TRANSATLANTIC RADIO TELEPHONY 



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reason, the longitudinal spacing in the modified longitudinal array 

 was decreased at the same time that the fourth antenna was con- 

 structed. 



At the time that the extension of the antenna system was under- 

 taken, the measured directional characteristics of the antennas A, B, 



Fig. 15 — Wave-antenna array directional characteristic. Calculated relative 

 directional receptivity of array of Houlton antennas ^, B, C, and D. (From average 

 measured unit antenna characteristic.) Dotted curve — magnified X 10. 



and D were available, so that the unit directional diagram for use in 

 determining this array characteristic was taken as the average meas- 

 ured characteristic of these three antennas. The calculated direc- 

 tional diagram of the complete Houlton antenna system is shown in 

 Fig. 15. It should be noticed that the scale for the back-end dotted 

 curve is ten times as great as that for the full-line curve for the major 

 lobe. 



