Help me Obie Wan!

Discussion in 'General Electronics Chat' started by Ashanti, Feb 6, 2009.

  1. Ashanti

    Thread Starter Member

    Nov 22, 2008
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    I am trying to devise a device to illustrate how a t1 circuit works. Is there an ic that will feed power, consecutively, to a series of 24 lamps? Starting at 1 stepping to 24. The speed of the steps should be variable from 1 or two per second to 24 times per second.
     
  2. beenthere

    Retired Moderator

    Apr 20, 2004
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    A couple of counter IC's like CD4029's can drive two CD4028's to give the effect you wish. Add a 555 timer for the variable frequency and some Darlington arrays to drive the LED's, and there you are.
     
    Last edited: Feb 6, 2009
  3. KMoffett

    AAC Fanatic!

    Dec 19, 2007
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    beenthere,
    Isn't the 4029 a binary/decimal output counter. It looks like Ashanti wants the 24 lamps to light, one at a time, in sequential order. Wouldn't three 4017 Johnson counters driven by a 555 astable work better. I assume this is the time multiplexing of 25 channels. But then, I don't know T1 from hole in a valence ring.

    Ken
     
    Last edited: Feb 6, 2009
  4. beenthere

    Retired Moderator

    Apr 20, 2004
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    Absolutely right about the chip numbers - the original of my posts is corrected.

    The OP can tell us if the LED's light individually, or stay on in sequence, in which case the 4017's will be better,
     
  5. Wendy

    Moderator

    Mar 24, 2008
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    You guys are probably going to get tired of me saying this, but I'll be covering this here in a few days.
     
  6. Ashanti

    Thread Starter Member

    Nov 22, 2008
    12
    0
    Thank you all, very much!
     
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