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I'm exhausted, and a newb...

Discussion in 'Electronic Projects Design/Ideas/Reviews' started by Franknstein, Apr 19, 2007.

  1. Franknstein

    Franknstein New Member

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    Hey Len. thanks for the drawing, will try pick up that chip tomorrow. Few questions about the details:

    1. I take it because Gs, and E0 are outputs, I can obviously leave them disconnected, or open. I see pin 7 is an input, thus I understand why its connected high, in order to eliminate it activating. What I'm not too sure about is why did you connect pin 16 and 8 together with what looks like a 100nF capacitor?

    The rest of the circuit looks very straight forward. I also went through the truth table and checked out all the logic, seems perfect.
     
  2. ljcox

    ljcox Well-Known Member

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    The 100 nF cap is a bypass cap. (use a ceramic cap) Normally it is essential to install bypass caps - about 1 per 2 ICs. This prevents unwanted coupling via the supply line that can cause strange effects.

    In your case, you only have gating ICs, ie. no Flip Flops, counters, shift registers etc. so it may not matter. However, I recommend you install one in order to guard against the possibility of odd effects.
     
  3. Sceadwian

    Sceadwian Banned

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    Harmony is a funny thing =)
     
  4. dave

    Dave New Member

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  5. Franknstein

    Franknstein New Member

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    Huh? Explain?
     
  6. Sceadwian

    Sceadwian Banned

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    Just a reference to ljcox warning about 'odd effects' without bypass caps. If there are no bypass caps the circuits will capacitively feedback on one another. The harmonic effects that occur with that coupling are not predictable. Harmonics, especially in digital circuits are usually odd harmonics. He said 'odd effects' I thought that was kind of harmonious with harmonics =>

    One of the most wonderful musical contrivances is the barber shop quartet. If you want to hear harmonic effect first hand, get ONE of them drunk.
     
  7. Franknstein

    Franknstein New Member

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    Hi all. I have ordered those IC's for the new 7-segment LED addition, and the suppliers are taking their sweet time with it. Still very keen to make this circuit, just waiting for them. I also have a show coming up where I have to take my simulation systems, so I am really busy getting ready for it. Will let you know when I begin working on the new circuit. Thanks to all.
     
  8. grangerardo

    grangerardo New Member

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    Hello, this is my first message in the forum. I am Spanish, and my english level is not high. Excuse me if they dont understand anything. I have read the thread for a long time, and I dont know if with these schemes I can make a H shifter for the steering wheel of xbox360. if somebody speak Spanish and it can help me, I will thank you so much.

    Thanks.
     
  9. Franknstein

    Franknstein New Member

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    Hi grangerardo

    This circuit is very specific for getting a pre-made act-labs shifter working with USB.

    If you would like to build your own shifter, I would suggest checking this forum out:

    http://forum.rscnet.org/forumdisplay.php?f=186

    Hit me a pm if you have any questions.
     

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