One-way potentiometer

Comments

• Forrest Posts: 1,341

  2007-02-12 10:50 edited 2007-02-12 10:50

  A normal potentiometer starts at zero ohms resistance and increases to it's full value in one direction. You just need to connect the wiper (center lead) and one of the outside leads. Leave the third lead disconnected.
• Bean Posts: 8,129

  2007-02-12 12:22 edited 2007-02-12 12:22

  Lightfoot,
  I don't know of ANY pot that is zero ohms when centered ?
  I think you just want a normal everyday pot.
  
  Bean.
  
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• T Chap Posts: 4,198

  2007-02-13 06:17 edited 2007-02-13 06:17

  For pots, you need to consider if you want a linear or log pot. For audio in volume control example, you would use a log pot. You would use a linear pot if you want 0 at one end, 50 in the middle and 100 at the other end.
• Mike Green Posts: 23,101

  2007-02-13 06:50 edited 2007-02-13 06:50

  Bean,
  You could combine an ordinary pot in series with a tunnel diode (remember those?). The resistances would add so you'd have positive resistance at one end, zero in the middle, and negative resistance at the other. How about that?
  Mike
  
  (Sorry I couldn't resist. originator, look up tunnel diodes and negative resistance on the Wikipedia. I'm sure you'll find some information. It's not what you might think.)
• T Chap Posts: 4,198

  2007-02-13 07:20 edited 2007-02-13 07:20

  I can imagine there are circuits to solve what he wanted to do, but I wasn't really clear as to what he was after. Interesting info though, will check it out.