Add more then one LED

Discussion in 'General Electronics Chat' started by jrote1, May 5, 2012.

  1. jrote1

    Thread Starter New Member

    May 5, 2012
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    circuit.JPG

    I currently have the circuit attached above. I would like to have 3 LED's replacing the 1 LED but the problem is when I add another LED the brightness decreases what can I do to get over this?

    Thanks In Advance
     
  2. nerdegutta

    Moderator

    Dec 15, 2009
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    You could try to use Ohms law, and reduce the 470Ω resistor.
     
    jrote1 likes this.
  3. Wendy

    Moderator

    Mar 24, 2008
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  4. SgtWookie

    Expert

    Jul 17, 2007
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    There's a bit more to it than Ohm's Law.
    I see a variable resistor set to 5.58k in series with a 22k resistor providing the base current for an emitter follower transistor.
    The emitter has a 470 Ohm resistor limiting maximum current through the LED.

    I'm not quite certain why you have the transistor wired as an emitter follower on the output of the 555 timer.
    Were you trying to make the brightness of the LED(s) adjustable by changing the variable resistor?
    Or is the idea to have the LED(s) fade in slowly?
     
  5. Bernard

    AAC Fanatic!

    Aug 7, 2008
    4,173
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    What color LEDs. Series or parallel? Did you check battery V with out load & with load?
     
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