Television also uses radio signals to send pictures and sound.

To send or receive sound through the conduit, the microphone or transmitter must be positioned within the waveguide.

In 1927 AT&T had demonstrated a system that sent television images and sound over telephone lines.

Many fans and regular callers of the show have home-brewed their own electronic devices to aid in sending sound over the phone.

It was designed to send music and sound from the stage into the audience.

After that, Bell continued his experiments in communication, which led to the invention of the photophone - which sent sound on a beam of light.

The digital technology may someday be capable of sending images as well as sound for movies and television commercials.

The helmet sent stereo pictures and sound.

Physically centering the group sent sound up to high ceilings and distributed it equally.

It incorporated a high-frequency horn that sent sound through the middle of a 15-inch woofer for near-point-source performance.