I put mine in carry on, in a large clear ziplock bag with the wall wart, cell phone and cell phone wall wart. I also have a laminated copy of my Ham license attached to the scanner. None of them have given it a second look, or turned it on or even asked about it. With all the other electronic stuff that goes thru I guess the scanner is not a big thing.
A friend was ripped off by 2 TSA people, while he was trying to stop one fron damaging his camera gear, the second one took $400.00 cash while checking his wallet.