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Homework Help: How to calculate a harmonic of a square wave

  1. May 6, 2013 #1

    I'm a bit of a newbie to additive synthesis.. I just want to clarify that I am doing the correct calculation before continuing.

    If I wanted to calculate the 5th harmonic of a square wave (the fundamental freq. being 200Hz and the amplitude of the fundamental being 1)

    would the calculation be

    1/5 * sin (2 * 3.14 * 1000) =


    Thanks in advance
    1. The problem statement, all variables and given/known data

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    3. The attempt at a solution
  2. jcsd
  3. May 6, 2013 #2

    rude man

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    there's a 4/pi and a "t" missing in there somewhere ...

    other than that, yes.
  4. May 7, 2013 #3

    Actually I've just realised the 5th harmonic would be 9, so it would be

    1/9 * sin (2 * 3.14 * 9F * t) =

    But do you know what the 't' is equal to?

  5. May 7, 2013 #4

    rude man

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    No, convention is that the nth harmonic is harmonically related to the first (the fundamental) by fn = n*f1.

    "t" is time. You have a square wave that is a summation of harmonics, each of which is also a function of time (a sinusoidal one).

    You still don't have a 4/π in your formulas ... you need it to get a square wave of unity amplitude.
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