160.950 - NS Road
160.245 - NS Train to Dispatcher
160.830 - NS Dispatcher to Train
(I may have these two reversed. Probably 80% of the dispatcher to train radio traffic is on the road channel, they just use the dispatcher channels for track warrants, speed restrictions, etc.)
160.680 - Georgia Central
160.800 - Georgia Central
Amtrak doesn't have service to Macon. It runs in/out of Atlanta through the old Southern mainline between Washington DC and Birmingham, AL. They use the normal NS road and dispatcher channels while operating over NS.