I've been a full scale railroading fan since I could remember, with visits out to the railroad with my father. Growing up, I was never more than a few miles from the Santa Fe in Inglewood, CA, and even was able to hitch rides in locos with friendly crews on rare occasion. One time back in the late 60s, I caught a ride with a crew at El Segundo station in what I think was a GP-30 or 35. They took me into Manhattan Beach for lunch, then back up into Inglewood to switch some cars. Returning south (railroad west) on the Harbor Branch we crossed over the grade crossing at Manchester Blvd in Westchester and discovered someone had laid a telephone pole across the tracks. Throwing the train into emergency, we slammed into the pole at probably 20 mph, snapping it in half and knocking it well off the tracks. For a 12 year old in the fireman's chair, it was loads of fun and a great way to spend the afternoon.

Now that I'm in Arizona, the distance to serious transcon railroading has never been shorter with the UP mainline only an hour south and the BNSF transcon as little as two hours north in Flagstaff. I've become interested in the wireless signaling that the BNSF uses, called ATCS (Advanced Train Control System). There's a freeware program called ATCSMon that when connected to the appropriate scanner or other receiver allows you to decode some of the information that is transmitted over the air. On the BNSF, it's stuff like signal indication, track occupancy, and switch position. With Track Builder software from Signal Consultants, I've been able to construct a real dispatchers' display just like the BNSF might use and watch the trains as they roll across northern Arizona.

Closer to home is the Union Pacific Railroad. While Phoenix is the largest metropolitan area in the United States to not be served by a mainline railroad (the best we get is to be at the end of UPRR's 72mi TWC, single-track spur), the UP mainline is about 25 miles south, approaching Phoenix at its closest around the farming village of Maricopa. This is the old Southern Pacific Gila Main, and is a very busy piece of single-track railroad which is now undergoing the conversion to two main tracks.

UP runs ATCS over the entire length of the line from Yuma AZ to just west of El Paso TX, but in typical UP style, sometimes way different than everyone else. From Yuma to Stockham E (in northwest Tucson), UP uses industry-standard ATCS on VHF AAR channels. From South Yard in Tucson to Raso station, about 8 miles east of Willcox AZ, it's using the UP ATCS pair 896.8875/935.8875MHz. And finally, from Bowie AZ to the Texas state line, it switches back to VHF channels again, using some of the same channels as before, with a few new ones as well.

I run several ATCSMon servers with the help of a bunch of friends without whom it wouldn't have been possible. Right now, the combined coverage of the BNSF includes a receive site at Parks AZ, which gives coverage from well west of Williams AZ to the Arizona Divide; Winslow AZ, which hears from east of Flagstaff to about Holbrook; and Clovis NM, which isn't in Arizona at all %^), which gives coverage from about Melrose NM into Texas. On the UP, there are remote receive sites at Yuma, AZ; White Tank Mountain (west of PHX); Pinal Peak (east of PHX); Tucson AZ; and Benson, AZ. We'd always like to add more sites. If you happen to live somewhere near one of these railroads, have a halfway decent location for receiving the transmissions, and have fulltime internet connectivity, please drop me a note at jon (at) jonadams (dot) com.

The UP ATCS-equipped control points, running east from Tucson, are as follows:

The SPRR's Yuma District is well documented in this previously unpublished treatise, dated from about 1990. At the time, I was spending every other weekend somewhere along the SP's Yuma District lines, anywhere from West Colton to Yuma. This stretch is now part of the Union Pacific Railroad's Los Angeles and Tucson Service Units. It provides a nice historical point of view on the present Sunset Line stretch from the classification yard at West Colton CA all the way to the east end of the East Yard in Yuma AZ, as well as some useful information on the branchlines that were at that time still operating within the old Yuma District.

The Southern Pacific Lines: The Yuma District - A Guide to Desert Railroading
(Also Titled "Hot Rails to Hell - The Southern Pacific in the Colorado Desert")

Copyright © 2014 Jon Trent Adams
jon (at) jonadams.com