Depending on your antenna you should be able to hear the frequencies for each Dispatch Centers depending on the tower they are on. In my car I usually start picking up FDNY around Kingston depending on the weather, and have them (scratchy) until around the DMB.
South Jersey...try 154.190, 154.370 and 154.430...those are Staten Island, Brooklyn, and Citywide respectively. If you have a scanner with PL, use PL 186.2, and see what happens.