New Telephone Equipment Installed at Tumut 

Will Eliminate Delays in Trunk Calls To and Via Wagga

25 July 1950 The Tumut and Adelong Times

During the past few months additional trunk-line telephone equipment has been in the process of installation at the Tumut Telephone Exchange which has and will further greatly alleviate the delays previously experienced on trunk-line calls to and from Wagga.

A modern three-channel carrier-wave system has been installed at both ends, and this replaces the single channel system which, up until recently, was the only direct trunk outlet between Tumut and Wagga. 

This equipment employs the principles of modern radio telephony and by undulating and demodulating the voice frequency with a different carrier-wave frequency for each channel three separate trunk-line conversations can be in progress between Wagga and Tumut at the same time on the one pair of wires without any interference or cross-talk from one another. 

There are larger types of systems used in very busy centres which will allow for twelve conversations and a number of telegraph circuits to be in progress simultaneously on the same pair of wires. 

With the completion of the installation of additional equipment at Tumut last week one of these new trunk-line channels to Wagga was converted to a voice-frequency dialling circuit.

This now means that the telephoniste at Tumut has direct access to Wagga automatic telephone subscribers and can dial the numbers direct from here, which reduces delay considerably, whereas previously the numbers had to be obtained through the telephone operator at the other end dialling the required numbers.   

A single-channel carrier-wave system is also in the course of installation at Batlow, and when completed and linked with another channel via Tumbarumba and Wagga, will provide a direct trunk circuit between Batlow and Wagga trunk exchanges. 

These carrier-wave systems are of an extremely delicate and intricate nature and each channel has to be adjusted and synchronised regularly by the technicians at both ends of the circuit to ensure efficient operation.