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Modified LED Chaser Design


jar1087

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I am trying to build an LED chaser using 4017 decade counters and a 555 timer chip.  My design is based on that from this website, with a few changes:

http://www.geocities.com/lemagicien_2000/elecpage/bounlite/bounlight.html

Instead of using 9 LED's, I wanted to use 12, which required a third 4017.  I basically daisy chained it into the loop, so that now IC1 signals IC2 which signals IC3, back to IC1, etc.  The connections from IC1 to IC2 and IC2 to IC3 are through transistors, like the IC1 to IC2 connection in the schmatic. The connection from IC3 to IC1 just runs directly, like that from IC2 to IC1 in the schematic I also added an on/off switch and removed the connection between pin 5 on the 555 timer and ground, as previously I was not getting any signal out of it.  Now the circuit mostly works, but instead of only one light moving back and forth, there are three.  They seem to run in the correct sequence, but I'm not sure how to fix it so that only one LED lights at a time.

Any suggestions?

Thanks in advance.

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