There are so many ways of sensing something like a train going by that it is impossible to eliminate the ability to do that. Many of these devices are available for Car and home security and any hobbiest could come up with ways of there own. The scary thing here is that someone was actually setting up a device to sense the train. Well maybe it is just someone who lives near by and rides the train every day and wants a heads up when the train is arriving...Never know. Kind of like not wanting to miss the bus. Probably not so innocent though- with everything going on like it is.
I just finished reading "Memorial Day" a novel by Vince Flynn. Recommended reading for all TM Freepers. It's an easy read. I finished it in two days, reading off and on. It's about a planned terrorist attack on D.C. It's very plausible! Rush L mentioned on his show that he was reading it and also recommended it. I hope that we have heros in real life that know what the heck they are doing like they do in the book.
I suspect the device on the tracks was in a heavy industry area near the oil refineries.