It probably has a lot to do with the cost and weight of the old five section lights compared to a four section light with a fiber optic arrow (not to mention that the fiber optic arrow is probably more energy efficient than an incandescent arrow).
Most of the new installations in Oregon have a bi-color green/yellow LED arrow with an yellow arrow above it. It will change from green to the upper yellow (since a position change is required for the color blind), then after a few seconds, the lower arrow will flash yellow.
I have seen traffic lights in Ontario that the left turn signal actually flashes. Pretty strange but cool hehehe
Weird things involving green lights: In some parts of Canada, a protected left turn is indicated by a flashing green light (not an arrow) with or without a steady red. In other parts of Canada, signals change to flashing green at night, rather than flashing amber. In many parts of Mexico, the green light will begin flashing a couple of seconds before the yellow comes on as an additional warning. In northern Indiana, the MONON railroad had a unique system for warning drivers of approaching trains at grade crossings: a single green traffic light which stayed lit except when a train arrived. No light meant stop. Sadly, all of these were removed a few years ago.
Heh, thats pretty crazy. I remember back in Glen Rose, TX, the traffic lights had two reds that would both be on at the same time. Pretty odd...
Those are also quite common in northern California. Unlike Eclipse sirens, of which northern California has none that I've seen.
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