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    Why is it PNP instead of PPN for transistors

    I gioogled and found https://web.stanford.edu/class/archive/engr/engr40m.1178/slides/reactives.pdf which includes The calculus may not be for everyone, but, notice that if you swap current (i) for voltage (v), these look the same. That is, any intuition, understanding, you have of...
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    Why is it PNP instead of PPN for transistors

    In a normal, modern, oscillator the drive limits the voltage. Those sparks you get from big inductors are usually from suddent interruptions of the current, such as when it has substantial current running through it and you suddenly break the circuit. The stored energy in the inductor works to...
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    What causes more energy loss out of an LED or a SPARK gap

    What's the intention? That defines what is considered "loss": being not what was intended. You are considering using arc lighting? Spark gaps of that type are usually protection devices, designed to limit voltage to the voltage that breaks over the gap, prevent voltages dangerous to other parts...
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    Privacy lost

    Sobering. Thanks for posting. It seems more and more systems now have what amounts to a simple choice, access everything & synch everything, or not function.
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    Old magazine series 99 IC projects

    Diodes used to set voltage thresholds is not an uncommon technique. Here it would give a soft turn on, for each LED, I guess. . 256?, OK :) with 256 LEDs, maybe 32,768 diodes, about 150 volts and 256 resistors, ratings for that voltage & quiite a lot of current.
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    Why is it PNP instead of PPN for transistors

    Add propagation delay and race conditions to "settling". Transient behaviour of circuits, analog and digital, race conditions, analog perceptrons - all away from PNP transistor structure.
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    Why is it PNP instead of PPN for transistors

    Asynchronous logic and switched/clocked/synchronous logic can both have advantages, depending on what you are doing. Clocks are really good for knowing when to sample.
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    Where to start

    Any previous experience with potentially lethal voltages?
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    do passive rc filters have problems with 10GHz + frequencies?

    Impedance is a general terms used somewhat differently in different areas, but generally it means Z = R + jX - so the general term including resistance and reactive contributions.
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    Why is it PNP instead of PPN for transistors

    I suspect there's a cost to those one-cycle operations; namely realestate, whether it be silicon or chip count, or ROM space. . I think you get close by pipelining & having pre-fetch. If you pipeline appropiotely, you get an answer per cycle, but not witout some latency. . Maybe have a look at...
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    Why is it PNP instead of PPN for transistors

    Short answer: yes, it works upside down, but not as well. That's why they label them. It's the physics of semiconductors. Have a read on it. Grab a book, or pdf, one of those ones that starts from the physics: I little harder read, but well worth it. . If you find a good diagram of how they are...
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    Why is it PNP instead of PPN for transistors

    I saw someone once wrote "you should really look on the net before making such statements !" . Do the homework, man. Bipolar transistor theory. Look for the part under "PNP" :)
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    Water tank sensor

    I'm not sure that you can do this without adding other components, in a circuit. That is something to transform a resistance change into LED switching. The chip I suggested would lead to a small circuit. As with Bluejets' suggestion and mine, turning your resistance into a voltage & then some...
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    Water tank sensor

    SW? LM3914? Data sheet has several example circuits.
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    Generator output waveform check with cheap o-scope

    The data seems to say the input impedance of the scope is 1MOhm, so probably easy to use a resistive divide. If your probes don't have significant reactive component to their impedance, then the distortion should be minimal. . Incanescent bulbs tend to have strange, non-linear characteristics...
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    Diy generator

    There have been a couple of Stirling designs promoted for power to rural communities. There are likely designs online for ones that can be made relatively cheaply, either for this application or DIY or hobby. Still need that motor, if you insist on electrical output.
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    read NFC signal from a glucose sensor

    As NFC is inherently short distance, you may be lucky; it may have only simple security. Google for NFC libraries for your phone/device. Not sure how open Apple are about drivers.
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    Diy generator

    Competition? Judge how? Most innovative? Most efficient? Most powerful? Least dangerous? Smallest? Help us by defining "better"? . Strictly "generators"? Chemical? 100 potatoes? Energy harvesters? . have to say it, old washing machine motors were collected here too as they made good wind...
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    An intro

    Would second both of these. Great learning tools. Comparing kits that allow multiple circuits to be built reliably, I have never seen one that rivals the Philips ones available for a time, well, yes more than 40 years ago. But a wide variety are available with updated components and various...
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    An intro

    Welcome aboard. Wide range of accessible options nowadays. Give an idea of the style, your interests? Are you into analog, audio, digital, programming, ARM, arduino, Raspberry PI, phase control, robotics, AI on a PC? There are also quite a few sites offering projects & project ideas. maybe...
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