Getting back to the FYA idea, I know that the downfall with bi-modals is color blindness, but when you thing about it, it's a non issue w/ FYAs. If it's green, it'll always be steady, and if it's a flashing yellow, it'll always be flashing, as the yellow arrow to indicate the light is turning red has it's own section above the bi-modal, so color-blindness doesn't really apply with these signals.
"Driving a car is like making love. In both cases, a mirror makes objects appear larger than they really are." - Sophia Petrillo
Sorry to dig up this old thread. Probably better than posting a new topic though.
Charlottesville's Bimodals The city of Charlottesville uses no doghouses, only 4-sections with bimodal arrows. They are all LED, except for 1 remaining fiber-optic arrow that is currently not functional. All (or most) of the older LED bimodals are PSC. All of the newer ones are different, I don't know what the brand is. The PSCs have clear, smooth, rounded glass, and the new modules have frosted, textured, flat glass. There are separate yellow and green LED filament lights next to each other, and those sets repeat to form an arrow, making two overlapping arrows. Here is a compilation video of a PSC bimodal arrow: http://www.youtube.com/watch?v=zpN-sp0RhS0
Then there are some redundant bimodal arrows. A few 3-section signals had the green arrow fitted with a bimodal, but didn't have the middle yellow abandoned. The two yellows are lit at the same time. There are also a few 4-sections w/ bimodals that cycle as a normal R-Y-G-GA signal, so both yellows are lit at the same time also. I have videos of all of the 3-section signals, but none of the 4-sections. Here is one: http://www.youtube.com/watch?v=EnGkEztnq7Y
An interesting company Awhile ago, I saw a regular 12" 1-section signal with a red X and green ↓ being used for monorails in Disney World. I searched for a while and found this interesting company. They make traffic signals that appear to be made from CH R molds. http://www.lanecontrols.com/ They make many LED multi-indication 1-section signals (In 8" & 12"): O / O / O X / O / ↓ X / X / ↓ X / ↓ ← / ← ← / O ← / O ← / O
They offer regular signals too. They also offer blue and violet LEDs...
The "newer module type" looks like a Leotek to me. I once had a Leotek 12" green arrow module that had the same style lens as the bi-modal in this video. I actually like this style, as it appears to be an incandescent-look style module where you can not see the individual LEDs, and there is no change in the arrow's position when the color changes from green to yellow.
-Jeff
"The Walk Sign is on for all Crossings" -Polara Navigator Pushbutton