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Homework Help: Passive band pass filter

  1. Dec 15, 2003 #1
    hi there

    ive been attemping this question and i cannot find the equation to work it out anywhere !

    any help would be great !

    for a passive band pass filter

    from the following list choose the three components which would produce a cut off frequency closest to 7 khz and a band width of 320 hz

    resistor
    100 ohm
    680 ohm
    120 k ohm


    capacitor
    0.1 nf
    10 nf
    10 uf


    inductor
    200 mh
    3 mh
    50 mh

    many thanks
     
  2. jcsd
  3. Dec 15, 2003 #2

    chroot

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    Don't crosspost.

    Show us what you've done to get started.

    - Warren
     
  4. Dec 15, 2003 #3
    my problem is that i cannot find the equation this i what i was asking for
    i cannot get started if i cannot find the equation
     
  5. Dec 15, 2003 #4

    chroot

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    Where did you get this problem, then? There is no "formula" for a bandpass filter.

    - Warren
     
  6. Dec 15, 2003 #5
    apologies
    i am looking for the resonant frequency and the band witdh
     
  7. Dec 15, 2003 #6

    chroot

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    Uh, I gathered that. There still is no "formula" for a bandpass filter. What is the filter topology? I assume there is one R, one L, and one C -- what is the topology?

    - Warren
     
  8. Dec 15, 2003 #7
    exscuse my ignorance
    topology?
     
  9. Dec 15, 2003 #8

    chroot

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    How are the components connected together?

    - Warren
     
  10. Dec 15, 2003 #9
    in series
    there is one L, one R and one C
     
  11. Dec 15, 2003 #10

    chroot

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  12. Dec 15, 2003 #11
    to be honest this is all a little over my head
    many thanks for your help, but i think its best if i go back to my lecturer tomorrow and ask if he can explain it

    thanks again

    blair
     
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