It would seem that type of instrument would be prohibited by Amtrak from being carried on board.
Plan ahead before you arrive at the station. Many items many not be transported on Amtrak trains.
www.amtrak.com
Since many Amtrak stations are open platforms, with or without shelter, there is no current method preventing anyone from carrying onto a train anything that can fit in luggage.
Some years back, some bright person* decided my local Amtrak station building needed to have TSA personnel interrogate/frisk/impede passengers on the grounds of "safety". I said in a moderately loud voice that their checking for bombs is useless, as anyone who watched old WW2 movies could tell you the best way to sabotage a train is to blow up the bridge. Said TSA presence lasted more than a year but did finally go away.
I don't know if any other stop with a station building had TSA personnel because the other end of my monthly travels was an open to the public cement slab, er, platform.
*My personal take was that someone at TSA said it as a joke and a clueless management type who never traveled anywhere took it as a great idea. At least they got rid of it after awhile.