xpawel15x said:
Okay thanks for identifing these for me. But I'm hearing these on Troop B... I thought it's impossible to hear Troop A talkgroups on Troop B.
Dont forget that the system is a smartzone (someone correct me if i'm wrong)
SmartZone Operation
As much as trunking solved traffic handling ability and simulcast improved wide-area operation, some limitations prevented this from being the panacea we hoped for. Trunking has a limited number of frequencies it can handle (limiting the amount of traffic it can carry). Simulcast has a limited number of sites it can handle (limiting the amount of signal delivered to the coverage area- with larger areas getting less signal for a given number of sites). Simulcast requires a transmitter at every site for each frequency whether or not that site is required for a particular call (increases the system cost), and requires exclusive frequency usage in a very large area (limiting the ability to reuse frequencies- an FCC issue). So we once again turned to the computer to solve these problems and increase the geographical coverage.� Motorola responded to our needs with a system called �SmartZone� (also a Motorola registered trademark) which takes two or more �Smartnet trunking� systems (any combination of simulcast and non-simulcast) and ties them together with a master computer called the Zone Controller. Smart Zone allows us to combine the good points of both single site and simulcast trunking to achieve a better overall system. The job of the Zone Controller is to keep track of every radio in use, what site it is using (from the Zone Controller perspective, each entire simulcast �sub-system� (no matter how many remote sites it has) is called a site and treated as one site), and what talk group that radio is switched to.� When a radio is turned on it affiliates with the system, reporting its ID, site it is on, and talkgroup selected. When a user keys a radio, or changes the channel selector knob, the radio talks to the site it is affiliated with, which in turn passes the information (desire to talk or change of talk group) to the Zone Controller.� The system thus knows which sites (remember an entire simulcast sub-system is just another site as far as the Zone Controller is concerned) require the audio for a particular talkgroup. In the case of PTT (Press To Talk or keying the radio) activation, the Zone Controller then tells all affected site controllers to make a channel available, and ties the audio of these sites together to complete the call. The individual site controllers then (via the control channel) tell all of the subscriber units with the talkgroup selected which frequency to listen to. All this happens in less than half a second.
