Simultaneous Transmission and Reception in Radio Telephony

After reviewing the methods of duplex radio communication previously proposed, the author describes a divided-branch antenna arrangement with supplementary balancing coil, for this purpose. The theory and mode of adjustment of the system are explained. The application of this method in practice to ship-to-shore radio telephony is described, and reference is made to the necessary wire-to-radio and reverse transfers. Guided radio telephony and telegraphy over high tension transmission lines is considered. The use of a single oscillation generator for a number of stations is shown to be possible. An actual transmission of this type is described in detail.