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Variable band pass filter

  1. Apr 4, 2013 #1
    Is there an easy way of designing a band pass filter whose pass band could be varied over a certain band??

    The pass band is in MHz range.

  2. jcsd
  3. Apr 4, 2013 #2


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    If you need an audio bandwidth then look at old MF receiver tuning circuits. They always used air spaced variable capacitors with fixed coils. If you have a difficult band pass requirement, you might consider an IF based system with an oscillator and mixer. That's the standard approach for receivers.
  4. Apr 4, 2013 #3


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    Are you wanting to make this using OP-AMPs or LC tuned circuits? How many 2nd order stages do you need to cascade?

    The easiest way is to use someone else's design. :approve:
  5. Apr 6, 2013 #4

    If I could find someone else's design I would do my job, but the problem is where to find that design
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