Abstract :
The Sommerfeld, Austin, Fuller, and Eccles transmission formulas are compared with available data, and the conclusion reached that the Austin formula is most nearly correct. A chart is given whereby, given any five of the six quantities: wave length, transmitting and receiving antenna heights, distance of transmission, transmitting current, and received audibility, the sixth can readily be obtained. Tho specially intended for sustained wave reception using the ultraudion, it is shown that the chart can also be used for other detectors and damped wave reception.