J JonMyrlennBailey Active member Sep 2, 2018 #1 What are the blue lights and loudspeakers on the sides of some relay boxes? What are they called and what purpose do they serve?
What are the blue lights and loudspeakers on the sides of some relay boxes? What are they called and what purpose do they serve?
R RHKluckhohn Active member Sep 2, 2018 #2 I've noticed those occasionally. I don't know, but suspect some sort of failure alarm/alert system. Or perhaps they're a Railway Police pursuit vehicle in disguise? :B~D
I've noticed those occasionally. I don't know, but suspect some sort of failure alarm/alert system. Or perhaps they're a Railway Police pursuit vehicle in disguise? :B~D