Which device works as transmitter and receiver pairs to facilitate digital signal transmission over long distances?

The choice of extenders is correct because they are specifically designed to transmit and receive signals over long distances while maintaining digital signal integrity. In audio-visual setups, extenders can be used to extend the reach of signals beyond standard cable limitations, which is crucial in scenarios where the source and display are located far apart.

Extenders typically utilize various technologies such as HDMI over Ethernet or fiber optics to cover greater distances without significant loss of quality. This characteristic makes them ideal for professional AV installations where the quality of the signal is essential, and the distance between devices often exceeds the limitations of standard cables.

Other devices like switches, amplifiers, and receivers serve different functions within an AV system. Switches route signals between multiple sources and displays but do not extend distances. Amplifiers boost signal strength but are not designed for transmission, and receivers decode signals from sources but do not function as transmitters. Thus, extenders uniquely combine the transmitting and receiving functions necessary for successful long-distance digital signal transmission.