Telecommunications in the First World War
The outbreak of the First World War meant that for the first time military priorities, like the censorship of telegrams and cables, had to overrule civilian ones for the government.
Military personnel could send and receive telegrams at cheaper rates, and the telegraph service was used to spread war news more quickly. Summaries were posted in outlying Post and Telegraph (P & T) offices. Some rural postmasters used the telephone for this purpose, for subscribers easily contactable via party lines, as at Kāwhia from September 1914.
P & T abroad and in New Zealand
Some 62 wireless telegraphists served in Mesopotamia (Iraq) during the war. By 1918, 850 female ‘temporaries’ were employed, many as telegraphists, to replace men on war service. The war also delayed the installation of rotary automatic telephony equipment until 1919, when the Masterton exchange trialled it. Ten years later main centres had all gone automatic.
Growing phone use
Between 1910 and 1950 the number of telephones grew more than tenfold – from around 33,000 to more than 350,000. Much of the growth took place in the interwar years.
Increasing suburbanisation was met and fostered by the spread of exchanges into suburbs. Enhanced carrier technology allowed more calls to be carried on each line by the use of wireless frequency modulation techniques. Private (from 1925) and rural (1929) automatic exchanges – PABXs and RAXs – increased government, commercial and rural use of phones.
In 1922/23, telecommunications revenues outstripped postal revenue for the first time.
The Murray multiplex
By 1925 telegrams sent between main centres were using the ‘Murray multiplex’, a higher-capacity, machine-printing system. It was invented by an expatriate New Zealander, Donald Murray, who had installed a prototype between London and Edinburgh some 20 years earlier.
Radio telecommunications from the 1920s
The 1920s also saw the tremendous expansion of radio for telegraphy, made possible by advances in short-wave radio. From 1921 to 1986 the P & T was the licensing authority for the use of radio frequencies for any purpose. From 1924 to 1930 it substantially upgraded its own maritime and general communications radio stations.
From 1936 ‘aeradio’ helped the navigation of fledgling passenger air services, and in 1937 the army even used radio-telephones to coordinate a mock battle. New Zealand subscribers could call the UK from 1931, but a three-minute call set them back nearly seven pounds – at least double the weekly wage for most.
Second World War
The advent of another world war saw strict censorship and, later, even greater employment of women in communications. There was a huge influx of women under the 1942 industrial conscription, or manpower regulations, with some 4000 employed by the Post and Telegraph Department by 1943. Abroad, 2nd Division signallers supported New Zealand forces in Crete, the Middle East and Italy. In the Gilbert Islands, eight of the Signal Corps radio operators, deployed as coast-watchers in July 1941, were among 22 New Zealand and British servicemen killed by the Japanese in October 1942.