An intercom is a voice system independent of the telephone. It is closed circuit and is generally used to facilitate communication within a limited area such as a building. Intercoms are commonly used in offices, homes, commercial buildings and residential buildings. The primary functions of intercoms are to provide security and facilitate communication. The parts of an intercom system include:
Intercom Base Station
The base station is the central component to an intercom system and is the point from which the entire system is controlled. All other parts of the intercom – such as desk stations or wall mounts – are connected to the main base station. Because it is connected to all intercom stations, the main base station possesses the ability to broadcast messages to all stations at once and therefore may act as a public address system. The main base station has the capability to initiate intercom communication with any station connected to the system and also has the capability to mute any station. Base stations are also referred to as “master stations”.
Substations are what would commonly be known as intercom speakers. Substations broadcast one-way communication from the base station and do not have buttons or microphones – they are not capable of initiating correspondence, they are merely speakers in an intercom system. Substations are commonly used in factories, airports, schools, train stations, film sets, and malls. There are smaller uses for substations as well, such as in the case of some baby monitors where a base station monitor is placed in a room with a baby and a substation monitor is taken along with the parent. The parent can hear the baby, but the baby cannot hear the parent.
Intercom stations are the parts of an intercom that connect to the bas station, such as desk modules, headsets, handsets, and wall mounted intercom stations. Intercom stations possess a talk button and microphone and may initiate communication with the base station. Intercom stations are actually referred to as substations with additional functionality, thus being the ability to engage in two-way communication.
An intercom station generally has several parts that it is comprised of. Most importantly, it will have a panel with switches including a “talk” button. Using the talk button turns on the microphone function within the speaker, allowing the individual using the intercom to relay his or her vocal message. Often, the “talk” button must be pressed the entire time that the individual is speaking. When the “talk” button is activated, the speaker is being utilized as a microphone and therefore the intercom station can receive no sound. Further, each intercom station possess a power source and wiring which connects it to the base station.