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BELL SYSTEM TECHNICAL JOURNAL 



the null point does not remain in the directional characteristic over a 

 band of frequencies. 



A directional diagram of a single antenna compensated to produce 

 a null point at 6 = 161.4 degrees (the bearing of the Rocky Point 

 transmitter relative to the axis of the antenna) is shown in Fig. 10. 

 This diagram was calculated, by the method outlined in Appendix 2, 

 from the average of the measured constants of Houlton antennas A, 

 B, and D. In this same figure, measured points are indicated, these 

 points being the average of observations on these three antennas. 



10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 

 360 350 340 330 320 310 300 290 280 270 260 250 240 230 220 210 200 190 180 



ANGLES OF INCIDENCE (e) — DEGREES 



Fig. 10 — Wave-antenna directional characteristic. Relative directional receptivity 

 of compensated average Houlton antenna. (Short.) 



Beverage, Rice, and Kellog ^* have shown that there are important 

 practical advantages to be gained by constructing the wave-antenna 

 as a two-wire line, and using the metallic circuit acquired thereby as 

 a transmission line to bring the output from one end of the antenna 

 to the radio receiver. The circuits used to bring the output currents 

 from the two ends of the wave-antenna to the radio receiver are shown 

 in Fig. 11. In this case, the radio receiver is located at the initial 

 end of the antenna, so that the predominant desired signal currents 

 are transmitted over the metallic circuit of the wave-antenna to the 

 radio receiver, while the compensation currents are taken directly 

 from the initial end termination when this form of array is used. 



To obtain a greater reduction in the Noise Reception Factor (defined 

 under "Directional Discrimination Against Static" earlier in this 

 paper) than is given by compensation, two or more parallel wave- 



