Which device interfaces a telephone line to the station's audio mixing console for the purpose of putting callers on the air?

A telephone hybrid is specifically designed to interface telephone lines with audio mixing consoles in a broadcasting setting. Its primary function is to handle the audio signals from callers, allowing them to be mixed with other audio sources for broadcast. The telephone hybrid converts the audio from the telephone line into a format suitable for the mixing console, ensuring that the caller's voice is clear and that it can be seamlessly integrated into the on-air audio feed.

The technology in a telephone hybrid also includes echo cancellation, which prevents the caller from hearing their own voice as a delay, thus improving the quality of the conversation. This is crucial for live broadcasts, where clarity and real-time communication are essential.

While an audio interface can connect various audio sources to a digital audio workstation or computer, it is not specialized for telephone calls. A mixing desk is a broader term referring to the equipment used for combining various audio inputs but does not inherently connect to telephone lines. A digital audio workstation is software often used for recording and mixing audio, but it similarly lacks the specific functionality required to manage phone calls in a broadcast context.

In short, the telephone hybrid serves a unique and critical role in radio broadcasting by facilitating the connection and quality of audio from telephone callers.