Tag Archives: 555

Dark detector…

My son asked me, “Dad, can we make a circuit that turns a light on when it is dark?”… Went to the parts drawers, got some stuff together, drew up the circuit and he put it together on a breadboard. Notice the new breadboard, had to order some from Amazon as I ran out of them.

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Marquee Letters and a 555

I actually made this a while ago, but now I finally have some time to post about it.  This whole endeavor started with my wife picking up a set of marquee letters on clearance.  They are basically letters made out of white plastic with LEDs on them.  Construction wise, they are “OK”, the plastic is sturdy enough and the LEDs are bright.  But I was disappointed because the lights did nothing special, they just powered on.

I took a look at my parts drawer to see what I had available to make something more interesting out of these marquee letters.  There were a couple of microcontrollers, some decade counters, resistors, capacitors and quite a few 555 timers (I must have picked up a bunch on clearance somewhere, because I have a lot of them).  Initially I though of using one of the microcontrollers to animate the lights, then I came to my senses.  The 555 timer and a decade counter are the right tools for this job, no need to whip out a microcontroller.

The circuit was simple enough (you can search Google for LED chasers using 555 and pick one) .  I had no issues putting it together and it makes for a good simple light show.  Now off it goes into our son’s room to eat away batteries and amuse him. See video below.

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