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 installations, beginning 1 February 1904 "the call to be given by ships in distress or in any way requiring assistance shall be 'C Q D' ".[1]
Background
Land telegraphs had adopted the convention of using "CQ" ("sécu", from the French word sécurité)[2] to identify alert, or precautionary messages of interest to all stations along a telegraph line. CQ had then been adopted in maritime radiotelegraphy as a "general call" to any ship or land station.
In landline use there was no general emergency signal, so the Marconi company added a "D" ("distress") to CQ in order to create a distress call. Sending "D" was already used internationally to indicate an urgent message. Thus, "CQD" was understood by wireless operators to mean All stations: Distress.[a] Although used worldwide by Marconi operators, CQD was never adopted as an international standard, since it can easily be mistaken for a mere general call "CQ" when reception is poor.
CQD supplanted by SOS
At the first International Radiotelegraphic Convention, held in Berlin in 1906, Germany's Notzeichen distress signal of three-dots three-dashes three-dots ( ▄ ▄ ▄ ▄▄▄ ▄▄▄ ▄▄▄ ▄ ▄ ▄ ) was adopted as the international Morse code distress signal.[4]
This distress signal soon became known as "SOS" because it has the same dash-dot sequence as the letters S O S with the gaps between the letters removed, and in fact it is properly written SOS, with an overbar, to distinguish it from the three individual letters. In contrast, CQD is transmitted as three distinct letters with a short gap between each, like regular text. The SOS distress code is also easier to hear as it is 9 symbols long, while no other character or sign is longer than 6 symbols. Germany had first adopted this distress signal in regulations effective 1 April 1905.)[5][6]
History of wireless distress rescues
From 1899–1908, nine documented rescues were made by the use of wireless. The earliest of these was a distress call from the East Goodwin lightship. However, for the earliest of these, there was no standardized distress signal. The first US ship to send a wireless distress call in 1905 simply sent HELP (in both International Morse and American Morse).[3]: 218
By February 1904, the Marconi Wireless Company required all its operators to use CQD for a ship in distress or for requiring URGENT assistance.[1] In the early morning of 23 January 1909, whilst sailing into New York from Liverpool, RMS Republic collided with the Italian liner SS Florida in fog off the island of Nantucket, Massachusetts, United States. Radio Operator Jack Binns sent the CQD distress signal by wireless transmission.[7][8]
On 15 April 1912, RMS Titanic radio operator Jack Phillips initially sent "CQD", which was still commonly used by British ships. Harold Bride, the junior radio operator, suggested using SOS, saying half-jokingly that it might be his last chance to use the new code. Phillips thereafter began to alternate between the two.[3]: 1911 Although Bride survived, Phillips perished in the sinking.[9]
See also
- 500 kHz (Morse distress frequency)
- 2182 kHz (voice distress frequency)
- Distress signal
- Global Maritime Distress Safety System
- Mayday
- Prosigns for Morse code
- SOS
Footnotes
- ^ Contrary to popular belief, CQD does not stand for "Come Quick, Danger", "Come Quickly: Distress", "Come Quick – Drowning!", or "C Q Danger" ("Seek You, Danger"); these are backronyms.[3]: 218
References
- ^ a b Turnbull, G.E. (1913). "Distress Signalling". The Year-book of Wireless Telegraphy and Telephony. pp. 318–322.
- ^ Dictionnaire français-anglais, anglais-français. Paris, FR: Dictionnaires Le Robert-VUEF. 2002.
re: sécurité: e.g. des mesures de sécurité, "safety measures, precautions, or alerts"
- ^ a b c Campbell, Ballard C. (2008). Disasters, Accidents, and Crises in American History. Infobase Publishing. ISBN 1438130120.
- ^ "Service Regulation XVI". 1906 International Wireless Telegraph Convention. U.S. Government Printing Office. p. 38.
- ^ "Regelung der Funkentelegraphie im Deutschen Reich". Elektrotechnische Zeitschrift: 413–414. 27 April 1905.
- ^ "German Regulations for the Control of Spark Telegraphy". The Electrician: 94–95. 5 May 1905.
- ^ Caddell, Alfred M. (April 1924). "C Q D". Radio Broadcast. pp. 449–455.
- ^ "Jack Binns: Hero". JackBinns.org.
- ^ "Thrilling story by Titanic's surviving wireless man". 19 April 1912. Retrieved 29 September 2018.
Bibliography
- Stephan Dubreuil, Come Quick, Danger: A history of marine radio in Canada, Ottawa: Fisheries and Oceans Canada, Coast Guard, 1998. OCLC 39748172.
- Pete Caesar, SOS ... CQD: Four Ships in Trouble, Muskegon, Mich.: Marine Press, 1977. OCLC 3182026.