Reply to "Semaphore and 555 Timer Circuit"

rtr12OGR Forum Member SUPPORTING MEMBERDIGITAL SUBSCRIBER

Wife let me off early (it's Friday!)... Problem solved - Bad CD4017 IC was the culprit. I must have killed it somehow in the earlier breadboard fiddling I guess? Strange thing though, it was working on the breadboard when I unhooked and dis-assembled it all.

I tried setting my power supply to 1 amp output, still got 1.18 volts on the 4017's VDD pin. Then with no outputs connected, no jumpers, I took ALL the ICs off the PCB and still got the 1.18 volts on the 4017's VDD. Got a new 4017, plugged it in and got 4.99 volts! Put the rest of the ICs back in place, hooked up an MTH traffic light...it worked perfectly!

Life is good!

8/30/193:10 PM

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