I believe that it's broken down as follows:
100 series - North Precinct - Old Allen Sta.
200 series - South Precinct - Raines Road Sta.
300 series - East Precinct - Mt. Moriah Sta.
400 series - West Precinct - Union Ave. Sta.
500 series - Central Precinct - Tillman Sta.
600 series - Downtown Precinct - S. Main Sta.
700 series - Airways Sta. (might be incorrect on the name)
800 series - Northeast Precinct - Appling Farms Sta.
900 series - Southeast Precinct - Ridgeway Sta.
For the ward numbers, here's the breakdown. X99 would be desk officer, X00 the commander, and the first few numbers (e.g., X05, 06, etc.) would be shift lieutenants. Alpha, bravo, charlie, and delta refer to the shift, which allows some overlap. Signal C refers to end of shift for a given watch.
Looking at the wards, there might be 3 or so units patrolling a ward at a given time. For example, the ward number (e.g., 122) would be a two man car. But there also might also be a 152 and 182 on duty as well. The middle number refers to seniority, so 182 would be the senior officer in the 122 ward.
I'm not sure how K-9, aviation, mounted patrol, and harbor patrol are numbered, nor which talkgroups those officers use. I heard that all investigators are on the Union Ave. Sta. Tango units are traffic, and kilo are K-9. Not sure about tact squad.
Admin units (department-wide) are in the 1000s.
Special units (assigned by precinct) are 6000 and 8000 units (e.g., 8312, a special unit assigned to the Mt. Moriah Sta.) I don't now whether the last two digits correspond to the ward or whether the unit is station-wide.
Good luck with your listening. I just got back into scanning....j c
