Pattern A Day / 365 Patterns – #17 SOS. SOS From Wikipedia, the free encyclopedia For other uses, see SOS (disambiguation). is the commonly used description for the international Morse code distress signal (· · · – – – · · ·). This distress signal was first adopted by the German government in radio regulations effective April 1, 1905, and became the worldwide standard under the second International Radiotelegraphic Convention, which… Continue reading Pattern A Day / 365 Patterns – #17 SOS