03/11/1906 Morse code distress signal "SOS" becomes worldwide standard
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SOS (THE SONG OF SONGS)
U.S. NAVY SIGNAL CORPS FLAG SEMAPHORE / BLINKER / MORSE CODE TRAINING FILM 85664
The Master Machinist: Andy Meyer (1908-1983)
SOS is the International Morse code distress signal the overscore indicates that the normal gaps between the letters should be omitted. It became the worldwide standard under the second International Radiotelegraphic Convention.