Circuit Board

Circuit board demo showing flashing LEDs and a counter. There is also a knob that can control flash and count rate. Flashing lights are fun to build and watch!

How It Works:
Lower left subcircuit is an op-amp astable multivibrator that generates a pulse waveform (square wave)… more like _–_–_–_–_–_–_–_. The pulse rate is determined by the resistor and capacitor values around that subcircuit.

Each side of the waveform turns on certain LED lights. Waveform directly powers the red LEDs.

Then, there are frequency dividers that cut the frequency in half. This doubles the light-time for the yellow LEDs and hence slows the flash rate. Frequency gets cut in half once more to light the green LEDs, which should flash the slowest.

There is also a 7-segment display (counter) that increases by 1 each time the red LEDs flash one full cycle.

Initial flash rate can be controlled by turning the variable resistor (potentiometer).

Duration : 0:0:33


[youtube R9U0Fsr2kAE]

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19 Responses to Circuit Board

  1. 3mustardMoNkEyS says:

    agreed…there are …
    agreed…there are much more rewarding things to do than sit around watch celebs.

  2. kaloriblossom says:

    I can see that the …
    I can see that the LEDs are blinking in binary. The reds are the lowest column, the yellows are the middle, and the greens are the highest. You’re using a binary to 7-segment chip to run the number display off of the binary count right?

  3. DeMonello83 says:

    What’s this video? …
    What’s this video? you was trying a Ne555 timer, or similar?
    how to create the effect of yellow leds? thanks.

  4. moradi28 says:

    if i hook up a …
    if i hook up a capacitor to a battery and aled to the capacitor and awore to the battery again will the led blink?

  5. AcousticBruce says:

    great comment
    great comment

  6. dice142803 says:

    lol
    lol

  7. becomingzero says:

    Stick it in a car …
    Stick it in a car with loads of home made explosives and petrol and it’ll go boom.

    Oh no, i think i just commited a thought crime :/

  8. becomingzero says:

    Oh c’mon. Give the …
    Oh c’mon. Give the guy a break. There are people out there wasting their entire lives watching ego wanking celebrities get off for a pass time on youtube so what’s another 34 seconds wasted gonna matter to you i or anyone else ;)

  9. Pugragger says:

    i agree
    i agree

  10. alext7456 says:

    that was the most …
    that was the most boring video I’ve ever seen in my life

  11. HiAdrian says:

    5/5
    5/5

  12. dice142803 says:

    lol that would have …
    lol that would have been funny and cool if you turned the wheel and it went BOOM! but either than that thats amazing!

  13. Elettronico94 says:

    OK! Great!
    OK! Great!

  14. CassetteMaster says:

    Neat project!
    Neat project!

  15. red1152 says:

    wow what a waste of …
    wow what a waste of 34 seconds

  16. myx1997 says:

    perfect as cristmas …
    perfect as cristmas lights w/ a bigger display!

  17. camdaddy09 says:

    that was kinda …
    that was kinda stupid

  18. Titan752 says:

    Well…gee …
    Well…gee whillikerzth!

  19. HomicidalxTurtle says:

    uh ok
    uh ok