197103 – McCamley & Meyers – New South Wales Railways: Sydney-Orange Microwave Link

The main purpose of this composite paper is to introduce the subject of “Microwave Link Transmission” as a new technique to the existing Departmental practice of using carrier telephone systems for the transmission of trunk communication services over open wire lines and cables.

It is intended to explain how the Microwave Link, referred to in this paper, was obtained and installed, as a bearer channel, between Sydney and Orange, for the transmission of 24 trunk telephone channels between these centres, and, at the same time, part provide for the future expansion of the system to Goulburn.

In order to present the subject, in a manner which may allow a better appreciation to be made of the function of the Sydney to Orange Microwave Link, the paper has been prepared in the following two (2) parts:

PART I.
The first section of this paper deals with various aspects of the initial planning of the system and its subsequent provision. An introduction is also made to the function of the overall system and the carrier multiplexing equipment.

PART II.
This section of the paper examines, in a general way, factors affecting propagation at 1500 MHz, the band used for the Sydney to Orange route, also, System Planning – The Specification – Description of the Work – The Radio Link Equipment – and an introduction to testing techniques applicable for system evaluation.