Just was on both Amtrak trains 19 and 20 this week, Tye River is where the "radio district" changes in NS in Virginia. South of Tye River 160.905 for road channel, North of Tye River 160.950. Tye River is roughly halfway between Lynchburg and Charlottesville.
What I found unusual, in the past when riding on Amtrak engineer and conductor would via radio acknowledge change of channel when crossing from one district to another and from railroad to railroad, on both trips this week they did not do that...so there I was listening to 160.905, passed Tye River going North and no longer was hearing the crew calling signals, the dispatcher, or defect detectors...checked radio to make sure it was still working then set it to scan and picked up the crew on 160.950...
Returning South I played extra attention to where the changeover occurred...and as we approached Tye River sure enough no acknowledgement of channel change...