CQ is a code used by
wireless
Wireless communication (or just wireless, when the context allows) is the transfer of information between two or more points without the use of an electrical conductor, optical fiber or other continuous guided medium for the transfer. The most ...
operators, particularly those communicating in
Morse code
Morse code is a method used in telecommunication to encode text characters as standardized sequences of two different signal durations, called ''dots'' and ''dashes'', or ''dits'' and ''dahs''. Morse code is named after Samuel Morse, one of ...
, (), but also by voice operators, to make a general call (called a ''CQ call''). Transmitting the letters ''CQ'' on a particular
radio
Radio is the technology of signaling and communicating using radio waves. Radio waves are electromagnetic waves of frequency between 30 hertz (Hz) and 300 gigahertz (GHz). They are generated by an electronic device called a transmit ...
frequency
Frequency is the number of occurrences of a repeating event per unit of time. It is also occasionally referred to as ''temporal frequency'' for clarity, and is distinct from ''angular frequency''. Frequency is measured in hertz (Hz) which is eq ...
is an invitation for any operators listening on that frequency to respond. It is still widely used in
amateur radio
Amateur radio, also known as ham radio, is the use of the radio frequency spectrum for purposes of non-commercial exchange of messages, wireless experimentation, self-training, private recreation, radiosport, contesting, and emergency communic ...
.
History and usage
The CQ call was
originally used by landline telegraphy operators in the
United Kingdom
The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom (UK) or Britain, is a country in Europe, off the north-western coast of the continental mainland. It comprises England, Scotland, Wales and North ...
. French was, and still is, the official language for international postal services, and the word
sécurité
Sécurité (; French: ''sécurité'') (often repeated thrice, "Sécurité, sécurité, sécurité") is a procedure word used in the maritime radio service that warns the crew that the following message is important safety information. The most co ...
was used to mean "safety" or "pay attention". It is still used in this sense in international telecommunications.
The letters CQ, when pronounced in French, resemble the first two syllables of ', and were therefore used as shorthand for the word. It sounds also like the French "c'est qui?", which means "who's there?". In English-speaking countries, the origin of the abbreviation was popularly changed to the phrase "seek you" or, later, when used in the
CQD
CQD (transmitted in Morse code as ) is one of the first distress signals adopted for radio use. On 7 January 1904 the Marconi International Marine Communication Company issued "Circular 57", which specified that, for the company's ins ...
distress call, "Calling all distress".
CQ was adopted by the
Marconi Company
The Marconi Company was a British telecommunications and engineering company that did business under that name from 1963 to 1987. Its roots were in the Wireless Telegraph & Signal Company founded by Italian inventor Guglielmo Marconi in 1897 ...
in 1904 for use in
wireless telegraphy
Wireless telegraphy or radiotelegraphy is transmission of text messages by radio waves, analogous to electrical telegraphy using cables. Before about 1910, the term ''wireless telegraphy'' was also used for other experimental technologies for ...
by
spark-gap transmitter
A spark-gap transmitter is an obsolete type of radio transmitter which generates radio waves by means of an electric spark."Radio Transmitters, Early" in Spark-gap transmitters were the first type of radio transmitter, and were the main type use ...
, and was adopted internationally at the 1912 London International Radiotelegraph Convention, and is still used.
A variant of the CQ call, ''
CQD
CQD (transmitted in Morse code as ) is one of the first distress signals adopted for radio use. On 7 January 1904 the Marconi International Marine Communication Company issued "Circular 57", which specified that, for the company's ins ...
'', was the first code used as a
distress signal
A distress signal, also known as a distress call, is an internationally recognized means for obtaining help. Distress signals are communicated by transmitting radio signals, displaying a visually observable item or illumination, or making a soun ...
. It was proposed by the
Marconi Company
The Marconi Company was a British telecommunications and engineering company that did business under that name from 1963 to 1987. Its roots were in the Wireless Telegraph & Signal Company founded by Italian inventor Guglielmo Marconi in 1897 ...
and adopted in 1904, but was replaced between 1906 and 1908 by the
SOS code. When the ''
Titanic
RMS ''Titanic'' was a British passenger liner, operated by the White Star Line, which sank in the North Atlantic Ocean on 15 April 1912 after striking an iceberg during her maiden voyage from Southampton, England, to New York City, United ...
'' sank in 1912, it initially transmitted the distress call "''CQD DE MGY" (with "''MGY" being the ship's call sign). ''Titanics radio operator subsequently alternated between SOS and CQD calls afterwards.
In
amateur radio
Amateur radio, also known as ham radio, is the use of the radio frequency spectrum for purposes of non-commercial exchange of messages, wireless experimentation, self-training, private recreation, radiosport, contesting, and emergency communic ...
usage, a CQ call can be qualified by appending more letters, as in ''CQ DX'' (meaning "calling all stations located in a different continent to the caller"), or the
ITU
The International Telecommunication Union is a specialized agency of the United Nations responsible for many matters related to information and communication technologies. It was established on 17 May 1865 as the International Telegraph Unio ...
call sign
In broadcasting and radio communications, a call sign (also known as a call name or call letters—and historically as a call signal—or abbreviated as a call) is a unique identifier for a transmitter station. A call sign can be formally assigne ...
prefix for a particular country (e.g. ''CQ VK'' for "calling
Australia
Australia, officially the Commonwealth of Australia, is a Sovereign state, sovereign country comprising the mainland of the Australia (continent), Australian continent, the island of Tasmania, and numerous List of islands of Australia, sma ...
"). The originator of the call can be identified by appending the letters ''DE'' (
French for "from", also means "this is...") and the call sign of the transmitting station.
In the use of
single-sideband (SSB) voice or
CW mode (
morse code telegraphy), an
amateur radio
Amateur radio, also known as ham radio, is the use of the radio frequency spectrum for purposes of non-commercial exchange of messages, wireless experimentation, self-training, private recreation, radiosport, contesting, and emergency communic ...
operator often makes a general call by transmitting CQ repeatedly (such as "CQ CQ CQ") so that other operators scanning for such calls are aided by the familiar rhythmic sound in quickly discriminating distant (weak signal) general callers from other traffic and
spurious emission
In radio communication, a spurious emission is any component of a radiated radio frequency signal the complete suppression of which would not impair the integrity of the modulation type or the information being transmitted. A radiated signal out ...
s. This technique allows the other operators to zero-in as close to the caller's center frequency using the human ear to fine-tune their transceiver before engaging the caller in a two-way communication.
The use of a CQ call is almost always used in
single-sideband (SSB) voice or
CW mode (
morse code telegraphy). Unlike
FM mode, in the SSB voice and CW mode areas of the amateur radio bands operators are free to center their transmissions where it is most optimal (such as away from adjacent traffic that can interfere) and not expected to use whole-number, divisible-by-five, or otherwise channelized center frequencies. CQ is constantly used on the HF shortwave amateur bands but very rarely used in the FM voice mode of transmission or on FM repeaters common on the VHF and UHF local bands since tuning of a repeater or FM signal does not require the aid of human perception to perfectly tune the signal.
The code was used as part of the chorus to the song "Communications" by
Slim Gaillard.
See also
*
Amateur radio
Amateur radio, also known as ham radio, is the use of the radio frequency spectrum for purposes of non-commercial exchange of messages, wireless experimentation, self-training, private recreation, radiosport, contesting, and emergency communic ...
* ''
CQ Amateur Radio
''CQ Amateur Radio'' (also known simply as ''CQ'' or ''CQ magazine'', and formerly as ''CQ: The Radio Amateur's Journal'') is a magazine for amateur radio enthusiasts first published in 1945. The English language edition is read worldwide; Spani ...
'', English-language magazine
* ''
CQ ham radio
''CQ ham radio'' is a monthly amateur radio enthusiast magazine published in Japan. The magazine is published in Japanese and draws its subscription base primarily from Japan. The name of the magazine is derived from the international amate ...
'', Japanese-language magazine
*
Q code
The Q-code is a standardised collection of three-letter codes that each start with the letter "Q". It is an operating signal initially developed for commercial radiotelegraph communication and later adopted by other radio services, especially ...
s
*
Universal Postal Union
The Universal Postal Union (UPU, french: link=no, Union postale universelle), established by the Treaty of Bern of 1874, is a specialized agency of the United Nations (UN) that coordinates postal policies among member nations, in addition to t ...
References
General references
*
*
*
* {{cite book , title=Commercial Traffic Regulations, 1915 , publisher=United States Naval Radio Service , location=Government Printing Office, Washington, DC
Amateur radio
Morse code
Radio communications
Operating signals