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County of Kauai P25 System is no longer comprised of just 7 frequencies for each department. It's now comprised of multiple control channels and voice channels throughout 3 antenna sites around Kauai that provide coverage to all agencies throughout Kauai. 


So the question asked what is the difference between Talkgroups, Control Channels, and Voice Channels? 


Control channels:

In essence, a trunked radio system is a packet switching computer network. Users' radios send data packets to a computer, operating on a dedicated frequency — called a control channel — to request communication on a specific talk-group. The controller sends a digital signal to all radios monitoring that talkgroup, instructing the radios to automatically switch to the frequency indicated by the system to monitor the transmission. After the user is done speaking, the users' radios return to monitoring the control channel for additional transmissions.

This arrangement allows multiple groups of users to share a small set of actual radio frequencies without hearing each other's conversations. Trunked systems primarily conserve limited radio frequencies and also provide other advanced features to users.



A talkgroup is an assigned group on a trunked radio system. Unlike a conventional radio which assigns users a certain frequency, a trunk system takes a number of frequencies allocated to the system. Then the control channel coordinates the system so talkgroups can share these frequencies seamlessly. The purpose is to dramatically increase bandwidth. Many radios today treat talkgroups as if they were frequencies since they behave like such. For example, on a radio scanner, it is very common to be able to assign talkgroups into banks or lock them out, exactly like that of conventional frequencies. (Example: The system detects MPD Officer communicating to MPD Dispatch from Kihei  showing the ID tag of MPD - Kihei with a radio ID tag of that user's radio.)


Radio ID is the assigned number of that radio that is programmed into the system identifying what agency it belongs to and who is it specifically assigned to. (Example: 8001001 is the Radio ID for HPD Dispatch console in Hilo)



*Note: We do not suggest you buying an off-hand digital radio (Motorola, Tait, etc.) as a scanner and if you do, there are legal implications behind it, even if it's only strictly for listening purposes only. It emits a signal and radio ID where radio maintenance personnel can turn that signal off once detect as an unauthorized Radio ID and may lead to legal persecution and fines under state, county, and federal law if caught. 

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Control Channels and Voice Channels for each 3 Antenna site. 


When setting it up in a program software: 

Must list all 3 sites with the control channels listed in order for the system to work on your scanner. 

Once you complete that step, then you can set up the TGID into the system. (Without the TGID, your system will not pick up any transmissions until programmed)

Still confused?

Feel free to drop us a line and someone will provide one-on-one support to help you set it up.

Or feel free to use the form on the Contact Us page and one of our programmers will contact you to provide help and support.​

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