PTC is a system that is heavily dependent upon software and communications. When mandated by Congress, there were a few systems in use (including part of the NEC) but what was mandated only existed in theory. Congress also failed to set aside the necessary bandwidth for the railroads, forcing them to compete on the open market. I guess the FCC finally stepped in under pressure to find the railroads enough bandwidth in urban areas where there is too much competition with cell carriers.

The whole antenna thing I don't think involved trespassing on private property. All the PTC installations I have seen have added an antenna to update an approaching train of the signal/switch status, so apparently an antenna is required at every signal case involving a switch or signal. Everything stopped for a year when it was discovered that the FCC requirement for sighting these antennas, on the railroad right of way next to the existing track, all required an archaeological review to determine if they might be disturbing any Native American artifacts. Now add delays with the FRA trying to make a decision, supplier issues (something like 22 different components), an arbitrary deadline, and the FRA threatening fines starting January 1 - it isn't hard to figure out why the railroads are at a loss on what to do despite having already spent BILLIONS. From what I have heard, the few sections being tested have been problematic with test trains being stopped by a penalty application for no reason, so it may take years to get the software to work right.

It is strange that the railroads haven't really complained too much about the cost. I wonder if the PTC costs will be primarily allocated against Amtrak/commuter and TIH shippers or if everyone will share the pain? And I have no doubt that it will be used as an excuse to go engineer only within a few years.

The only constant is change - but it doesn't mean I have to always like it.