203 emergency sos satellite system based on cell phone satellite connections. sos from wikipedia, the free encyclopedia sos 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 radio telegraphic convention, which was signed on november 3, 1906 and became effective on july 1, 1908. sos remained the maritime radio distress signal until 1999, when it was replaced by the global maritime distress safety system. [1] (with this new system in place, it became illegal for a ship to signal that she is in distress in morse code. citation needed]) sos is still recognized as a visual distress signal.[2] from the beginning, the sos distress signal has really consisted of a continuous sequence of three-ditz/three-dash/three-ditz, all run together without letter spacing. in international morse code, three ditz form the letter s, and three dash make the letter o, so "sos" became an easy way to remember the order of the ditz and dash. in modern terminology, sos is a morse "procedural signal" or "pro sign", and the formal way to write it is with a bar above the letters: sos in popular usage, sos became associated with such phrases as "save our ship", "save our souls" and "send out succor". these may be regarded as mnemonics, but sos does not stand for anything and is not an abbreviation, acronym or initials. in fact sos is only one of several ways that the combination could have been written, vtb, for example, would produce exactly the same sound, but sos was chosen to describe this combination. sos is the only 9-element signal in morse code, making it more easily recognizable, as no other symbol uses more than 8 elements. copyright © 2017 christopher g brown patent christopher g brown 3359 2574 createspace independent publishing platform (july 26, 2013) isbn-13: 978-1491202777