|
Sound-powered Telephone
A sound-powered telephone is a communication device that allows users to talk to each other with the use of a handset, similar to a conventional telephone, but without the use of external power. This technology has been used since at least 1944 for both routine and emergency communication on ships to allow communication between key locations on a vessel if power is unavailable. A sound-powered phone circuit can have two or more stations on the same circuit. The circuit is always live, thus a user begins speaking rather than dialing another station. Sound-powered telephones are not normally connected to a telephone exchange. Operation The microphone transducer converts sound pressure from a user's voice into an electric current, which is then converted back to sound by a transducer at the receiver nodes. The most significant distinction between ordinary telephones and sound-powered telephones is in the operation of the microphone. Since the microphones used in most telep ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HMNZS Te Kaha Sound-powered Telephone 20080702
His or Her Majesty's New Zealand Ship (HMNZS) is the ship prefix used to identify warships and shore facilities commissioned into the Royal New Zealand Navy (RNZN). It derives from "His Majesty's Ship" (HMS) used in the United Kingdom. The British monarch is also equally and separately the New Zealand head of state. Should the monarch be female, the designation also changes to "Her" rather than "His" Majesty. On 1 October 1941, King George VI fixed his signature to the approval for the Royal New Zealand Navy and from that date all ships officially received the designation. See also *His Majesty's Australian Ship *His Majesty's Canadian Ship *List of ships of the Royal New Zealand Navy Sortable list of commissioned vessels of the Royal New Zealand Navy from its formation on 1 October 1941 to the present. It does not include vessels of the New Zealand Division of the Royal Navy, New Zealand Division (1921–1941) or New Zealand ... Royal New Zealand Navy Ship prefixes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radio
Radio is the technology of communicating using radio waves. Radio waves are electromagnetic waves of frequency between 3 hertz (Hz) and 300 gigahertz (GHz). They are generated by an electronic device called a transmitter connected to an antenna which radiates the waves. They can be received by other antennas connected to a radio receiver; this is the fundamental principle of radio communication. In addition to communication, radio is used for radar, radio navigation, remote control, remote sensing, and other applications. In radio communication, used in radio and television broadcasting, cell phones, two-way radios, wireless networking, and satellite communication, among numerous other uses, radio waves are used to carry information across space from a transmitter to a receiver, by modulating the radio signal (impressing an information signal on the radio wave by varying some aspect of the wave) in the transmitter. In radar, used to locate and track ob ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Power Outage
A power outage, also called a blackout, a power failure, a power blackout, a power loss, a power cut, or a power out is the complete loss of the electrical power network supply to an end user. There are many causes of power failures in an electricity network. Examples of these causes include faults at power stations, damage to Electric power transmission, electric transmission lines, Electrical substation, substations or other parts of the electricity distribution, distribution system, a short circuit, Cascading failure#Cascading failure in power transmission, cascading failure, fuse (electrical), fuse or circuit breaker operation. Power failures are particularly critical at sites where the environment and public safety are at risk. Institutions such as hospitals, Sewage Treatment, sewage treatment plants, and mining, mines will usually have backup power sources such as emergency power system, standby generators, which will automatically start up when electrical power is lost ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
United States Coast Guard
The United States Coast Guard (USCG) is the maritime security, search and rescue, and Admiralty law, law enforcement military branch, service branch of the armed forces of the United States. It is one of the country's eight Uniformed services of the United States, uniformed services. The service is a maritime, military, multi-mission service unique among the United States military branches for having a maritime law enforcement mission with jurisdiction in both domestic and international waters and a Federal government of the United States, federal regulatory agency mission as part of its duties. It is the largest coast guard in the world, rivaling the capabilities and size of most Navy, navies. The U.S. Coast Guard protects the United States' borders and economic and security interests abroad; and defends its sovereignty by safeguarding sea lines of communication and commerce across U.S. territorial waters and its Exclusive economic zone, Exclusive Economic Zone. Due to ever-ex ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Combat Information Center
A combat information center (CIC) or action information centre (AIC) is a room in a warship or Airborne early warning and control, AWACS aircraft that functions as a tactical center and provides processed information for command and control of the near battlespace or area of operations. Within other military commands, rooms serving similar functions are known as command centers. Regardless of the vessel or command locus, each CIC organizes and processes information into a form more convenient and usable by the commander in authority. Each CIC funnels communications and data received over multiple channels, which is then organized, evaluated, weighted and arranged to provide ordered timely information flow to the battle command staff under the control of the CIC officer and his deputies. Overview CICs are widely depicted in film and television treatments, frequently with large maps, numerous computer consoles and radar and sonar repeater displays or consoles, as well as the alm ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lookout
A lookout or look-out is a person in charge of the observation of hazards. The term originally comes from a naval background, where lookouts would watch for other ships, land, and various dangers. The term has now passed into wider parlance. Naval application Lookouts have been traditionally placed in high on masts, in crow's nests and tops. The International Regulations for Preventing Collisions at Sea (1972) says in part: : Every vessel must at all times keep a proper look-out by sight (day shape or lights by eyes or visual aids), hearing (sound signal or Marine VHF radio) and all available means (e.g. Radar, ARPA, AIS, GMDSS...) in order to judge if risk of collision exists. Lookouts report anything they see and or hear. When reporting contacts, lookouts give information such as, bearing of the object, which way the object is headed, target angles and position angles and what the contact is. Lookouts should be thoroughly familiar with the various types of distress si ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
United States Navy
The United States Navy (USN) is the naval warfare, maritime military branch, service branch of the United States Department of Defense. It is the world's most powerful navy with the largest Displacement (ship), displacement, at 4.5 million tons in 2021. It has the world's largest aircraft carrier fleet, with List of aircraft carriers in service, eleven in service, one undergoing trials, two new carriers under construction, and six other carriers planned as of 2024. With 336,978 personnel on active duty and 101,583 in the Ready Reserve, the U.S. Navy is the third largest of the United States military service branches in terms of personnel. It has 299 deployable combat vessels and about 4,012 operational aircraft as of 18 July 2023. The U.S. Navy is one of six United States Armed Forces, armed forces of the United States and one of eight uniformed services of the United States. The United States Navy traces its origins to the Continental Navy, which was established during ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sound Powered Telephone
A sound-powered telephone is a communication device that allows users to talk to each other with the use of a handset, similar to a conventional telephone, but without the use of external power. This technology has been used since at least 1944 for both routine and emergency communication on ships to allow communication between key locations on a vessel if power is unavailable. A sound-powered phone circuit can have two or more stations on the same circuit. The circuit is always live, thus a user begins speaking rather than dialing another station. Sound-powered telephones are not normally connected to a telephone exchange. Operation The microphone transducer converts sound pressure from a user's voice into an electric current, which is then converted back to sound by a transducer at the receiver nodes. The most significant distinction between ordinary telephones and sound-powered telephones is in the operation of the microphone. Since the microphones used in most telep ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Telephone Magneto
A telephone magneto is a hand-cranked electrical generator that uses permanent magnets to produce alternating current from a rotating armature. In early telegraphy, magnetos were used to power instruments, while in telephony they were used to generate electrical current to drive electromechanical ringers in telephone sets and activate signals on operator consoles. Telegraphy Telegraphy pre-dated telephony and magnetos were used to drive some of the early printing telegraph instruments. Manual telegraphy with keys and reception by either a needle instrument or a syphon recorder could be powered by batteries. The later automatic and printing instruments, such as the Wheatstone ABC telegraph, required greater currents that could be delivered by a hand-cranked magneto. A hand-crank was used to rotate a belt drive that increases the rotational speed of an armature with a pair of coils between the poles of a stationary horseshoe magnet. Telephony Many early manual telephones h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Communication
Communication is commonly defined as the transmission of information. Its precise definition is disputed and there are disagreements about whether Intention, unintentional or failed transmissions are included and whether communication not only transmits semantics, meaning but also creates it. Models of communication are simplified overviews of its main components and their interactions. Many models include the idea that a source uses a code, coding system to express information in the form of a message. The message is sent through a Communication channel, channel to a receiver who has to decode it to understand it. The main field of inquiry investigating communication is called communication studies. A common way to classify communication is by whether information is exchanged between humans, members of other species, or non-living entities such as computers. For human communication, a central contrast is between Verbal communication, verbal and non-verbal communication. Verba ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Headphones
Headphones are a pair of small loudspeaker drivers worn on or around the head over a user's ears. They are electroacoustic transducers, which convert an electrical signal to a corresponding sound. Headphones let a single user listen to an audio source privately, in contrast to a loudspeaker, which emits sound into the open air for anyone nearby to hear. Headphones are also known as earphones or, colloquially, cans. Circumaural (around the ear) and supra-aural (over the ear) headphones use a band over the top of the head to hold the drivers in place. Another type, known as earbuds or earpieces, consists of individual units that plug into the user's ear canal; within that category have been developed cordless air buds using wireless technology. A third type are bone conduction headphones, which typically wrap around the back of the head and rest in front of the ear canal, leaving the ear canal open. In the context of telecommunication, a headset is a combination of a hea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
