Communication During War - military communication during World War II

During the Second World War military forces had signals units whose role was to operate wireless radios, lay and repair heavy telephone cables, and transmit messages using visual signals like flags (semaphore) and signal lamps

As the war developed in north west Europe, signals units laid hundreds of miles of telephone and telegraph cables. They also made use of civilian networks wherever possible. Communications to the United Kingdom were made via a cable laid under the Channel connected to signal stations at Bayeaux and Cherbourg in France.

 Many developments were made for radio communication during the Second World War.

Wireless set no. 108 developed for Australian Army 1941

In 1942 the Wireless Set no. 10 - a mobile radio station containing eight duplex telephone channels over a radio (microwave) line of sight link was developed (below).

During the North African signal units had to lay and retrieve telephone cables and establish wireless links at great speed. Valuable lessons learned in the desert helped in the mobile warfare after the Normandy landing in June 1944.

Wireless radio set

When we were in London in 2015 near our hotel there was a memorial to the SOE (Special Operations Executive). The plaque on the memorial read - The SOE 'was secretly formed for the purpose of recruiting agents, men and women of many nationalities who would volunteer to continue the fight for freedom by performing acts of sabotage in countries occupied by the enemy during the Second World War.' Those chosen for such missions were taken to France, for example, in a small plane and left in an isolated location to be collected by partisans with whom they would be working. Communication with headquarters in London was made sending coded messages via radio at a specified time.

SOE mobile radio

Many books, including historical fiction have been written based on the experiences of women in the SOE. 

Morse code and other systems of coding continued to be used during the Second World War.  Florence Violet McKenzie (Mrs Mac) funded and established the volunteer Women’s Emergency Signals Corps in Sydney in 1939 to train women in wireless telegraphy, signals and international codes. 

Mrs Mac

An important role during the war was to decipher enemy messages sent in code. In England Bletchley Park was the primary location used for code breaking. Teams of staff worked day and night to intercept messages, decode them and then pass the message on to military personnel. The biggest challenge occurred when the Germans sent their messages using an Enigma machine using codes that kept changing each day. Eventually Alan Turing and his team managed to break the codes.

Decoding machine - Turing Bombe

There were also code breakers in Australia working for the Central Bureau. The headquarters were in Melbourne but much of the work was carried out in a garage in Brisbane by a group of women. The Garage Girls used 12 British-made TypeX coding machines to both decode and encrypt highly classified material.

A number of non-fiction and novels have been written about the important work of the  codebreakers in Australia and at Bletchley Park.

Another area where scientists played an important part in assisting the military was in the study of radar. During the Second World War the Telecommunications Research Establishment occupied a school in Malvern, England. Many important advances in developing radar systems to assist the military effort were made.

Radar to monitor aircraft