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Testing the Sequencer
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Here's a pic of the sequencer that I made for my traffic signal being tested before I install it into the signal.
The sequencer is pretty simple, it contains a 555 timer and a 4017 decade counter. The 555 timer sends out a pulse at a regular intervals (the interval can be adjusted using a potentiometer) to the 4017 which then outputs the count in binary. To convert this into a three light control diodes were used to combine the outputs into one suitable for a three light signal. Also the diodes were arranged such that each light is on for a different amount of time (ex amber is on for 1/10 cycle, red for 5/10, green for 4/10). The counter is set up to reset every 10th cycle so the cycle can repeat itself.
This output from the 4017 is fed to three relays which switch on/off the red amber and green sockets. The time is semi adjustable, the total length of the sequence can be adjusted but the proportion of time each light is on can't be changed without changing to the two times.
A microcontroller such as a an Arduino should be able to have independent timing, along with supporting extra features such as flashing green left turns, and pedestrian signal control. Also the relays can be replaced with TRIACs or solid state relays (SSRs) to have silent switching.
It is shown installed in my Econolite Signal here:
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![Testing the Sequencer
Here's a pic of the sequencer that I made for my traffic signal being tested before I install it into the signal.
The sequencer is pretty simple, it contains a 555 timer and a 4017 decade counter. The 555 timer sends out a pulse at a regular intervals (the interval can be adjusted using a potentiometer) to the 4017 which then outputs the count in binary. To convert this into a three light control diodes were used to combine the outputs into one suitable for a three light signal. Also the diodes were arranged such that each light is on for a different amount of time (ex amber is on for 1/10 cycle, red for 5/10, green for 4/10). The counter is set up to reset every 10th cycle so the cycle can repeat itself.
This output from the 4017 is fed to three relays which switch on/off the red amber and green sockets. The time is semi adjustable, the total length of the sequence can be adjusted but the proportion of time each light is on can't be changed without changing to the two times.
A microcontroller such as a an Arduino should be able to have independent timing, along with supporting extra features such as flashing green left turns, and pedestrian signal control. Also the relays can be replaced with TRIACs or solid state relays (SSRs) to have silent switching.
It is shown installed in my Econolite Signal here:
[url=https://dl.dropboxusercontent.com/u/102661519/Lighting/GoL_Pics/Deleted%20Pics/100_2120.JPG][img]https://dl.dropboxusercontent.com/u/102661519/Lighting/GoL_Pics/Deleted%20Pics/normal_100_2120.JPG[/img][/url]
Keywords: Traffic_Lights](albums/userpics/normal_100_2089.JPG "Click to view full size image
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Testing the Sequencer
Here's a pic of the sequencer that I made for my traffic signal being tested before I install it into the signal.
The sequencer is pretty simple, it contains a 555 timer and a 4017 decade counter. The 555 timer sends out a pulse at a regular intervals (the interval can be adjusted using a potentiometer) to the 4017 which then outputs the count in binary. To convert this into a three light control diodes were used to combine the outputs into one suitable for a three light signal. Also the diodes were arranged such that each light is on for a different amount of time (ex amber is on for 1/10 cycle, red for 5/10, green for 4/10). The counter is set up to reset every 10th cycle so the cycle can repeat itself.
This output from the 4017 is fed to three relays which switch on/off the red amber and green sockets. The time is semi adjustable, the total length of the sequence can be adjusted but the proportion of time each light is on can't be changed without changing to the two times.
A microcontroller such as a an Arduino should be able to have independent timing, along with supporting extra features such as flashing green left turns, and pedestrian signal control. Also the relays can be replaced with TRIACs or solid state relays (SSRs) to have silent switching.
It is shown installed in my Econolite Signal here:
[url=https://dl.dropboxusercontent.com/u/102661519/Lighting/GoL_Pics/Deleted%20Pics/100_2120.JPG][img]https://dl.dropboxusercontent.com/u/102661519/Lighting/GoL_Pics/Deleted%20Pics/normal_100_2120.JPG[/img][/url]
Keywords: Traffic_Lights")
how many seconds are the individual color phases and is it adjustable?
@Jace, Here's the circuit I found online that I based mine on with some changes, I removed the connection to pin 10 on the 4017 counter so it doesn't show the yellow phase before the green phase and I substituted the 22K resistor between pins 6 & 7 on the 555 timer with a 35K potentiometer so I can change the timing. I also added transistors and relays to control the 120V incandescent lamps too. I'll post a schematic for you sometime tomorrow. btw, your friend seems awesome.
A basic microcontroller that should work with this and is pretty user friendly to program is a Arduino. You'll have to get them from a electronics supply place or order them online since I doubt RS still carries a lot of electronic parts.
Oh and I've actually been looking for one of those fibreoptic ped signals and turn arrows too. Ontario used to use the turn arrow a lot before LEDs came in.
I'm guessing I'd likely have to either have one custom ordered or find someone that's handy with circut boards then if i ever get a ped signal and 12-12-8 crosswalk signal.