Patent ID: 8755788

Claim:
In a two-way radio frequency (RF) communications system having at least one fixed terminal, one or more channels, and a plurality of subscriber units, the method comprising, at a first device: receiving, from a first subscriber unit out of the plurality of subscriber units, an alert tone request identifying at least a type of alert tone associated with a particular event or condition and at least one destination associated with the event or condition selected from (i) an identity of a radio site at which to alert subscriber units out of the plurality of subscriber units that are currently operating at the radio site, (ii) an identity of a plurality of radio sites, but not all radio sites in the RF communications system, at which to alert subscriber units out of the plurality of subscriber units that are currently operating at the plurality of radio sites, and (iii) a system-wide destination including all of two or more radio sites in the RF communications system; and causing one or more fixed terminals corresponding to the radio site or sites identified in the alert tone request to instruct subscriber units currently operating in corresponding coverage areas of the one or more fixed terminals to play back a locally stored or generated alert tone corresponding to the type of alert tone identified in the alert tone request at each subscriber unit.