The SOS distress signal does not stand for anything. The … _ _ _ … was easy to transmit in Morse code. Before the standardisation of an international distress signal in July 1908, other countries had their own signals. Germany used SOE, Italy SSSDDD and Britain transmitted CQD.

At the Berlin conference, it was recognised that in Morse code the letter E was represented by one dot (.) and could be mistyped.

The E was replaced with an S as three dots (…) was clearer. Although the SOS signal was officially adopted in 1908 and used successfully in July 1909 when a shipwrecked occurred in Portugal, it was not used in April 1912.

That fateful night, the Titanic radio operator first transmitted the old CQD distress signal. Only afterwards did he try the new signal, commenting that he might never get the chance to try it again.

Although Morse equipment has been replaced at sea by the Global Maritime Distress and Safety System, it is still useful to know some emergency Morse signals.

6 Everyday radio calls in Morse

1. Starting: _ . _ . _ .
2. Over: _ . _
3. Wait: . _ . . .
4. Roger: . . . _
5. End: . . . _ . _
6. Error: . . . . . . . .

Learn this skill and other means of signalling for help on one of our courses.
H.E.A.T. tip: If you are unlawfully detained, blink your eyes in Morse code and communicate without alerting your captors.