Morse code encoded the same way (A, O, E, I, T, M, N, R, K, etc.). Bulgarian alphabet contains 30 characters, which exactly match all possible combinations of 1, 2, 3, and 4 dots and dashes. Russian requires 1 extra character, "Ы" which is encoded with 5 elements. During early World War I (1914–1916), Germany briefly experimented with 'dotty' and 'dashy' Morse, in essence adding a dot or a dash at the end of each Morse symbol. Each one was quickly broken by Allied SIGINT, and standard Morse was restored by Spring 1916. Only a small percentage of Western Front (North Atlantic
SOS and became effective on 1 July 1908. ' remained the maritime radio distress signal until 1999, when it was replaced by the Global Maritime Distress and Safety System. ' is still recognized as a standard distress signal that may be used with any signaling method. The distress signal is a continuous sequence of three dots, three dashes, and three dots, with no spaces between the letters (notated by the overscore). In International Morse Code, three dots form the letter "S", and three dashes make the letter "O", so ""S O S"" became a way to remember the order of the