What does the PTT button do on a two-way radio?

The PTT button, which stands for "Push-To-Talk," is specifically designed to enable the user to transmit their voice over the two-way radio. When you press the PTT button, it activates the radio's transmitter, allowing your voice to be sent over the airwaves to communicate with others on the same frequency. This functionality is essential for effective communication in firefighting operations and ensures that important information can be conveyed quickly and clearly.

In this context, the other options do not pertain to the primary function of the PTT button. Increasing the volume pertains to audio output control, changing the frequency relates to tuning the radio to different channels, and turning the radio on is a power-related function. None of these actions involve the operation of transmitting a message, which is the core purpose of the PTT button.