My Garage under attack from  LEDs.


    After I finished personalizing the side of my garage with LEDs, I still had room for another line of text.  I decided it would be nice to place the time there.  WHY?  You guessed it.  It just seemed like the thing to do at the time.

PHASE II:  Chronograph

Once again I sat down at a CAD program and set about laying out holes for the garage.   Using 7-segment style numbers on a 7*11 matrix didn't work out pretty, so I used a 7*13 grid instead, and arrived at the following:

    A couple more hours of marking and drilling left the garage with 125 more holes needing filled.  Over the next two days spare time I filled the holes with red LEDs.

   I once again strung the LEDs as many series of (5-LEDs and a resistor) groups, all wired to a common positive.  Since I knew 5 was a convenient number of LEDs to use, I made each segment of the display 5 LEDs long.

   Seven-Segment LEDs are generally labeled as follows:

   As I wired the LEDs, I attached the open end of the series to a terminal block, following the order shown above.  The result is a 24" tall group of common-anode 7-segment LEDs.  Grounding all but the "G" segments in the garage gave me the following result:


   So far, so good!  Now I needed a driver circuit to make the time come to life.

    A silly friend suggested I skip the driver circuit and leave it read "10:00".  His theory says that the clock is then guaranteed to be exactly correct twice each day.  His suggestion shall not be implemented in this project.

    Life got extremely busy, so the clock portion of the LEDs was dark for a few months.  Things settled down, and it was time to get back at it...