1 Main Circuit

Shipboard public address circuits used by the United States Navy Then-Rear Admiral (lower half) Michelle J. Howard addresses the crew of USS Wasp (LHD-1). General quarters A call to general quarters aboard a United States Navy vessel Problems playing this file? See media help. 1 Main Circuit (1MC) is the shipboard public address circuits on United States Navy and United States Coast Guard vessels. This provides a means of transmitting general information and orders to all internal ship spaces and topside areas, and is loud enough that all embarked personnel are (normally) able to hear it. It is used to put out general information to the ship's crew on a regular basis each day. The system consists of an amplifier-oscillator group which is located in the IC/gyro room, a microphone control station, portable microphones at each control station and loudspeakers located throughout the ship. Control stations for the 1MC announcing system are located at the pilot house, OOD stations on the quarterdecks, aft steering and Damage Control Central area. During an incident involving a casualty, the 1MC is a communication tool used by DCAs (damage control assistants) to keep ship members alerted