Knight Rider self-made

Discussion in 'The Projects Forum' started by galih_cyber, Mar 20, 2012.

  1. galih_cyber

    Thread Starter New Member

    Mar 20, 2012
    3
    0
    i have made circuit for my knight rider light.... but, i got a problem, i used 555 ic and 4017 decoder ic. i had 2 sachems.

    1. [​IMG]

    2. [​IMG]


    actually, i want to use the 1st one but, if i use it, the current from output 0 in 4017 go back to output 5, and it has 4V voltage and also happen in other outputs, is that danger for my 4017 ic?
     
  2. Wendy

    Moderator

    Mar 24, 2008
    20,766
    2,536
    galih_cyber likes this.
  3. bertus

    Administrator

    Apr 5, 2008
    15,648
    2,347
    galih_cyber likes this.
  4. Bernard

    AAC Fanatic!

    Aug 7, 2008
    4,172
    397
    In first schem. if arrows are diodes, they are phased wrong, if not then outputs are shorting each other?
     
  5. galih_cyber

    Thread Starter New Member

    Mar 20, 2012
    3
    0
    hi bro, the arrows are the direction of the currents. and will the current which go back to the ic going to break my ic?
     
  6. Bernard

    AAC Fanatic!

    Aug 7, 2008
    4,172
    397
    One output is sinking current, another is sourcing- beeing connected- not good.
     
    galih_cyber likes this.
  7. galih_cyber

    Thread Starter New Member

    Mar 20, 2012
    3
    0
    ooh,, ok... so, i must use the 2nd circuit? because i want to see my leds shining like this: [​IMG] just use one 4017.
     
  8. Wendy

    Moderator

    Mar 24, 2008
    20,766
    2,536
    Hate to say this, but that is not a Night Rider pattern. No problems. I did discuss other patterns in my article and how to generate them.
     
  9. Markd77

    Senior Member

    Sep 7, 2009
    2,803
    594
    I thought it would be easier to find a video of the classic Kitt doing that kind of pattern. I found the new Kitt doing something similar:
    http://www.youtube.com/watch?v=UZDY2tdTlSQ
    I seem to remember the old Kitt did it when parked and was talking to the Hoff.

    On a side note, the transistors in post #1 are connected with the load at the emitter without a base resistor. Are there any disadvantages to that apart from a slight warming (at this low current level) of the transistors?
     
  10. Bernard

    AAC Fanatic!

    Aug 7, 2008
    4,172
    397
    Markd77, as shown , base resistors have little or no benefit; in the case where the base drive voltage is greater than the collector voltage, then a resistor is usefull.
     
  11. R!f@@

    AAC Fanatic!

    Apr 2, 2009
    8,754
    760
    It's the fading effect that counts.

    Actually in the kitt the lights are not LEDs when I think of it. They are filament bulbs. The red diffuser gives the color. The slow decay of the filaments gives the fading effect u know.

    So with LED's it's rather challenging job to fade it to leave the trail.
     
  12. Bernard

    AAC Fanatic!

    Aug 7, 2008
    4,172
    397
    Comet Trails are no problem; go back to Post 2 & bring up Bill's Fading LEDs, AKA Comet Trails.
     
Loading...