DIP switches at the base of the call station select
different microphone gain levels, the call station ID,
and the speech filter. A service accessible rotary
control provides microphone level attenuation. LEDs
on the call station show which zones have been
selected. Three additional LEDs give visible feedback
on the active state of the microphone and the system.
Green flashing means standby (chime is sounding).
Green indicates microphone active. Amber indicates
that the system has detected a fault, and red indicates
that the system is in the emergency state.