||Technology in Australia 1788-1988
Table of Contents
I The First 100 Years 1788-1888
i Location of the Railway
iii Bridging and Tunnelling
iv Dams for Engine Water
v Locomotives and Rolling Stock
vi Signalling and Telecommunications
vii 1900/1988-The New Century
viii The Garratt Locomotive
ix Steam Locomotive Practice
x Motor Railcars
xii Electric Tramways
xiii Electric Railways - Direct Current
xiv Electric Railways - 25 kV ac
xv Diesel Traction
xvi Alignment and Track
III Motorised Vehicles
V Modern Shipping
VI Innovative Small Craft
SignallingThe application of established modern signalling techniques to suburban electrification schemes will be addressed later; it remains to review the development of main-line signalling technology in Australia from the Edwardian era practice of mechanical or power operated semaphores and points, and either manual instrument or automatic electric block, with electric staff instruments on single lines, to today.
The major visible developments in Australian railway signalling since then include colour-light signals; dc then ac then jointless high frequency track circuits; tuned reed and later multiplexed telemetry which made possible the remote control from a single panel of complete main lines (Centralised Traffic Control) and complexes of complicated interlockings in high traffic density territory (Area Signalling); track magnet operated automatic warning (the successor to train stops and tripcocks); and interlocking by miniaturised relays and switched contacts, instead of direct or power operated mechanical locks. All these developments were of overseas origin, and brought to Australia by the subsidiaries and licensees of the great signal engineering companies of the U.K., the U.S.A. and France.
Once again it was the application of these basic tools of technology that was Australian -and in some cases, the application was very innovative and novel. The use of computers in the control mode to store train descriptions and (if all is normal) to routinely select paths and direct the operation of points and signals, is one such instance. Lesser known is the development of computer-read system situation report-
Most of the real innovation in the decade to 1986, however, has been invisible. The pressure to economise in the use of interlocking relays (which are found by the thousand in complex area schemes and long CTC operated lines) has led to the abandonment of concepts of building one interlocking from multiple 'bricks' of standard functional assemblies, in favour of custom designing the circuits by computer, using CAD displays. Such innovations are novel and unlike the lineside signals and other hardware, are hidden in lineside 'location' huts, in downstairs relay rooms and even on the printed circuit boards in standard racks, that even to the experienced signal engineer, look much the same. Nonetheless, their use has made possible more extended application of modern signalling techniques in Australia than would have been economically possible as recently as 1975.
This trend is even more evident in the willingness to apply new technology, stimulated by economic pressures to avoid costly track circuits, relay complexes, and high volume data transmission lines in copper. Already all the Australian railways are using fixed microwave communications; several have fibre optic links in service and are seriously looking at radio operated single line safe-working; at least one uses Telecom STD links for electric staff operation and has reluctantly rejected train pinpointing location by satellite. Axle counting, and vehicle weighing by solid state transducer is the norm. Vehicle identification (automatic car identification) is likewise being applied.
The pressure for sound communications (in all forms, from teleprinter to data link) for effective operations has led the railways to replicate, in their own specialised systems, virtually every key communications technology found on the Telecom Australia networks -and to do this economically for (relatively) low volumes of intelligence. Increasingly, the electronic hardware is following the software in being Australian developed, as well as Australian made.
People in Bright Sparcs - Macfarlane, Ian B.
© 1988 Print Edition pages 470 - 471, Online Edition 2000
Published by Australian Science and Technology Heritage Centre, using the Web Academic Resource Publisher