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Variable Frequency Generator question

  1. Dec 31, 2011 #1
    As you can probably guess by my last few posts, I'm looking into resonance right now. I thought it would be interesting to make a device that could hit a specific resonant frequency, maybe even smash an object. Sure, people have done it, but...fun :)
    Anyhow, I was looking on how to make one. Could I simply take an old set frequency generator (say, 10 KHz) and add a potentiometer in? THen just drill a hole, and you can twiddle it down and up.
    Otherwise, I'm not sure how to construct one. How could I produce the vibrations necessary—and more important, control their frequency—for a relatively low price?
  2. jcsd
  3. Jan 3, 2012 #2


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    dunno what country you are in. ?

    Variable frequency audio oscillators are relatively readily available even as kitsets for under AU/US$150 that go from a few 100's of Hz to up to 20 - 30 kHz
    If you are looking at breaking things with resonance you will discover that it is not just being able to attain the resonant freq of the object ( say a wine glass) you will also need to feed the audio signal into an audio power amplifier to get some significant level out.
    With a calibrated dB level meter you could then do some experiments to determine the audio level needed to just make the object vibrate and the level needed to make it shatter

  4. Jan 5, 2012 #3
    United States, so I could probably buy one.
    Could I use Audacity to generate the sound, and jack it to a good speaker? If I could control the frequency of the sound by editing it, and use the speaker to amplify it, could I maybe get some noticeable vibration out then?
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