||Technology in Australia 1788-1988
Table of Contents
I Part 1: Communications
i Before the Telegraph
ii Electrical Communication Before Federation
iii Federation to the End of the Second World War
iv Post-war and on to 1975
v 1975 ONWARDS
III Part 2: Early Australian Computers And Computing
Federation to the End of the Second World War (continued)Early in the war period, expanding the trunk and telegraph system was a high priority, a task which received added urgency as the threat grew of the war extending to the Pacific Region. One major task was strengthening the route from Adelaide to Darwin and erecting a pair of copper wires as the bearer for carrier equipment required for improved communications to the Northern Territory. When Australia became the base for American and Australian forces in the Pacific Campaign, it was necessary to greatly expand trunk line facilities. The plan developed included upgrading the open wire routes from Adelaide to Melbourne and then north through Sydney and Brisbane to Townsville, to take 12 channel systems, with capacity for the installation of four such systems in the Sydney to Melbourne section a requirement. Details of the AT&T company's Jl and J2 systems were available but were based on 6.4 mile E sections, which in turn depended on transposition pole spacings of four chains. Australian routes in general had not been constructed to these specifications and pole spacings gave E sections of around eight miles.
Detailed theoretical calculations were undertaken in order to determine the best transposition types to use and were supported by construction of trial E sections with subsequent transmission measurements, but translating these results to very long routes with many irregularities involved many difficulties. Third circuit effects due to phantom transpositions on lower arms were found to be a problem and had to be eliminated. Fig. 14, which shows the system adopted for a typical E section is taken from an account by W. H. Walker who played an important part in the design work. Extensive construction work was involved on the main coastal trunk routes and, particularly in Queensland, in building up alternative inland ones. These projects often saw personnel from the Services working under technical direction from P.M.G. staff.
Materials for the construction programmes were reasonably available but supplies of telegraph carrier equipment, which had been fully imported, were no longer available from these sources. The Research Laboratories, the PMG Workshops, STC and various subcontractors, were all utilised to produce a series of four, six and nine channel VF telegraph systems, with the first coming into service early in 1942. Many individuals contributed to the success of this major project, with E. H. Palfreyman and W. N. Boswell of the Laboratories undertaking the design of items such as filters and oscillators. Mobile systems were also produced for the Services.
In addition to designing and manufacturing a range of items, the Workshops modified equipment, such as teleprinters secured from the USA, to meet local network conditions. The staff of the PMG were extensively involved also in re-arranging working circuits and equipment to meet Service and Civil needs and A. Moyal has described some of the activities involved. Although the Department was classified as a reserve occupation, some staff joined the Services, many to undertake communications work and there was a similar drain on industry manpower. In another contribution to manpower needs, the Marconi School of Wireless, established in 1913 by AWA, provided training in wireless communications for 4730 service personnel and 385 radio officers for merchant ships.
Organisations in Australian Science at Work - Amalagamated Wireless Australia (A.W.A.); Marconi School of Wireless; Standard Telephones and Cables (S.T.C.)
People in Bright Sparcs - Boswell, W. N.; Moyal, A.; Palfreyman, E. H.; Walker, W. H.
© 1988 Print Edition pages 558 - 559, Online Edition 2000
Published by Australian Science and Technology Heritage Centre, using the Web Academic Resource Publisher