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BELL SYSTEM TECHNICAL JOURNAL 



at Riverhead, L. I., as shown in Fig. 5. The receiving antenna was 

 not tuned but was connected to the radio receiver through fixed 

 inductive coupling. 



The carrier power in the transmitting antenna normally remains 

 fairly constant, except for minor variations in voltage of the supply 

 mains, and with a little care on the part of operating personnel, the 



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Fig. 4 — -Plan — elevation of the transmitting antenna 



antenna current can be kept within the limits of a 1 per cent, varia- 

 tion, which is small compared with the signal fading usually ex- 

 perienced. 



The stabilization of the frequency was of the greatest importance 

 since in some of the tests it was desired to beat or heterodyne the 

 signals down to audio frequencies and pass them through narrow 

 band filters. To provide this stability engineers of the Bell Telephone 

 Laboratories arranged the 5-kw. transmitter at station 2XB to obtain 



