The Diurnal and Seasonal Performance of High-Frequency Radio Transmission over Various Long Distance Circuits

This paper presents a quantity of radio wave propagation data that has been obtained during the past six years by the General Electric Company through the use of its developmental transmission facilities at South Schenectady, New York. Nineteen radio circuits which radiate in various directions from Schenectady are treated. These circuits range in length from 2300 to 11,400 miles. Data are given which will aid in determining the proper frequency to use in any high-frequency radio circuit from 1000 to 10,000 miles in length. It is shown that the daylight-darkness distribution over the path of propagation largely determines the diurnal and seasonal performance of high-frequency transmissions.