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 in “Preset Fleet Maps” on Page 123. 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.

Motorola ASTRO 25 (APCO 25) – these radios are similar to Type II systems, but send only the radio ID and radio channel code to the control channel, trans- mitting voice in digital form.

23

Understanding Scanning

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Uniden UBCD396T owner manual Systems in use are

UBCD396T specifications

The Uniden UBCD396T is a highly versatile and compact digital scanner that has gained a reputation among enthusiasts and professionals alike for its impressive features and capabilities. Designed primarily for public safety scanning, this portable scanner allows users to stay informed about local emergency services, including police, fire, and medical operations.

One of the key features of the UBCD396T is its ability to receive a wide range of frequencies. It covers VHF, UHF, and 700/800 MHz bands, which are commonly used by various agencies. With support for both analog and digital modes, users can enjoy clear audio and access to multiple communication protocols.

The scanner is equipped with Uniden's advanced APCO-25 digital decoding technology, enabling it to receive and accurately decode P25 digital signals. This is particularly beneficial for users in areas where digital trunking systems are in use, ensuring they can access critical communications without the hassle of missing important information.

A standout characteristic of the UBCD396T is its Dynamic Memory Management system, which allows users to create and manage multiple scanning banks efficiently. With 1000 channels and the ability to store additional frequencies, users can customize their scanning experience based on their preferences and needs. The scanner also supports GPS connectivity, enabling location-based scanning that automatically alters the frequency range based on the user's position.

Another notable feature is the scanner's customizable display and backlight options. Users can adjust the brightness and color settings to suit their preferences, making it easy to operate even in low-light conditions. The UBCD396T also boasts a built-in rechargeable battery, providing hours of continuous operation, ideal for users on the go.

Furthermore, the UBCD396T includes features such as a dedicated search mode, allowing users to scan unprogrammed frequencies, and a close call function that detects nearby transmissions instantly. The USB connectivity enables easy software updates, ensuring users can keep their devices up to date with the latest technologies.

In summary, the Uniden UBCD396T is a powerful and flexible digital scanner that offers a suite of features suited for both casual users and serious enthusiasts. Its ability to decode various communication types, along with user-friendly customization options, makes it a standout choice for anyone looking to stay connected to the world around them.