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Electrolytic Capacitor and Potentiometer question

  1. Mar 28, 2010 #1
    Hey guys,

    I have two quick questions:

    Is the outside of an electrolytic capacitor conductive? (Should I worry about it touching some other circuit components)?

    I have a 5kOhm potentiometer that for some reason began to smoke once while testing a circuit. I powered off the circuit and tested the potentiometer (the resistance decreased from 0-1.3kOhm). After about an hour I retested the potentiometer and it was at 0-5kOhm again!! I replaced it in the SAME circuit, powered it up, and left it on for about 10 minutes. No smoke and it has worked since. Is this common?
  2. jcsd
  3. Mar 28, 2010 #2
    It should be easy enough to test with a multimeter. You mentioned measuring resistance so I assume that you have one. Just measure the resistance between two points on the outside of the cap. I'm going to guess that they're coated in non-conductive enamel.

    I'll tell ya whats common. Bugs. Lot's and lot's of bugs. Especially when you're just starting to build circuits/write software. Over time you'll develop a knack for doing it in an organized way that isn't so error prone.

    Are you using a breadboard? Pro tip: breadboards get filled up broken bits of wire and metal dust. They can become unreliable in certain spots. I can't tell you how many times I fixed a circuit by simply taking it all apart and putting in a new spot. Don't put things too close together if you can help it. The leads of the components can touch and cause problems.
  4. Mar 28, 2010 #3

    I do have a breadboard but I was not using it when this happened (the pieces were soldered).
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