With the development of modern radio communication technology, ships and spacecraft use Morse code for communication less and less. So SOS has gradually stopped except amateur radio and changed to GMDSS (International Maritime Satellite Electronic Communication Equipment).
Extended data:
1, which means
In fact, S.O.S is an international Morse code rescue signal, not the abbreviation of any single word. In view of the frequent maritime accidents at that time, it was often impossible to send out distress signals in time and organize rescue as quickly as possible, resulting in heavy casualties and property losses. The international radiotelegraph convention organization officially identified it as an international universal distress signal in 1908.
The combination of these three letters has no practical significance, just because its code (three dots, three dashes and then three dots) is most easily sent by the sender and recognized by the receiver in the telegram.
2. Sending method
Universal remote expression:
The first way to help: make a sound, three short three long three short (... _ _ _ _ _ _) Morse code.
Help method 2: lighting, such as flashlight, three short, three long and three short (switching lights)
Baidu encyclopedia -SOS distress signal