Abridgment of transoceanic telephone service — Short-wave transmission: Transmission features of short-wave radio circuits

The discussion relates to the transmission problems involved in short-wave radiotelephony over long distances, and the transmission bases for design of the systems used in commercial transatlantic service. Choice of operating frequencies, amounts of transmitter power, directive transmitting and receiving antennas, automatic gain controls in receivers, and voice-operated switching devices are all factors which may be invoked to aid in solving these problems. The way in which they have been applied in the transatlantic systems and the results which have been obtained are set forth briefly.