August 11, 1909: The Arapahoe, an American ship out of Cape Hatteras, NC, used CQD (All Station Distress) before using SOS, the international distress call. The SOS signal was received by the United Wireless Telegraph Company station at Hatteras, North Carolina, and forwarded to the steamer company's offices CQD was later replaced by the SOS code, which was sent as three separate letters with spaces between each letter.
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