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    Snubber circuit

    I'm working on 'improving' the Kettering system on my 1948 tractor. (Max 2000 engine RPM and 3 amps to the coil) Initially I was going to use an ignition IGBT, such as the ISL9V5045S3ST_F085, which has all of the snubber circuitry already built in. The problem is that the only practical way to...
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    NE555 reset pin using transistor

    What's the circuit to be used for?
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    Are UJT's used anymore?

    Sorry, I go the diagram wrong as I messed with it to post.
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    Are UJT's used anymore?

    O.K. My very first circuit design so be kind:) Starting at the top left C2, R3 and U1A are set to oscillate at about 30Khz. I calculated the frequency to begin with then went to trial and error to get it right. R7 limits the current to the gate of Q3. It also acts as a current limiter later.T1...
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    Book Reviews

    As a total newbie, but letting the magic smoke escape a lot less now, I needed to find books to teach myself the rudiments of electronics, and stumbled upon this site. All the books are in the public domain and freely available, no illegal torrent downloads here. I just put 'electronics' in the...
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    Wanted: Student Manual Art of Electronics

    The full version is available on the public domain for download. They have the student edition but you will have to join the waiting list to borrow it. https://archive.org/search.php?query=art%20of%20electronics
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    Are UJT's used anymore?

    I'm not sure how to post photos or circuits, but I'll try and find out. I have already completed and simulated a couple of circuits as an alternative. One using a 2N3906 the other a CD40106.
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    Are UJT's used anymore?

    I was considering using a microcontroller, but have read that the interference from generating a spark in a CDI unit does odd things to the MCU unless you design the voltage regulator properly. Uncharted territory for me as a newbie.
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    Are UJT's used anymore?

    I have a circuit diagram for a CDI trigger circuit circa the 1970's, that uses a 2N1671 UJT. Newark is the only place I can find them but at $84 each!! Looking around for an alternative that's not solid gold and jewel encrusted it seems that UJT are a thing of the past. Mouser only lists 2 and...
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    TO-220 to SMD

    Thank you, As I said the original mosfet is a Toshiba TK80E07NE and the datasheet only shows it being available in TO-220 AB package, also looking at the mosfet on the board the drain wire has been cut at a slight angle and shows bright copper. I have a bag of RFP70N06 mosfets in TO-220 so I'll...
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    TO-220 to SMD

    I bought a cheap BMS module for my headway LiFePo4 cells which was supposed to balance the cells and protect from over current charge and discharge. It didn't, but instead fried two of my headway cells and one of it's own power mosfets. Looking up the mosfet number it was a obsolete Toshiba part...
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    Off grid house lighting

    I have a similar system to your plans but have the distinct advantage of living in New Mexico with about 6.5 hours of sunlight each day. 2, 100watt Renogy panels wired in series to give about 45 volts, through a cutoff switch and into a EPever MPPT 30 amp charge controller then via a 30 amp DC...
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    MCU voltage regulator

    Remember I'm a newbie for electronics and have only just started using PIC and Atmel microcontrollers in my simple learning projects, but a question. Why don't microcontrollers have a voltage regulator built into the chip? I have some old A3141 hall sensors that can take an input voltage of up...
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    Power electronics textbook

    Take your pick https://archive.org/search.php?query=power%20electronics&and[]=mediatype%3A%22texts%22
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    Removing transformer sealant

    I have a small PCB mounted transformer from a power supply which I'm going to rewind. It has 'E' 'I' laminates which have been coated in some sort of resin. I don't think it's an epoxy as it looks like it was dipped and has a very thin layer of a slightly yellow brittle material. So far i've...
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    Diode choice

    Ouch, 50 years ago! Where did all those years go?
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    Making a Bench Top Power Supply From a 24 Volt 5 Amp Battery Charger

    I'm far from an electronics expert, very far in fact, but I'm old and have been around the block a few times, so I give the following advice honed from decades of experience in such projects. Sell it and buy a bench top power supply. It will work properly, have a warranty, end up being cheaper...
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    Getting started with PIC's

    If you have the Velleman board start by reading their manual. https://www.velleman.eu/downloads/0/user/usermanual_k8048_uk.pdf Then check Microchip's code examples. https://www.microchip.com/doclisting/TechDoc.aspx?type=CodeExamples
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    Diode choice

    But looking at the data sheet the capacitance and Vf are the same for all of them, hence the question. https://www.vishay.com/docs/88503/1n4001.pdf
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    Diode choice

    This is to total newbie question that I can't find an answer to. I'm using the 1980 National Semiconductors Voltage Regulator Handbook to design a simple regulated 5 volt output power supply for my old tractor. One of the first items in the input part of the circuit, as in most similar circuits...
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