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My Lecher Wire Demo

  1. Sep 12, 2014 #1

    Happy to have any comments on this.

    Last edited by a moderator: Sep 25, 2014
  2. jcsd
  3. Sep 12, 2014 #2
    That's cool. I'd never heard of the lecher wire.
    So, how was it that you determined the characteristic impedance to be 390 ohms?

    Also, you mentioned varying the spacing had some effect. I'd be interested to learn more about that.
  4. Sep 12, 2014 #3
    Hi Elegysix:

    I determined the characteristic impedance by putting a potentiometer on the end and adjusting it until I saw no difference in the voltage as I moved the probe along the line. And it comes out pretty close to the theoretical value based on the tubing diameter and spacing.

  5. Sep 12, 2014 #4


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    nice one Eric

    Unfortunately lecher lines are rarely seen in electronics courses these days
    but us oldies are more likely to have encountered them ... that takes me back 30 odd years to when I used them last. A fantastic teaching tool for the RF classroom :smile:

  6. Sep 18, 2014 #5
    I'm thinking about manufacturing some of these in kit form. Won't be quite as fancy as mine, though. :)
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