Hi there all in Chicago area...Chicago13 is correct on PD detail units. I flew back from Hawaii last week, was standing next to an officer, and heard dispatch call "7221", which he was. Then, I powered up my BCD346XT, with Chicago O'Hare programmed in this week, and heard multiple times, 7200 units dispatched on the trunked side for baggage check, canine officer request, etc..