone speculated that LED lamps may fail before the 25 thousand hour ratings claimed by many manufacturers. This can be caused by failure of the circuit that drives the LEDs, not the LEDs themselves. The most likely components to fail are the electrolytic capacitors, because they dry out or leak the
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I’ve been playing, er, experimenting with Geiger Counters recently, just to satisfy my curiosity. My mind’s curiosity area went into hyperdrive when I found out about this device. Just think! A detective could examine a hair to check for arsenic to see if the victim has been poisoned! Wow! I can think of other, less
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In the wiki for Joule Thief on Wikipedia, someone claimed that the Joule Thief is an Armstrong Oscillator. I dispute that claim and prove it’s wrong in the following discussion. An oscillator is capacitance and inductance ( j.omega )that forms a resonant circuit, and according to Barkhausen criterion, an amplifier that is a linear circuit
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I thought this YouTube video of power lines playing jump rope was really cute. It took a bit of work to make this video. And it looks like it has been around for a couple years. But to show how serious this is, I thought I should explain a few things about these high voltage
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I received another Designing With LEDs post today, reviewing the Feit LED replacement for a four foot two tube fluorescent light. She says it is $33 but only available from Costco. The fixture is meant to replace a four foot, two T8 tube fluorescent light fixture. The fixture is integrated – the tubes that hold
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I just received another Designing With LEDs post about Hollywood Lighting LED replacement lamp for fluorescent fixtures. This post reviews a 48 inch T8 replacement LED lamp. Quoting from the post: I used to think triacs were electrically noisy and a crude way to dim a light, but I now understand the advantage of not
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