[dinasour]

I use a couple of these things around my house

So do I. They work quite well. And would definitely be triggered by a train passing.

This is scary. I can't think of a darned reason why someone would do this, other than to trigger something.

[SOSCEO]

This is scary. I can't think of a darned reason why someone would do this, other than to trigger something.

I agree. The ones I use even have two sets of terminals on the receivers for connecting "normally open" or "normally closed" relays. They do have wall wart transformers, but they are 9 volt 100mw and could easily be wired to a battery. A 4th grader could easily rig something up to blow up a firecracker when someone walked by and so could someone else with more sinister intentions.

There would be no other reason something like this would be planted by a train track. I generally take reports of "suspicious" things found here and there with a certain degree of skeptisism, but this report immediately struck me as something that could be much more that it appeared. It could be series.