Which radio system requires the user to manually select the channel to communicate?

The correct answer is based on the operational characteristics of conventional radio systems. In a conventional radio system, each channel is distinct, and the user must manually select the specific channel they wish to use for communication. This means that if a firefighter wants to communicate on a certain frequency or with a particular group, they must turn the dial or select that channel themselves on their radio.

Conventional systems are straightforward and often used for direct communication needs, such as among fire stations, where clear and direct lines of communication are necessary. This system relies on predetermined frequency assignments, and each channel corresponds to a specific group or type of communication.

In contrast, trunked radio systems automatically manage channel assignments, which allow users to communicate without needing to change channels manually. Multiplex systems involve sending multiple signals over a single channel, and repeaters are used to extend the coverage of radio signals rather than selecting channels.