
Design complications
Curious as to why there are so many suggestions of adding an additional light (colour)
There are already 3^3 options (Red, amber, green. On, off, flashing) shirely it would be much easier to implement one of the existing options onto the existing equipment?
Yes, I've seen counters (not always true seconds though), flashing red or green when about to change, and also amber and red or amber and green. So they are all possible and already in use.
So why the jump to making it even more complicated?