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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Peter asked a question about why is there a need for two separate power supplies for the same project. I guess it never occurred to me to explain this simply, so everyone can understand it. I have often had to use a separate power supply for one part of a circuit, with a second supply
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There are many circuits that are used infrequently that are powered by the usual 9 volt battery. One of these happens to be a field strength meter (FSM), which is used for detecting the power output of a transmitter such as the one a radio amateur uses. Some FSMs are very simple and use no
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I needed to pick some grapefruit from the tree, and I borrowed the picker pole from a friend. I put it in my Civic and got home, took it out and picked some ruby red grapefruit. Man, were they Delicious! So Monday I got in the car, and CLICK! It wouldn’t start. Then I noticed
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I saw a few items at DX.com that look like they could be very useful. A USB power meter, with even more information in the display, compared to the somewhat lame Practical Power meter. You won’t be caught with a dying cell phone battery with this. It’s a useful addition to your flashlight collection. This
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Earlier this year I bought a cheap cell phone charger for plugging into the car’s cigarette lighter socket. It works, but it’s s-l-o-w. I can drive for a half hour with the cell phone plugged in and it says it’s charging but it only charges a few percent. As a result, I don’t use the
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