Uniden BC898T manual Types of Trunking Systems, Motorola Trunking, Edacs Trunking

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Types of Trunking Systems

Trunking systems divide a few frequencies among many different users, but the way that each system does this is slightly different. This section describes some of the technical data behind Motorola, EDACS, and LTR trunked radio systems.

Motorola Trunking

While there are different types of Motorola trunking systems, they all use the same basic trunking method. The system consists of one control channel plus one or more voice channels (typically 10, 20, or 30 total channels). When a user presses Push To Talk (PTT) to transmit, their radio first sends their talk group information to the control channel. The computer then assigns that talk group to a specific voice channel and transmits that data over the control channel. All radios in that talk group switch over to the assigned voice channel and the user can begin speaking. This all typically takes place in about a second...the person transmitting hears a beep from their radio when the channel is assigned and then it is OK to start talking.

The systems in use are:

Motorola Type I – the radios send the radio ID, the fleet and subfleet talk group ID to the control channel each time they transmit. To program a Type I system, you need to know the system’s fleet map. The most common fleet maps are included at the back of this manual. You can also find fleet map resources on the web.

Motorola Type II – the radios only send the radio ID and radio channel code to the control channel. The central computer keeps a database of radio ID’s and which talk group is assigned to which channel code for each radio, so with this system the user’s radio sends

only about 1/3 the data as a Type I system with each transmission. Type II systems do not use Fleet-subfleet talk groups; instead they use a 5-digit ID for each talk group.

Type IIi Hybrid — these systems support a mix of both Type I and Type II users. Like Type I systems, you must know the system’s fleet map to ensure proper tracking.

EDACS Trunking

EDACS trunking works in much the same way as Motorola trunking with a couple of major differences. In an EDACS system, each frequency used by the system is assigned a Logical Channel Number (LCN) so that less data needs to be transmitted by the control channel. Also, talk groups are assigned in an Agency-Fleet-Subfleet (AFS) hierarchy. Also, there is one variation of EDACS called SCAT that your BC898T can monitor.

Logical Channel Numbers – each frequency used by the system is assigned an LCN. This information is programmed into each user radio. When a user presses PTT, their radio sends their AFS information to the control channel. The computer then assigns that talk group to a channel and sends the LCN so that all other radios in that talk group will switch to the correct channel. To program an EDACS system in your scanner, you will need to

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Contents Page Precautions Earphone WarningBC898T Controls and Display Contents Page FCC Wants You to Know Scanning LegallyFrequency Range Steps Mode Transmission IntroductionFeature Highlights About This Manual What is CTCSS/DCS? What is Scanning?What is Searching? Understanding ScanningConventional Scanning Ctcss Frequencies HzRepeater Operation What is Trunk Tracking?Simplex Operation Trunked Scanning Edacs Trunking Types of Trunking SystemsMotorola Trunking LTR Trunking Information On The Internet Where To Obtain More InformationUsing a Computer to Control Your BC898T Frequency Guide National Public Safety Included With Your ScannerInstalling Your Scanner For Home Use Desktop InstallationAdapter Safety Feature Using An Optional External Speaker/Earphone/HeadphoneUsing An Optional Tape Recorder Listening SafelyUsing the Demo Software Installing The SoftwareConnecting the DC Power Cord Installing The Scanner In a VehicleConnecting the Antenna Plug Installing a Temporary Power CordInstalling a Permanent Power Cord Basic Operation Setting the SquelchUsing the Rotary Tuner Turning On the ScannerManually Selecting a Channel Using the Frequency/Channel Mode SelectorUsing the Lock Key/LED Scanning Programmed ChannelsRestoring All Locked Out Channels Locking/Unlocking BanksLocking/Unlocking Channels Priority ScanningUsing the Dimmer Trunk Scanning OptionsSetting the Attenuator ID LockoutSearching Tips ID Delay ModeID Hold Mode Restoring a Single IDID Monitor Mode Scan ListsHolding On An Active Frequency SearchingChain Search Storing Found Frequencies Setting Data SkipSkipping Frequencies Setting Subaudible Tones for Searching Automatically Storing FrequenciesSearching a Trunked Bank Setting Delay For All Search RangesAttenuating All Search Ranges Searching for CTCSS/DCS Tones Searching for a Weather Broadcast Using Weather Alert SameTurning Weather Alert On/Off Programming a Fips Code DsscccPage Transferring a Frequency to a Specific Channel ProgrammingTransferring a Programmed Frequency Programming a Channel With a CTCSS/DCS Tone Duplicate Frequency AlertDeleting a Stored Frequency Setting Delay in Manual Mode Setting the Delay ModeSetting Delay in Scan or Search Mode Programming TipsFrequency Skip Recording TransmissionsData Skip Changing the Frequency Step Setting the Modulation ModeProgramming Conventional Channels Setting Priority Channels Programming Motorola Systems Setting the Scanner to Trunking Programming ModeProgramming Trunked Systems Programming Channels and Entering Trunking FrequenciesProgramming Fleet Maps Selecting a Preset Fleet Map Programming Talk Group ID’s Programming a Hybrid SystemProgramming Edacs Systems Programming LTR Systems Care and Maintenance Troubleshooting Edacs Edacs Specifications Page Optional Accessories Appendix Preset Fleet MapsPreset Map Preset Map Size Code Restrictions User Defined Fleet MapsType I Programming Information Page One Year Limited Warranty Warrantor Uniden America Corporation UnidenPage Page Page UBZZ01322ZB