Uniden BC296D manual Trunked Scanning

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operation. When a user transmits (on an input frequency), the signal is picked up by the repeater and retransmitted (on an output frequency). The user’s radios always listen for activity on the output frequency and transmit on the input frequency.

Since the repeater is located very high, there is a very large line of sight. Typical repeater systems provide coverage out to about a 25 mile radius from the repeater location.

Trunked Scanning

While conventional scanning worked great while there were only a few groups wanting to use the frequencies, with the advent of smaller, lower-cost radios more and more agencies and businesses wanted to take advantage of the utility of 2- way radio. As a result, the bands that were used most became full, so new users were not able to take advantage of the technology as quickly as they wanted.

Trunking solved this frequency shortage by allowing multiple groups to use the same set of frequencies in a very efficient way. While each type of trunking system operates a little differently (see the next few sections), they all work on the same basic premise: even in a system with a lot of users, only a few users are ever transmitting at any one time.

Instead of being assigned a frequency, as with conventional systems, each group is assigned a Talkgroup ID. A central computer controls the frequency each group operates on...and this frequency selection is made each time a user transmits. So, while on a conventional system queries, replies, and follow-ups are all on a single frequency, they could each be on completely different frequencies on a trunked system. This semi-random frequency assignment made monitoring such a system impossible prior to Uniden’s invention of the Trunktracking scanner.

Motorola Trunking

While there are 4 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 talkgroup information to the control channel. The computer then assigns that talkgroup to a specific voice channel and transmits that data over the control channel. All radios in that talkgroup 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 it is OK to start talking.

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Contents Page Page Contents Searching PC Control Mode Cloning Scanner Settings Page FCC Wants You To Know Scanning Legally Introduction Page Using this Manual Conventional Scanning Understanding ScanningSimplex Operation Repeater OperationTrunked Scanning Edacs Trunking Page LTR Trunking Understanding Banks and ChannelsGetting More Information Buttons and Controls Quick Look at Your ScannerIcon Description Display IconsIncluded With Your Scanner Installing the Battery Pack Setting Up Your ScannerCharging the Battery Pack Installing the Antenna Nickel-Metal Hydride Battery DisposalInstalling the Belt Clip Using Headphones or an External SpeakerListening Safely Basic Operation Setting the SquelchTurning On the Scanner Manually Selecting a Channel Using the MenuLocking/Unlocking Banks Scanning Programmed ChannelsLocking/Unlocking Channels Restoring All Locked Out ChannelsPriority Plus Scanning Priority ScanningListening to the Input Channel Dimmer Light Setting Using the BacklightDimmer Time Setting Controlling How Much Information AppearsLocking the Enter key Turning the Key Beep On/OffLocking the Keypad Disabling the APCO25 CardSetting Squelch Mode Turning Battery Save On/OffMuting All Audio Searching for Active Talkgroups ID Search Trunk Scanning OptionsScanning Only Stored Talkgroups ID Scan Monitoring Talkgroup ID’sLocking Out Talkgroups Holding on a Single TalkgroupEdacs Blockout Edacs Patch Tracking Unlocking All TalkgroupsSetting Data Skip Setting Chain SearchSearching Holding on an Active FrequencyStoring Found Frequencies Skipping FrequenciesAutomatically Storing Frequencies Setting Subaudible Tones for SearchingSearching for Subaudible Tones Setting a Search Range Setting Delay for All Search RangesAttenuating All Search Ranges Searching for Trunk Systems Service Search Skip Service SearchUsing Weather Alert Same Using Weather Search and Weather Alert SameSearching for a Weather Broadcast Dssccc Testing the Weather Alert Programming Bank Information Bank ConfigurationAssigning Bank Names Deleting Frequencies from Channels General ProgrammingTransferring Channel Information Entering Alpha InformationPage Select a Channel to Program Programming Conventional ChannelsEnter the Frequency Setting the Subaudible Tone Option Setting the DelayAssigning a Text Tag Setting the Attenuator Setting Beep AlertChanging the Frequency Step Setting the Modulation ModeSetting Priority Channels Programming Trunked Systems Using I-Call Motorola and Edacs only Setting Trunking DelayTurning I-Call On and Off for ID Search Multi-Track Setting Priority Talkgroups Motorola and Edacs onlyTurning I-Call On for ID Scan Multi-Track Operational Details Programming Motorola Systems Using Control Channel ProgrammingProgramming Type2/Digital VHF and UHF Systems Programming Type 2/Digital 800 and 900 MHz SystemsProgramming Type I and IIi Hybrid Systems Toggling the Status Bit Toggling End Code Detect Programming Edacs Channels Programming Edacs SystemsSetting Edacs Decimal Mode Setting Edacs Emergency AlertProgramming Apco Systems Setting Apco 25 Sound QualityPage Programming LTR Systems Storing Known Talkgroups Programming TalkgroupsStoring Found Talkgroups Press MENU/BACKAdding a Text Tag to an ID List Deleting Stored Talkgroup ID’sSeeing Talkgroup Activity PC Control Mode Using the Remote InterfaceCloning Scanner Settings Clone Care and Maintenance Troubleshooting Problem Suggestion Specifications Glossary of Terms Page Page Page Appendix Preset Fleet MapsPreset Map Block Type I Programming Information User Defined Fleet MapsFleet Map Size Codes NWR-SAME Event Code Reverse List 71.9 74.4 77.0 79.7 82.5 85.4 88.5 BC296D Flow Charts Scan Option Conventional System Option Dimmer Dimmer Light Dimmer Time Screen Mask Uniden America Corporation One Year Limited Warranty