traffic light no ICs

Thread Starter

dirge4Dslain

Joined Nov 13, 2013
1
could anyone help me with this take home exam of mine? my proff said that we should research and ask on how to create traffic light with no ICs.. and since he doesn't even teach us he just give out projects quizzes and exams.. well usually i could do it.. but this traffic light schematic do without ICs..
first red LED light should be on for 5 sec.. then off and yellow LED light should turn on for 3 sec.. then off and green LED light should turn on for 2 sec.. then back to red LED light.. and plus there should be a DC motor that would stop turning at red light... spin slowly at yellow then spin at max speed at green...
oh.. and the DC voltage is a 4.5V cell pack
thank you...
 

WBahn

Joined Mar 31, 2012
30,076
Time delay relays.

Or just have a motor with a turn a wiper that takes ten seconds per revolution and have it contact three different strips of the appropriate length or have a cam (or cams) that close different switches as it turns.
 
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