TRANSATLANTIC RADIO TELEPHONY 351 



The cooperation of the engineers of the Wireless Section of the 

 British General Post Office, particularly Col. A. G. Lee and Mr. I. J. 

 Cohen, in the measurements made on wave-antennas in England and 

 Scotland, is greatly appreciated and we take this occasion to thank 

 them for having made possible the obtaining of these data. All of 

 our early work in connection with wave-antennas and our initial field 

 trials of lateral and longitudinal arrays of wave-antennas were carried 

 out using wave-antennas located at Belfast, Maine, and Riverhead, 

 New York. These antennas were made available through the courtesy 

 of the Radio Corporation of America, and the authors wish to express 

 to Mr. H. H. Beverage of that organization their appreciation for his 

 interest and assistance during the tests. 



APPENDIX 1 

 The Wave-Antenna 



Fundamentally, the wave-antenna consists of a straight horizontal 

 wire, terminated to ground at each end in its characteristic im- 

 pedance.^^ The determination of the receptivity characteristics of the 

 wave-antenna consists in determining the current flowing in the 

 terminal impedances of the antenna resulting from a field impressed 

 along the antenna. ^^ 



The wave-antenna is shown in Fig. 17, consisting of a line of length 

 5 extending from x = to x = s. In the nomenclature of the following 

 discussion, letters with no primes refer to the antenna, letters with a 

 single prime (') to the impressed field, and letters with a double prime 

 (") to the resultant field. The wave-antenna is in an impressed 

 electromagnetic field which is defined by the quantities 0', V, fw', 

 and fg' where 



(f)' = impressed magnetic flux between the lower surface of the wire 

 and the surface of the ground (per unit length) ; 



V = impressed electric force between the wire and the ground; 

 fw' = the impressed electric force along the lower surface of the wire; 

 fg' = the impressed electric force alofig the surface of the ground. 



The total field about the antenna is the sum of this impressed field 

 and a secondary field due to the currents and charges produced in the 

 circuit by the impressed field, so that 



(101) 



V' " 



'' J. R. Carson and R. S. Hoyt, "Propagation of Periodic Currents over a System 

 of Parallel Wires," Bell. System Tech. Jour., 6, 495; July, 1927. 



