Attenuation of Overland Radio Transmission in the Frequency Range 1.5 to 3.5 Megacycles per Second

Data on the effect of land upon radio transmission have been obtained during the past few years in connection with various site surveys. These data are for the general frequency range 1.5 to 3.5 megacycles per second and for various combinations of overwater and overland transmission as well as entirely overland. The generalizations in this paper are chiefly in the form of curves which enable one to make approximations of field strengths to be expected under the conditions noted above. The relation of these data to transmission in the broadcast frequency range is shown, and from the over-all picture, curves are developed which enable field strength estimates to be made for overland transmission in the extended frequency range.