The vodas
S. B. Wright · Bell System Technical Journal · 1937
Since the first transatlantic radio telephone circuit was opened for service over ten years ago, an increasing number of voice-operated switching devices has been added to the international telephone network. All of these have the common purpose of preventing echo and singing effects due to arranging the facilities to give the best possible transmission, even under difficult radio conditions. Differences in the design and performance of the several types of devices suggest that the advantages and disadvantages of each be made available. The characteristics of two types of “vodas” used on circuits connecting with the United States are described in this paper. For reference purposes, a complete list of Bell System papers relating to these devices is included.