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Help with a schematic

  1. May 23, 2010 #1
    Hey, I've been working on putting this schematic together (Not my design, got it off of instructibles.)

    The-schematic.jpg

    It's a distortion pedal for a guitar, at this point I have an amplified clean sound coming through, so I know the audio amp is working. My question is, since there's a short circuit following the 220uF capacitor, won't all of the current just bypass that section with the diodes? If so, would it be better to put that part in series with the capacitor and switch?

    pinout for the op amp is here
    http://www.hobby-hour.com/electronics/lm386-power-audio.php
     
  2. jcsd
  3. May 23, 2010 #2

    DaveC426913

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    I don't see any short circuit there.
     
  4. May 23, 2010 #3
    Between the 220uF capacitor and the dpdt switch. Isn't that a short? Or am I just a dumbass and forgetting something? Probably the later, heheh.
     
  5. May 23, 2010 #4

    Redbelly98

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    For there to be a short, the wire to the right of the 220 uF cap would have to connect to ground. This is not the case here, for either position of the dpdt switch.
     
  6. May 23, 2010 #5

    DaveC426913

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    Oh, a short when the switch is closed.
     
  7. May 23, 2010 #6
    I see, so for it to be a short, the diode section (where ground is) and the negative of the cap would have to be connected to the same thing.

    Yes, that's what my concern was since if it was a short, none of the signal from the guitar would be clipped.

    Thank you for the help, guys.
     
  8. May 24, 2010 #7

    vk6kro

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    You would have to include the diodes in the circuit like this:

    [PLAIN]http://dl.dropbox.com/u/4222062/clipping%20amp.PNG [Broken]

    The output would be about 4 volts p-p and have more clipping on the positive half cycles than the negative half cycles for an input of more than 200 mV p-p assuming a gain of 20 from the 386.

    You should see the LED flashing for high inputs.
     
    Last edited by a moderator: May 4, 2017
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