Omega and EM exploration

Abstract

There have been reports recently of interference with EM measurements in the Gippsland area, presumably as a result of Omega site evaluation. In reply to my query, the Minister for Transport, Mr. Nixon, provided the following information (see attached diagrams): "As you are probably aware, seven of the intended eight Omega transmitting facilities are currently in operation. The Australian facility, when it is commissioned will complete the world-wide network. The radio frequencies that are currently being transmitted are shown in the Omega signal format in the attached figure 1. The frequencies are not radiated continuously by each station but only for a segment of time in the 10 second cycle, for example Norway radiates on 10.2 kHz followed by 13.6 kHz and then 11.333 kHz followed by five blank segments. The final signal format has not yet been established and will be an agenda item at a forthcoming Omega Technical Conference in Japan. At this point in time the proposed final signal format is shown in the attached figure 2. You should note that the Australian facility will occupy the Station G position in the signal format.'' The objectives of this note are to bring the matter to the attention of others who may be having difficulty for reason of these tests, and to point out some implications of the developments.