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Rescue at Sea | Article

Wireless Signals


The distress signal CQD originated from the signal CQ, expressing "seeking you," or "all stations." The signal CQ was commonly used among wireless operators -- and land-based telegraphers before them -- as a time-saving means of addressing all stations from one signal. The ability of CQ to convey distress was eventually diminished by frequent use. Therefore, in 1904 Guglielmo Marconi's wireless company announced the distress signal CQD would be used, signifying "Seeking you. Distress!" Or, "All stations. Distress!" 

However, while British wireless operators favored the CQD as their distress signal, the signal was not used universally. The Germans used SOE. The Americans used NC, which meant "call for help without delay." Each of these signals was sent as a sequence of distinct letters, with brief spaces in between. In an effort to achieve a faster and more attention-grabbing signal, delegates at the second International Radio Telegraphic Conference, held in Berlin in 1906, suggested a simpler signal -- SOS, which would be sent as a continuous stream,...---..., instead of a sequence of letters. By 1908 this proposal was ratified by all conference members except the United States. 

Although the U.S. lagged in adopting the new signal, the first SOS was transmitted from the American vessel "Arapahoe" in 1909, after a propeller shaft snapped. But CQD remained popular-primarily with the British. Wireless operator Jack Binns used CQD signals to save the sinking "Republic" in 1909. In 1912 the wireless operators aboard the "Titanic," Harold Bride and Jack Phillips, called for help using both SOS and CQD distress signals. 

After the sinking of the "Titanic," the United States officially adopted the SOS as its distress signal. The use of SOS soon became universal, and the standard signal ruled the high seas until early 1999. Then, in an agreement engineered by the United Nations, Morse Code itself was officially retired as a method of marine communication. Its replacement, the Global Maritime Distress and Safety System, relies on a system of satellites to relay distress signals.

The First Transatlantic Wireless Signal
Electromagnetic waves, or radio waves, were first transmitted across the Atlantic ocean in 1901 by Guglielmo Marconi. Marconi, considered the "father of radio," was an Italian inventor and entrepreneur. In a series of laboratory experiments and dramatic public demonstrations, he proved that wireless telegraphy could be used as a practical means of transmitting information. But sending a radio signal across the broad Atlantic would be the most dramatic demonstration yet of the power of the wireless. 

After setting up a transmitting station at Poldhu, in Cornwall, England, Marconi sailed to St. John's, Newfoundland, 2,100 miles away. There, he waited at his receiver for a signal to arrive. The operator at Poldhu began sending a sequence of three "dots," which represented the letter "s" in Morse code, on December 11. He repeated transmission throughout the day without success. The next day, December 12, Marconi detected a signal, although faint, at St. John's. Once again, the wireless had made history.

The First Wireless Distress Signals From Sea
The first wireless distress signal sent from sea was broadcast by a lightship -- a type of vessel which is anchored offshore and used as a communication port or as a "lighthouse" to warn ships of dangerous waters. In December, 1898, "East Goodwin Lightship," anchored off the southeastern coast of England, was struck by the "R. F. Matthews," which had lost its bearings in thick fog. A distress signal was immediately sent by wireless to the shore, and both vessels were secured. 

The first wireless distress signal to be sent from an American ship at sea occurred six years later, in 1905. "Relief Ship Number 58," a lightship anchored off Nantucket island, sent out the signal. This lightship hadn't been struck by another vessel; it had been battered by a treacherous coastal storm, causing leakage that threatened to sink the craft. 

The wireless operator on board "Relief Ship Number 58" used both International Morse code and American Morse code to transmit his message: "HELP!" A naval radio station in Rhode Island received the distress signal and dispatched the ship "Azalea" to the scene. By the time the "Azalea" arrived, it, too, had been roughed up by the storm. After a five-hour struggle to tow the lightship to shore, its crew-now practically swimming aboard their craft-were transferred to the "Azalea." Ten minutes later, "Relief Ship Number 58" went under.

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