I believe this goes here.... FYI -- I came across this on the NS website and thought it was interesting (if not confusing for someone like me who is not well versed in railroading operations). http://www.nscorp.com/content/nscor.../communications-and-signals-then-and-now.html
Thanks for posting, a very good presentation of signals past and present. I applied to the Signal Department opening NS has in Decatur IL as I have always enjoyed working on electronics.
Nice summary of signal history. Done so the lay-person can easily follow. ACI labels. There's a bad memory. Hours and hours of fiddling with those. What a pain in the posterior. If they weren't perfect, all too often,..............