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Help for oscillator circuits

  1. Jun 4, 2014 #1
    can someone please give me some information about electronic oscillator circuits, in particular pulse tone oscillators (thats what it says it is) consisting of a resistor and two capacitors. how does the resistance/capac effect frequency? what does the time constant have to do with it? does the time constant have an effect on the freq? is there an equation to find the freq in a circuit like this? i need help....

    heres a pic of the circuit
  2. jcsd
  3. Jun 4, 2014 #2


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    Science Advisor
    Gold Member
    2017 Award

    hi there
    welcome to PF

    you cut out all the rest of the text ... there's probably some useful info in there for you
    on the description of the osc.
    show us more of the accompanying text or a www link to the article please :smile:

    The time constant set by the R/C values determines the ratio of the on/off pulse length and that determines the overall freq of the oscillator

    It looks kinda similar to a relaxation oscillator but with variations

  4. Jun 4, 2014 #3
    hi thanks for the reply, i got this out of a manual and here is the text:

    i am a complete beginner in this field and so could you explain what you mean by the on/off pulse length

  5. Jun 4, 2014 #4
    in general the main focus is to understand the effect of changing resistance and capacitance on the freq, amplitude and wavelength of a waveform... i was just wondering about the background information and how this all works and what extra aspects are here
  6. Jun 6, 2014 #5


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    Staff: Mentor

    You are investigating this by building it and running some tests? Plot some graphs so you can show how f varies with R, and how f varies with C. Sketch all waveforms and monitor them to see how some change with change of componets.

    This does sound like a homework or prac exercise.
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