Transoceanic Telephone Service — Short-Wave Equipment 



A. A. OSWALD! 



The application of short-wave radio transmission to transoceanic tele- 

 phone circuits is developing apparatus and stations designed specifically to 

 meet the needs of these services. This paper describes from the radio point 

 of view the important technical features and developments incorporated in 

 the new transmitting and receiving stations of the American Telephone 

 and Telegraph Company located respectively at Lawrenceville and Netcong, 

 New Jersey, and it outlines some of the radio problems encountered in the 

 station design. 



***** 



SHORTLY after transatlantic telephone service was opened in 

 January, 1927 the long-wave radio circuit between New York and 

 London was supplemented, first by an experimental short-wave radio 

 link in the west-east direction and later by a short-wave link in the 

 east-west direction.^ From this beginning, as an auxiliary to the long- 

 wave circuit, the short-wave system has been improved steadily so that 

 its average performance throughout the year now more nearly ap- 

 proaches that of the long-wave system and it has become an important 

 part of the transoceanic facilities. The relative merits of the two sys- 

 tems, their combined usefulness, and their transmission features are 

 the subject of another paper and will not be discussed here. For the 

 present purpose it will be sufficient to note that there are now in opera- 

 tion between New York and London, one long-wave and three short- 

 wave two-way circuits and that within a few weeks a short-wave circuit 

 will be available between New York and Buenos Aires. 



The radio transmitting units for the New York end of these four 

 circuits are located at the new station which the American Telephone 

 and Telegraph Company has recently established at Lawrenceville, 

 New Jersey. The receiving units are concentrated at Netcong, New 

 Jersey. The factors entering into the selection of these station loca- 

 tions are outlined in another paper and therefore need not be men- 

 tioned further. This paper is limited in scope to a necessarily brief 

 description of the transmitting and receiving systems and apparatus, a 

 discussion of technical features in the station layouts, and an outline 

 of the major problems encountered in the station design. Comprehen- 

 sive treatment of individual units is properly left for other entire papers. 

 It will be convenient to deal with the transmitting and receiving sta- 



^ Presented at the Winter Convention of the A. I. E. E., New York, N. Y., Jan., 

 1930. 



a O. B. Blackwcll, A. I. E. E. Journal, May 1928. B. S. T. J. April 1928. 



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