“Sarah, get me the courthouse.”

The sharing of a small number of radio channels between a large number of users 123 Voice Channels

Talkgroup Individual users can be combined into collections called They are made up of a collection of users who typically need to communicate in order to accomplish their job..

Compare a trunked communication system to the system many airlines use. Any agent can handle a transaction for any user. Each user is handled by the next available ticket agent.

It is improbable that a large percentage of users will want to make a call at the same time. Most conversations are relatively short. If there are more users than ticket agents, a single queue builds up. The single queue gives all users equal access to the available ticket agents.

A Motorola trunked radio system also uses a that functions like a traffic that functions like a traffic officer and controls the operation of the trunked repeaters.

A series of trunked repeaters Operation and Assignment of the Control Channel - Who? - What? - Where?

Step 1: Central Controller Receives a Call Request

Step 2: The central controller assigns one of the idle repeaters to the user’s talkgroup. In this case, Repeater 5 is assigned.

Step 3: All radios monitoring the control channel receive the transmitted message.

Step 4: All of those radios assigned to the talkgroup associated with the Talkgroup ID switch to the assigned voice channel frequency. Voice

Step 5: When the call is completed, the radios in the talkgroup switch back to the control channel frequency. The previously assigned voice channel now becomes available for other calls.

The Prime Site has lost communication to the central controller. Radios operate as they would in a normal trunking environment, except, if there are other entity sites in your system, the radio user will not be able to communicate with radios that have roamed outside their home system. Communication with your dispatch center may be limited. The radio may be programmmed to emit a tone every 6 seconds. every 6 seconds. NOTE: Multiple individual sites = one site for site trunking

Major Failures: - Central Controller - All Four Control Channels - All Voice Channels Radios operate as they would on a conventionalRadios operate as they would on a conventional repeater system Low level alert tone every 10 secondsLow level alert tone every 10 seconds