Teacher Resources: Morse Code Distress Calls

This is the second of a series of activities exploring Titanic and the Marconigraph.
They relate to the Wreck of the Titanic CD Rom> CQD-SOS>Sections 1-7

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At first, Titanic Marconigraph officers sent the message

CQD DE MGY


  • CQD was the Marconi company's distress signal to all vessels indicating that a ship needed help

  • DE meant 'from', or 'this is'

  • MGY identified the ship as the Titanic - its 'call sign'

By 1912, SOS had replaced CQD as the international distress call. This was because SOS was easily and instantly recognisable in morse: 'dit dit dit, dah dah dah, dit dit dit'. Children can prove this to themselves by translating, and speaking CQD in code.

However, Marconi operators still continued to use CQD. When ships were slow to reply Titanic's CQD calls, Harold Bride joked to radio officer Jack Phillips, 'Send SOS; it's the new call, and this may be your last chance to send it!

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Activities for the Classroom

Try making long and short sounds on chime bars. It's easy to make long sounds, but to make short sounds you will need to use your thumb to stop the bar vibrating.


  • Practise making long and short sounds on your chime bar

  • Now try to play the SOS call on your chime bar.

  • Can you repeat it several times without stopping?



Once you feel confident, find five or six other people with different chime bar notes. One player is a ship needing help, and sends the SOS message. Other players are ships relaying the message.


  • Try to send the message smoothly from one player to another.

  • Listen to the effect of the SOS rhythm played on the different notes.

  • Experiment with rearranging the notes in different orders

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Try this:The first player (ship in distress) carries on sounding SOS, and the second player joins in. This continues until everyone is playing the SOS.


  • Experiment with different ways of joining in

  • the last player could drop out, others following one by one until only the distressed ship is left sounding the emergency signal.

  • One person could act as conductor to tell each player when to start and stop

  • What happens when each player plays at different speeds so the SOS signals get jumbled up?


Research Opportunities
Children could explore the 'mayday' distress call used by aircraft.


Posted By admins| September 24, 2010 2:55 PM | | Categories: Resources | Comments (0)



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