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Stepping up voltage

  1. Feb 2, 2010 #1

    I'm building a Faraday flashlight and when I test my generator I'm getting about 200mA at 0.5V. The LED that I'm using is rated at 3V and the capacitor at 5.5V. After 60 seconds of shaking the capacitor only had about 150mA at 0.5v stored, so the LED didn't light. Does anyone have any ideas about how I could step up my voltage to about 3V? Would splitting up the single solenoid into 6 separate ones connected in series up the voltage?

  2. jcsd
  3. Feb 2, 2010 #2


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    There are ways of stepping up voltage, but most of them need a couple of volts minimum before they can operate. In this case I think that you'll just have to go for more turns and/or a stronger magnet.
  4. Feb 2, 2010 #3


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    Did you wind the coil yourself? All things being equal, the emf would be proportional to the number of turns so 'more is probably better' - like five times as many. For a small load like an LED, a bit of extra resistance due to the longer winding would probably not matter.
    You might benefit from some extra iron around the generator - but that might be difficult to arrange. And of course a stronger magnet is really the thing to go for. Really tasty ones can be v. cheap.
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