Just got curious about something! I bought an old EFJ P25 radio for amateur use and it came from Arizona as part of an interoperability solution. Since I live in north DeKalb county and am in shouting distance of 3 P25 public service systems, DeKalb County, Fulton County, and City of Atlanta, do all these guys respectively have an Interop channel programmed for one another? I haven't checked the frequencies in the database but I think they are all different! Just curious, I knew there was a big effort at standardization after 9/11.