If you want to monitor the area around a Substation, you simply press the button on the Master that corresponds to the Substation you want to monitor. You will then hear everything happening around the Substation, but they will not hear you unless you press the Talk button first. To stop monitoring you simply press the Off button. While the Master is in monitor mode, other Substations cannot audibly call the Master, but an LED lights above the corresponding Substation switch on the Master for a period of 20 seconds.
Each Substation can call the Master by pressing the Call button. A tone will sound as long as the Call button is pressed. Once the Master responds by pressing the Talk button, the Substation can then talk hands free and the Master station operator will need to press the Talk button to reply.
The Master calls a Substation by pressing the corresponding Substation button and then pressing the Call button to sound a ring tone. The Master does not have to wait for a reply and can simply press the Talk button to speak.
Substations cannot communicate with each other with this system, but master stations can as long as there is 12 conductor wiring between master stations.
Receiving a call from another master: