The International Radiotelephony Spelling Alphabet or simply Radiotelephony Spelling Alphabet, commonly known as the NATO phonetic alphabet, is the most widely used set of clear-code words for communicating the letters of the Roman alphabet. Technically a radiotelephonic spelling alphabet, it goes by various names, including NATO spelling alphabet, ICAO phonetic alphabet and ICAO spelling alphabet. The ITU phonetic alphabet and figure code is a rarely used variant that differs in the code words for digits.
A radiotelephone, abbreviated RT, is a radio communication system for conducting a conversation; radiotelephony means telephony by radio. It is in contrast to radiotelegraphy, which is radio transmission of telegrams (messages), or television, transmission of moving pictures and sound. The term is related to radio broadcasting, which transmit audio one way to listeners. Radiotelephony refers specifically to two-way radio systems for bidirectional person-to-person voice communication between separated users, such as CB radio or marine radio. In spite of the name, radiotelephony systems are not necessarily connected to or have anything to do with the telephone network, and in some radio services, including GMRS, interconnection is prohibited.
The APCO phonetic alphabet, a.k.a. LAPD radio alphabet, is the term for an old competing spelling alphabet to the ICAO radiotelephony alphabet, defined by the Association of Public-Safety Communications Officials-International from 1941 to 1974, that is used by the Los Angeles Police Department (LAPD) and other local and state law enforcement agencies across the state of California and elsewhere in the United States. It is the "over the air" communication used for properly understanding a broadcast of letters in the form of easily understood words. Despite often being called a "phonetic alphabet", it is not a phonetic alphabet for transcribing phonetics.
The radiotelephony message PAN-PAN is the international standard urgency signal that someone aboard a boat, ship, aircraft, or other vehicle uses to declare that they need help and that the situation is urgent, but for the time being, does not pose an immediate danger to anyone's life or to the vessel itself. This is referred to as a state of "urgency". This is distinct from a mayday call, which means that there is imminent danger to life or to the continued viability of the vessel itself. Radioing "pan-pan" informs potential rescuers that an urgent problem exists, whereas "mayday" calls on them to drop all other activities and immediately begin a rescue.
A signal strength and readability report is a standardized format for reporting the strength of the radio signal and the readability (quality) of the radiotelephone (voice) or radiotelegraph signal transmitted by another station as received at the reporting station's location and by their radio station equipment. These report formats are usually designed for only one communications mode or the other, although a few are used for both telegraph and voice communications. All but one of these signal report formats involve the transmission of numbers.
Radiotelephony procedure includes various techniques used to clarify, simplify and standardize spoken communications over two-way radios, in use by the armed forces, in civil aviation, police and fire dispatching systems, citizens' band radio (CB), and amateur radio.
In current military use, combined operations are operations conducted by forces of two or more allied nations acting together for the accomplishment of a common strategy, a strategic and operational and sometimes tactical cooperation. Interaction between units and formations of the land, naval and air forces, or the cooperation between military and civilian authorities in peacekeeping or disaster relief operations is known as joint operations or interoperability capability.
The International Code of Signals (INTERCO) is an international system of signals and codes for use by vessels to communicate important messages regarding safety of navigation and related matters. Signals can be sent by flaghoist, signal lamp ("blinker"), flag semaphore, radiotelegraphy, and radiotelephony. The International Code is the most recent evolution of a wide variety of maritime flag signalling systems.
In broadcasting and radio communications, a call sign is a unique identifier for a transmitter station. A call sign can be formally assigned by a government agency, informally adopted by individuals or organizations, or even cryptographically encoded to disguise a station's identity.
The Combined Communications-Electronics Board (CCEB) is a five-nation joint military communications-electronics (C-E) organisation whose mission is the coordination of any military C-E matter that is referred to it by a member nation. The member nations of the CCEB are Australia, Canada, New Zealand, the United Kingdom, and the United States. The CCEB is the Sponsoring Authority for all Allied Communications Publications (ACPs). ACPs are raised and issued under common agreement between the member nations. The CCEB Board consists of a senior Command, Control, Communications and Computer (C4) representative from each of the member nations.
A Radio code is any code that is commonly used over a telecommunication system such as Morse code, brevity codes and procedure words.
A spelling alphabet is a set of words used to represent the letters of an alphabet in oral communication, especially over a two-way radio or telephone. The words chosen to represent the letters sound sufficiently different from each other to clearly differentiate them. This avoids any confusion that could easily otherwise result from the names of letters that sound similar, except for some small difference easily missed or easily degraded by the imperfect sound quality of the apparatus. For example, in the Latin alphabet, the letters B, P, and D sound similar and could easily be confused, but the words "bravo", "papa" and "delta" sound completely different, making confusion unlikely.
A radiogram is a formal written message transmitted by radio. Also known as a radio telegram or radio telegraphic message, radiograms use a standardized message format, form and radiotelephone and/or radiotelegraph transmission procedures. These procedures typically provide a means of transmitting the content of the messages without including the names of the various headers and message sections, so as to minimize the time needed to transmit messages over limited and/or congested radio channels. Various formats have been used historically by maritime radio services, military organizations, and Amateur Radio organizations.
Procedure words are words or phrases limited to radio telephone procedure used to facilitate communication by conveying information in a condensed standard verbal format. Prowords are voice versions of the much older procedural signs for Morse code which were first developed in the 1860s for Morse telegraphy, and their meaning is identical.
A plain-language radio check is the means of requesting and giving a signal strength and readability report for radiotelephony (voice) communications, and is the direct equivalent to the QSA and QRK code used to give the same report in radiotelegraph communications. SINPEMFO code is the voice signal reporting format developed by the ITU in 1959, but sees little use outside of shortwave listeners.
16-line message format, or Basic Message Format, is the standard military radiogram format for the manner in which a paper message form is transcribed through voice, Morse code, or TTY transmission formats. The overall structure of the message has three parts: HEADING, TEXT, and ENDING. This heading is further divided into procedure, preamble, address, and prefix. Each format line contains pre-defined content. An actual message may have fewer than 16 actual lines, or far more than 16, because some lines are skipped in some delivery methods, and a long message may have a TEXT portion that is longer than 16 lines by itself.
The QSA code and QRK code are interrelated and complementary signal reporting codes for use in wireless telegraphy. An enhanced format, SINPO code, was published in the ITU Radio Regulations, Geneva, 1959, but is longer and unwieldy for use in the fast pace of Morse code communications.
Allied Communication Procedures is the set of manuals and supplements published by the Combined Communications Electronics Board that prescribe the methods and standards to be used while conducting visual, audible, radiotelegraph, and radiotelephone communications within NATO member nations. These procedures relate to procedure words, radiotelephony procedure, Allied Military phonetic spelling alphabets, plain language radio checks, the 16-line message format (radiogram), and others.
Allied Communications Publications are documents developed by the Combined Communications-Electronics Board and NATO, which define the procedures for communicating in computer messaging, radiotelephony, radiotelegraph, radioteletype (RATT), air-to-ground signalling, and other forms of communications used by the armed forces of the five CCEB member countries and/or NATO.
