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.
~4 min read
Article
7 sectionsContents
- Background
- Replacement
- History of wireless distress rescues
- See also
- Footnotes
- References
- Bibliography
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.
==Background== Landline and submarine telegraphers' telegraphs had adopted the convention of using the station code "CQ" to all stations along a telegraph line. As the first wireless operators were taken from the already trained landline telegraphers, the current practices carried forward and CQ had then been adopted in maritime radiotelegraphy as a "general call" to any ship or land station.