Me and my high school friend made a DC to DC converter that would give us 30 or so volts at a couple amps from a 12 volt battery. We used germanium power transistors which could not go much above 10 kHz. The Delco’s and the 2N458A’s were our favorites – we managed to push
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A month or so ago a guy posted a plea on the Facebook group that he had these pallets of these 12VDC, 1.5 amp switch mode wall warts and he was desperate to get rid of them or he would have to throw them in the trash. He said he would take any reasonable offer
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I have a PIR (passive infrared) motion sensing light on my porch for more than a year, and I’ve noticed that it can sense some of the cars that go by. If the car has been running, like coming home it will usually trigger the light. But when a neighbor starts the cold car and
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From a comment I left in Big Clive’s youtube video https://youtu.be/jgaCYRc1-og In the past I’ve seen Clive having to replace “used up” capacitors in the ‘capacitive dropper’ circuits of low cost line operated devices. The problem seems to be common in other countries but here in the US I haven’t seen any problems with the
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The main reason I joined Facebook was to interact with others who shared my vocation and avocation, Electronics. It’s been a part of my life since I was very young. More than five years ago I joined several FB groups dealing with Electronics. During those years I have been banned from several groups not because
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Posted to FB Arduino group Sep 23 Mbihi Oliver Four hours is twice as long as 2 hours with the correct charger. Here is a secret many don’t know: Smartphones don’t necessarily charge at maximum, especially if they’re charged by a charger not made for their phone. Smartphones often have a sensing circuit that checks
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I posted this comment to FB Arduino group 2017-09-22. “Can I use a 7805 (regulator IC) to charge my cell phone?” The output is 5 volts, which is what the phone needs to charge. But the average smart phone will take more than 1 amp, up to 2 amps to charge quickly. The 7805 can’t
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Ever since I’ve been experimenting with Joule Thiefs I’ve done so with the intention of using the circuit for boosting a low voltage source to power a higher voltage circuit. So I think this Analog Devices ADP5090 is very useful for doing just that: powering circuits up to 200 mW from very low voltage power
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I’ve been getting PC boards that have all the chips operating at 5 volts, but the input voltage has to be between 7 and 12 volts. The board has a 5 volt regulator on the board, and often it is a surface mount chip. But I have dozens of 5 VDC, 1/2 amp AC adapters,
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Posted to FB group 2017 June 8, then a copy here. I found this Radio Shack power supply on Bama.edebris.com. Looks like someone drew it up. I found a few boo-boos, one being the LED having a 100k current limiting resistor. It’s not going to be bright. I wonder if BK1 thermal breaker is capable
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