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EAST-WEST TELEPHONY



It is now well over 85 years since the establishment of a telephone link between Western Australia and the eastern states. A conversation on December 18th 1930 between Western Australian Premier Sir James Mitchell and Federal Postmaster General Joseph Lyons began an important era in Australian communications.

Mitchell in Perth and Lyons in Melbourne made the first official telephone call between Australia's east and west. The conversation was made possible by a two-wire voice frequency repeated single circuit which also hosted a 10-channel telegraph system.

The voice link came into use more than half a century after the first electrical communication - the Intercolonial Telegraph - opened on December 8th 1877. Two further wires were added in 1896 and another in 1905 but the lines, which followed the coast and passed through Eucla, were subject to recurring insulation problems due to sea mists.

When the transcontinental railway was being built from Kalgoorlie to Port Augusta the PMG's Department paid the Commonwealth Railways 25,000 to reduce the pole spacing to allow a telegraph line to follow the track. Future PMG wires would thus be better supported. Three copper conductors were erected by the PMG on this route and in March 1927 interstate telegraph traffic was transferred from the Eucla route to these new wires.

Mounting pressure for an east-west telephone link led to the formation, early in 1929, of a Federal Parliamentary Committee to look into the matter. The Committee handed down a favourable recommendation in August that year, estimating the cost of one Perth-Adelaide telephone trunk at 70,000.

It was proposed that one voice frequency (VF) repeated circuit be installed between Perth and Adelaide. Telegraphs would be carried by a higher frequency carrier circuit equipped with ten duplex channels occupying the frequency range of 3.3 to 10kHz on the same pair of wires. Seven repeater stations were required.

Western Australia had also been pressing for sound broadcasts to be relayed from the east. At first the telephone trunk was occasionally used to relay speech broadcasts but its bandwidth could not handle musical programs. In 1933 a Standard Telephones and Cables Pty. Ltd. Broadcast line carrier system manufactured to PMG specifications at a cost of 1,700 was installed.

Demand for more than the single east-west telephone line did not occur until late in the 1930s. The outbreak of World War II increased the pressure and in 1941 the War Cabinet authorised a vote of 150,000 for upgrading east-west communications. Significant items were a fourth wire to run from Port Augusta to Kalgoorlie and two three-channel carrier telephone systems Perth-Adelaide to replace the single 1930 circuit which was still the only channel available.

Work started in 1942 on running the extra wire and also on establishing a three-channel carrier telephone system on the existing pair. The first system was placed in service in October 1942 but, due to wartime shortages, it was not until July 1945 that the second system was ready. At the end of the war there were 5 east-west telephone circuits and a sixth channel for telegraphs.

In postwar years demand for extra transcontinental circuits increased and early in 1954 two 12-channel open wire carrier telephone systems were completed, one Perth-Kalgoorlie and the other Kalgoorlie-Port Augusta. In February 1954 six of these circuits were through-connected for interstate use.

By 1958 there were two extra copper pairs between Port Augusta and Kalgoorlie. All pairs carried 12-channel systems and the pole route was stayed to withstand high winds at a total cost of 750,000.

By the end of 1963 the route carried a further two 12-channel systems but more were required. While it was recognised the pole route was in good condition represented a substantial asset it was obvious that long-term needs would need a new approach.

In 1966 a $10 million contract for a 2GHz microwave radio system between Northam (WA) and Port Pirie (SA) was let to GEC (Australia) Pty. Ltd. Over the 2300km route there were to be 60 repeaters for the main 600-channel telephony bearer and its standby bearer. The latter was also to carry interstate TV as required.

By mid 1969 the transcontinental open wire route reached its maximum capacity of 104 telephone circuits and about 15 channels used for telegraphs, broadcast and private lines.

The east-west microwave came into service on July 10th 1970 bringing to WA not only extra channels but also STD to other capitals and the ability to send or receive TV programs across the nation.

In 1981 there were about 1100 telephone circuits for public use plus hundreds of circuits for other uses. Today, in the digital age, there are many thousands of virtual circuits linking Western Australia with the rest of Australia and the world. A far cry from the single pair of wires following the long straight railway line across the Nullabor in 1930.

From article by John Moynihan in "Engineers Australia", December 1980 - January 1981.



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