Uniden UBC396T specifications Types of Trunking Systems, Motorola Trunking

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 TrunkTracker scanner.

Not only does your BCD396T scan channels like a conventional scanner, it actually follows the users of a trunked radio system. Once you know a talk group’s ID, you won’t miss any of the action.

If you are a new scanner enthusiast, you might want to read the first part of this manual and use your scanner in conventional mode before you begin trunk tracking. Understanding scanning fundamentals and terminology will make trunk tracking much easier. If you are already an experienced scanner operator, you might want to go to “Programming Motorola Systems” on Page 63, “Programming EDACS Systems” on Page 67, or “Programming LTR Systems” on Page 70 now.

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 (or as many as 4 per system but only one is active at any one time), plus one or more voice channels (typically 10, 20, or 28 total channels). When a user presses Push To Talk (PTT) to transmit, their radio first sends their talk group information to the control channel.

Understanding Scanning

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