I live in Miamisburg. Miamisburg PD is on the Montgomery County Trunked System. They are dispatched by Sheriff's Office on talkgroup 144 SO SOUTH. They identify simply as Miamisburg ###.
Miamisburg and Miami Township combined their fire departments a few years ago into the Miami Valley Fire District. They are dispatched on talkgroup 13232 RDC 1 as Stations 50-55. I suggest that you click on the "Wiki" tab from the county page. It contains all the information you are looking for.