Some Recent Measurements of Atmospheric Noise in Canada

Some recent atmospheric noise measurements in the vlf range have been made in Canada by the Defence Research Telecommunications Establishment of the Defence Research Board. The amplitude of the mean logarithmic power (mlp) of atmospheric noise on a frequency of 10 kilocycles has been measured at Ottawa, Ontario (Latitude 45.4° N, Longitude 75.9° W), over a period of one year, beginning in October, 1955. The mlp atmospheric noise amplitude has also been measured in the sub-Arctic regions of Canada at Churchill, Manitoba (Latitude 58.8° N, Longitude 94.2° W), on a frequency of 107 kc for the period December, 1955 to August, 1956. A brief description of the equipment used to obtain these measurements is described. The results of the measurements are presented in the form of a graphical analysis showing the hourly median variations. These measurements are compared with previous measurements made in Canada, and with the estimated values of the National Bureau of Standards, and CCIR predictions of July, 1956.