What is the primary function of a transmitter?

The primary function of a transmitter is to convert electrical signals into radio frequency signals for broadcast. This process involves taking the electrical signals, which may carry audio or data information, and modulating them onto a carrier frequency that can be effectively transmitted over the airwaves.

In the context of radio communication, this modulation is crucial, as it allows the information to be sent over long distances and ensures it can be received by compatible receivers. By encoding audio, video, or data onto a radio frequency, the transmitter enables communication over various frequencies used in radio, television, and data links.

While other functions mentioned in the possible answers are important in the broader process of signal transmission and reception, they do not define the primary role of a transmitter. For example, capturing audio and video signals relates more to the role of microphones and cameras rather than transmitters. Amplifying weak signals is often a task for different components in the communication system, such as amplifiers or repeaters, rather than the transmitter itself. Filtering out unwanted frequencies is done by filters implemented in different parts of a communication system to ensure signal clarity but doesn't describe the fundamental function of converting and broadcasting signals which is central to a transmitter's operation.