What does it mean when my radio says SITE TRUNKING?

If a significant failure caused the radio tower sites to lose their connection to the master site (possibly due to a zone controller failure), they can operate independently in “site trunking” mode.  Users will be able to communicate between towers but will be unable to reach a dispatch center console.  The radio display will alternate between “SITE TRUNKING” and the name of the selected talkgroup.

Dispatchers will receive an audible alarm on their PSAP backup control station radio, prompting them to turn on portable radios.  Their consoles will not be able to use network talkgroups during site trunking mode.