Communication & Codes

Quiz | Updated 3 years ago

In our modern world we are surrounded by codes.

At the station Ann swipes her ticket on the card reader and races across to catch the train. The train stops at her station. Ann picks up her backpack and tags off as she leaves the platform. As she strolls down the hill towards school Ann texts her friend Michelle.

  1. HB2U Ann
  2. JAD Michelle
  3. RUOK Ann
  4. GR8 (: Michelle
  5. T2YL Ann
  6. SYS Michelle

Codes are part of history too, particularly in times of war. The course of the Second World War was changed by the success of the Allied cryptographers in breaking Japanese codes and the German ENIGMA code.

However not all codes are secret. Some are open codes designed for rapid communication over distance, such as the ones initially used by Sydney and Kormoran when their paths crossed on the afternoon of 19 November 1941.

When HMAS Sydney (II) came across a mystery ship off the Western Australian coast the crew were on radio silence. So to try and discover the nationality of the other ship, Sydney signallers used a signal lamp to transmit Morse code. The other vessel responded using signal flags to reveal themselves as the Dutch ship Straat Malakka. Both codes – using Morse and the flags – were sent as open codes known to all mariners. But as Sydney closed in, they sent a secret code – known only to Allied ships – so they could be certain of the identity of the mystery vessel. Not knowing the secret code, Captain Detmers of the German Raider Kormoran raised his battle flag and answered with his guns…


Research Questions

  1. Find out about the code* Captain Detmers of the Kormoran used to hide his report and test it out on a friend.
    * For a brief account of the code read page 17 of HMAS Sydney – The Mystery of Australia’s Greatest Naval Disaster, Mike Lefroy Black Dog Books, 2009.
  2. Heraldry is an early example of a code being used for easy identification. Knights of old would wear certain colours and symbols to identify themselves. These became known as their ‘coat of arms’.
    Captain Detmers of the Kormoran didn’t reveal his ‘coat of arms’ (his country of origin) until he raised the German battle flag.
    Research the history of heraldry and design your own coat of arms. Explain the significance of each feature of your design.
    Research the use of deception and camouflage in wartime.
  3. Since the birth of mankind sign language using hand signals has been used as a way of communication. There are now hundreds of sign langauages in use around the world including many sports (such as football and cricket) where officals use standardised hand signals for some communication.
    Research the history of sign languages.
    Choose a particular one and explain how it is used as a form of communication.


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