. "The bell sensor system 90 includes a sound producing device such as a bell or speaker horn 92 such as CSI/Speco model number SPC-8, bell sound emulation circuitry 94 for operating speaker horn 92, a printed circuit board 96 for supporting circuitry 94, and a mounting arrangement 98 for supporting the system 90 on a support structure such as a grade crossing signal post 10." . . .