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Wood sensor using opamp lm358

  1. Sep 2, 2016 #1
    i connected pin 4 and 8 to gnd and +5 v respectively
    .when pin 2 touches wood, or hand pin 1 is high.
    i understand skin is capacitive , but wood?
  2. jcsd
  3. Sep 2, 2016 #2


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    Your circuit is badly designed so the output has no meaning. What about pin 3?

    The output (pin 1) will be high if 1In- (pin 2) is lower than 1In+ (pin 3).

    Static electricity on your skin or the wood can easily make pin 2 higher or lower than pin 3.
  4. Sep 5, 2016 #3


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    quite an odd post
    How about posting about what you are actually trying to achieve with this op-amp :smile:

  5. Sep 5, 2016 #4


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    A circuit diagram helps everyone to understand what's being discussed. You can't expect every contributor to make a personal sketch.
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