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BELL SYSTEM TECHNICAL JOURNAL 



opening of commerical service last December. A photograph of the 

 receiving set is shown in Fig. 7. The receiver is of the double-detec- 

 tion type, of high gain and selectivity, and employs screen-grid tubes. 

 It is provided with automatic gain control. The apparatus shown 

 includes not only the receiving set proper but also the equipment which 

 is required for monitoring the circuit and for connecting with the wire 



Fig. 7 — Forked River receiving set. 



line into New York. The receiving antennas are of the same general 

 type as those used in the transatlantic system, which consist of a row 

 of quarter-wavelength verticals connected alternately top and bottom 

 by quarter-wavelength conductors. In the case of the longer wave- 

 lengths used in the ship-to-shore service, the vertical conductors are 



