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Frequency multiplier

  1. Feb 6, 2010 #1
    Hi everyone, I just want to know if anyone here have a schematics to build a frequency multiplier. All I have see for the moment is multiplier with a factor of 2. I'm searching a factor 78 frequency multiplier. Also if it exist in a chip i would like to konw it to.

    Last edited: Feb 6, 2010
  2. jcsd
  3. Feb 6, 2010 #2
    The first PLL / frequency multiplier chip (I think) was the NE565 chip in the early-mid 1970's. A block diagram of a NE565-based frequency multiplier is shown in
    In your case, the frequency divider is by 13 by 3 and last by 2. I put the divide by 2 last so that the NE565 gets a 50% duty cycle square wave. To see inside the NE565, see

    Bob S
  4. Feb 6, 2010 #3
    What is the frequency you are trying to multiply?
  5. Feb 6, 2010 #4
    it's variable from 1Hz to 20 Hz to get at the output 78Hz to 1560 Hz
  6. Feb 6, 2010 #5


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    Science Advisor
    Gold Member

    There are several ways to do this depending on how accurate you need it to be.
  7. Feb 6, 2010 #6
    I don't need a high accuracy. [tex]\pm[/tex] 2 Hz at the output is good enough for me.
  8. Feb 8, 2010 #7
    he's there someone here
  9. Feb 8, 2010 #8


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    Staff: Mentor

    What about Bob's suggestions in post #2?
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