I was trained as a Marine Radio Officer a long time ago so this resonates with me, having been shipwrecked myself in the Indian Ocean.

CQD is morse code for All Stations - Distress, replaced a few years later with the better known SOS or Save Our Souls.   With Morse no longer used the voice distress is Mayday repeated 3 times with the vessels name and location.  It can now be sent automatically by satellite at the push of a button.

-.-.  --.-  -..  The Morse code for CQD

Public Service Broadcasting - Part 1 Building The Titanic 'The Unsinkable Ship' BBC Radio 1 B (3:13)
Public Service Broadcasting - Part 2 Setting Sail 'White Star Liner' BBC Radio 1 Biggest Week (3:53)
Public Service Broadcasting - Part 3 The Disaster 'C Q D' BBC Radio 1 Biggest Weekend [Video  (3:35)
Public Service Broadcasting - Part 4 The Wreck 'The Deep' BBC Radio 1 Biggest Weekend [Video  (1:30)
Public Service Broadcasting - Progress & The Gave Me A Lamp BBC Radio 1 Big Weekend [Video Al (4:05)
Public Service Broadcasting - Spitfire (BBC Radio 1 Big Weekend 2018) [Video Album] (4:06)
Public Service Broadcasting - Go (Apolo 11) (BBC Radio 1 Big Weekend 2018) [Video Album] (4:09)
Public Service Broadcasting - Gagarin (BBC Radio 1 Big Weekend 2018) [Video Album] (4:07)
Public Service Broadcasting - Everest (BBC Radio 1 Big Weekend 2018) [Video Album] (4:54)

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