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How does the circuit in a stun gun produce high DC voltage

  1. Mar 6, 2015 #1
    How does a stun gun or a fly swatter circuit produce DC voltages that are at least 2 or 3 orders of magnitude higher than the single 9 volt DC battery used to power the device. I would appreaciate if someone can give me some information regarding the sort of components/circuits that are used to raise the batery voltage to these large levels.

    P.S. i'm an eletrical engineering student and have already taken the eletronics I course.
  2. jcsd
  3. Mar 6, 2015 #2


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    hi Gabe

    welcome to PF :)

    we try and avoid talking about weapons like that here ... don't want to give bad people ideas on how to hurt other people

    The net is full of circuits ... do a google search

  4. Mar 6, 2015 #3
    it's not for weapon purposes i was just looking at my fly swatter carefully and started wondering how it worked. If a fly swatter is a weapon then i guess i must be living in another dimension. Just mentioned the stun gun because it's a prime example.
  5. Mar 6, 2015 #4


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    Welcome to the PF, Gabe.

    We get a lot of newbies here who want to build their first electronics project, and it often involves high voltages that are dangerous if not treated correctly. That's why we are a little careful about discussing such circuits and applications.

    But to answer your question, you can use either a "boost" circuit, or a "flyback" circuit to step up a source voltage. I prefer to start with a Google Images search for such circuits, since that gives me a better selection to click into to learn more. The flyback circuit is what is used in your (old style) CRT TV to make the 25kV anode voltage for the screen. I'd guess that the fly zapper and Taser use a similar circuit.
  6. Mar 6, 2015 #5
    Thank you very much.
  7. Mar 6, 2015 #6

    jim hardy

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    Disposable cameras have a flyback converter for the flash. Most photolabs will give you a grocery sack of them for free.
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