This motor and gear drive is from a mainframe computer, probably the tape drive. The gear ratio is high, probably a dozen or more motor revs for one shaft revolution. But that just makes cranking it turn the motor faster. The motor says it’s 30VDC, and it uses magnets. When I turn the makeshift crank
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I was reading a forum which showed a picture one contributor added. The schematic of a circuit consisted of one opamp of an LM324, its output feeding the base of a transistor and the – input connected to the emitter. The transistor had its emitter connected to ground through a 1 ohm resistor. The collector
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Years ago I became acquainted with one of our librarians, who was from Germany. He told me he lived in Dresden during World War 2, and he had a flashlight that had a handle which he could squeeze and it would light the bulb. But he said he lost it and everything else when the
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About March, 2004 I ordered a kit from eBay IIRC, from a guy in another country, might have been Britain. He called it a Linverter. At that time I didn’t have that much experience with DC to DC converters. I assembled it, made some modifications to it and learned more about how to get the
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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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QS sent me a link to a series of Youtube videos of xmas LED light reviews. This review is on my mind right now. It’s a review and teardown of a 15 RGB LED light string from Brite Star. This is in my opinion an excessively long video at 55 minutes. I think it would
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I put up xmas lights in the eaves. Most of them were Watson’s Blue Blinkies. I also put up some of those pigeonsnest.co.uk flashers that I built years ago. I think some of them have been flashing for a year on the same cell, so long that I figured it was a lot cheaper to
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CFL light bulbs have their disadvantages (see note below). Now that the LED light bulbs are becoming more available and cheaper, there is an alternative to the CFL problem. Yes, the LED lights are more expensive, but they save he buyer a lot in the long run. I watched this Youtube video by a
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I started out using a single pole, single throw pushbutton switch from an old mouse for the switch on my Joule Thief with timeout circuit. But I changed it to a double throw switch. It’s simple to use the single throw switch to charge or discharge the timing capacitor and start the timeout. But if
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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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