Dave Hoyt (who is a retired radio tech for the State of New Mexico), Cal Smith, and I did extensive radio reception testing for the C&TS last summer. More about that in a minute.
First, cellular technology. With the exception of satellite cellular (very expensive) most cellular transmits in the 900 mHz band (UHF) at low wattage. As such, and by design, cellular signals don't travel as far as far as VHF signals (what the 160-161.565 mHz railroad spectrum uses)--so one "cell" site does not interfere with another. In mountainous, sparsely populated areas, building lots of cell sites isn't financially practical for carriers, so coverage is spotty. Thus, the "dead spots." Also, with the exception of Nextel, currently a "bit player" in the Colorado cell network, a "two-way" feature is unavailable, which makes cell communications that "mimic" two-way radio for "regular" railroad work basically impractical.
The important thing for the railroad is to have reliable radio coverage that covers the full line and is "open", so trains can talk to the dispatcher, maintenance of way personnel, other trains, stations, etc. at will. The current radio system the C&TS has is not bad, but it has several nagging "dead spots", particularly around Toltec Gorge. Dave and I studied this last summer and have made recommendations to the railroad about possible solutions. Like anything else, they tend to cost money, not a plentiful commodity on the C&TS these days. However, I think that upgrading the railroad's radio system is a worthwhile project and I assume it will be pursued as resources are available.
I could spend a couple megabytes in detail, but suffice it to say that it will be some time (if ever) before reliable cell-service comes to every nook and cranny of the C&TS. In the meantime, the C&TS's current radio system, with some upgrading, will serve it well for the foreseeable future. Oh, by the way, if anyone is wondering, I hold both an amateur and a business band radio license, so I've been around this stuff for a while.
