Prosign · CW procedural signal
SOS prosign in Morse code
The universal distress signal: three dits, three dahs, three dits — sent as one continuous shape with no inter-letter gaps.
Morse pattern
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Sent as one continuous shape — no inter-letter gap between the component letters.
Meaning
SOS — International distress
Notation
Written SOS but sent as one shape (no inter-letter gap).
When this is used
Reserved for actual emergency. The pattern was chosen at the 1906 Berlin Convention specifically because the rhythm is unambiguous under poor signal. NEVER send SOS for practice without making it clear it's a drill.
Examples
| On the air | Plain English |
|---|---|
| SOS SOS SOS DE <call> <call> POSITION… NATURE OF DISTRESS… | Standard distress format. |