United States Naval Sea Cadet Corps
Region 7-1 – Recruit Training
Ship’s Interior Communications
United States Naval Sea Cadet Corps
Region 7-1 – Recruit Training
Introduction
• Interior communications deal with those forms of communication between a sender and a receiver aboard the same ship.
• Interior communications are carried out via sound and some visual methods.
• Communications by messenger, probably the most ancient of all methods, remains the most reliable system.
United States Naval Sea Cadet Corps
Region 7-1 – Recruit Training
Class Objectives
1) Define the purpose of interior communications systems.
2) Identify all types of interior communications systems.
United States Naval Sea Cadet Corps
Region 7-1 – Recruit Training
Purpose of InteriorCommunication Systems
• Various stations within a ship must be able to communicate with one another. For example:– The ship’s DC parties must be able to communicate with the DCC
and bridge during an emergency
– The bow lookouts must be able to report to the OOD what they see and hear
– Primary flight control must be able to communicate with sailors moving aircraft on the flight deck
• The quicker a message moves through the ship’s interior the more efficient the ship will operate.
United States Naval Sea Cadet Corps
Region 7-1 – Recruit Training
Communications Equipment
• There are four basic types of interior communications equipment:– Voice Tube
– Ship’s Service Telephone
– Shipboard Announcing Systems
– Sound powered telephone system
United States Naval Sea Cadet Corps
Region 7-1 – Recruit Training
Voice Tube
• Primary means of interior communications on most mine craft and patrol boats.
• Requires neither electrical or sound power.
• On large ships it is only used for short distances.
United States Naval Sea Cadet Corps
Region 7-1 – Recruit Training
Ship’s Service Telephone
• Similar to a regular telephone system in your house.
• Can communicate with any part of the ship just by dialing a phone number.
• When the ship is alongside, the ship can be connected with the shore to allow outside calls.
• One disadvantage: the number of talkers it can reach at a time is small.
United States Naval Sea Cadet Corps
Region 7-1 – Recruit Training
Shipboard Announcing System
• In the old Navy an all hands order was passed by word of mouth by the Boatswain’s Mate.
• Now the BM’s can pass the word over the MC Circuit while others can stay where they are.
• The basic MC circuit is the 1MC over which word can be passed to every space in the ship.
United States Naval Sea Cadet Corps
Region 7-1 – Recruit Training
Shipboard Announcing System
• Transmitters for the 1MC are found on the bridge, quarterdeck, and central station.
• Except for emergency no call may be passed over the 1MC unless authorized by the OOD, Executive Officer, or the captain.
• Some parts of the ship have independent MC circuits such as engineering (2MC) and hanger deck (3MC)
United States Naval Sea Cadet Corps
Region 7-1 – Recruit Training
Shipboard Announcing System
• 1MC, 2 MC, 3MC, and 6 MC are all one-way means of communication.
• MC circuits such as the 21MC (Captain’s Command) provide two-way communications also known as squawk boxes.
United States Naval Sea Cadet Corps
Region 7-1 – Recruit Training
Shipboard Announcing System
CIRCUIT SYSTEM1MC General2MC Propulsion plant3MC Aviators4MC Damage control5MC Flight deck6MC Intership7MC Submarine control8MC Troop administration and control9MC Underwater troop communication18MC Bridge19MC Aviation Control
CIRCUIT SYSTEM21MC Captain’s command22MC Electronic control23MC Electrical control24MC Flag command26MC Machinery control27MC Sonar and radar control29MC Sonar control and information30MC Special weapons31MC Escape truck32MC Weapons control
Abbreviated MC Circuit List
United States Naval Sea Cadet Corps
Region 7-1 – Recruit Training
Sound Powered Telephones
• Phones that operate on voice power, no batteries or external electrical power source.
• The mouthpiece and earpieces can be used interchangeably; you can talk into an earpiece and hear through the mouthpiece!
• Sound powered telephone talkers are found in the lookouts, the bridge, in CIC, and enginerooms to name a few.
United States Naval Sea Cadet Corps
Region 7-1 – Recruit Training
Sound Powered Telephones
• Typical sound powered headset consists of a headband, earpiece, breastplate, and a yoke that holds the mouthpiece.
• The headset has a wire which may be up to 50 feet long.
• Sound powered headsets plug into special telephone jacks.
• Never secure the headset until you have permission to do so.
headband
earpiece
breastplate
mouthpiece
United States Naval Sea Cadet Corps
Region 7-1 – Recruit Training
Summary
1) Define the purpose, use, and characteristics of interior communications systems.
2) Identify all types of interior communications systems.
United States Naval Sea Cadet Corps
Region 7-1 – Recruit Training
Questions???