traffic light project

[MattCAnderson]

Hi Electronics Forum,

I breadboarded a 3 stage ring counter using D flip flops. I want to initialize the 7474 chips so that one stage is high and the other two are low. I tried to use a resistor and a capictor. Is there an easy way I can modify my circuit so that it will work? All three of the lights turned on, instead of red then green then yellow, as desired.

Thanks,
Matt

 

[BobK]

A 4017 is a good choice for making traffic lights. You can find lot's of designs on line.

Bob

 

[MattCAnderson]

Thanks for the input, Bob.

I believe I understand ring and johnson counters, as described by wikipedia -

http://en.wikipedia.org/wiki/Ring_counter

I found a schematic online and will try another design -

http://electronicsclub.info/p_trafficlight.htm

Matt