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Help needed on designing a circuit for a digital clock (A level project)

Discussion in 'Electronic Projects Design/Ideas/Reviews' started by MutantNoodles, Feb 28, 2010.

  1. mbarazeen

    mbarazeen Member

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    the idea of using high frequency and dividing, is to cut such errors. so i dont beleive the crystal can be the cause. if it differs 4sec its nearly 10% and a crystal never diviate like that.

    ok do one thing to check you get right 200Hz at the out put of the 1st 4060, give this signal to your min and hour circuit input. so any of the hour LED should light on after (60x12)/200 = 4.6 sec. so to make it countable you can count 10 times ON of a particular LED and compare the time it takes for it, it has to be 49 sec.

    to check the 2nd IC connect LEDs at the out put of the IC (with resistors to limit current) and manually feed it by push botton, then observe how it change it state, you will have to press 12,000 times to get last state and then it will reset. you can observe the LED to change in binary counting when you press..

    about the micro switch i will post you later how to wire with RC filter or soem one can post it for you
     
  2. MutantNoodles

    MutantNoodles New Member

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    the first 4060 has an output of 200 hz, but im not sure about the second
    are all the pins you said correct?
    5,4,6,13,15,1,3
     
  3. MutantNoodles

    MutantNoodles New Member

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    how would i make the rc filter?
     
  4. dave

    Dave New Member

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  5. Hero999

    Hero999 Banned

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    Have you tested it yet?

    Does it work?

    Do you have a frequency counter?

    Some DVMs have a frequency setting which can be used to monitor the frequency of the waveform.

    Ever heard of Google?

    Anyway, I can't see why you'd need an RC filter.

    Maybe adding an RC circuit to the reset pin so it always starts at zero?
     
  6. amsung2

    amsung2 New Member

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    you might wanna take a look at this. I was trying to do the exact same thing as you. but I'm using a microcontroller and 4017s.
    I could not make it lot simpler, but if you can understand circuits and programming, you'll probably get the idea.
    mind you, I haven't completed this thing yet, as I've run into problems. but It's pretty close.
     
  7. amsung2

    amsung2 New Member

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    you might wanna take a look at this. I was trying to do the exact same thing as you. but I'm using a microcontroller and 4017s.

    http://www.electro-tech-online.com/...-for-an-8051-based-project.106992/#post875763

    I could not make it lot simpler, but if you can understand circuits and programming, you'll probably get the idea.
    mind you, I haven't completed this thing yet, as I've run into problems. but It's pretty close.
     

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