Abstract: An anchor RS acts as the single interface between the switched telephone network and the wireless communications system throughout an entire call, even if the subscriber unit travels to different radio systems during the call. This allows (1) the signaling to set up the connections between the anchor and target RPCUs; and (2) the maintenance information for the call to remain in the anchor RPCU, which is connected to the original switch. This avoids tying up network switches with exchanging signals and call maintenance information about service features, thus resulting in a substantial "savings" in valuable telephone network resources. Also, existing switches do not need to be replaced or reconfigured to accommodate this hand over method.

Abstract: Described are preferred pitches which comprise a blend of coal tar pitch, petroleum pitch and gilsonite pitch, and preferred processes and compositions which can be used to form such pitches. The pitches have substantially reduced contents of polyaromatic hydrocarbons (PAH's) relative to standard coal tar pitches, and are thus more favorable from health, safety and environmental standpoints.