How Does a Four Wire Intercom System Work?

Four-wire intercom systems can be configured for use in a residential setting or in commercial applications, including connections between television studios. In their simplest forms intercoms act as analog systems, while the majority of four-wire systems used in the 21st century are digital.

Wires

Four-wire intercom systems use a pair of copper wires to create each single wire within the intercom system. The microphone and speaker base for each end of the intercom system carries audio -- and in some cases video -- through the copper wires to a second or multiple base station.

Development

Four-wire intercom systems were developed and commonly used in Western European telecommunication systems throughout the 1980s. These systems allowed telecommunications between cities throughout Western Europe.

Satellite

In the 21st century, four-wire intercom systems generally use digital technology to pass audio and video between base stations. They can also use satellites to bounce information between base stations.

References

• Intercoms Online: Wired Intercoms
• Smarthome: Room Station with Remote Scan for 4 Wire Intercom/Sound System
• Broadcast Engineering: Intercom Systems