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BELL SYSTEM TECHNICAL JOURNAL 



I 16 



5 

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64 66 



68 70 72 74 76 78 80 82 84 

 HALF OF SIDE INTERIOR-ANGLE IN DEGREES 



Fig. 4— Steerability, at several wave-lengths, of the horizontal rhombic antenna 

 used for the fading reduction studies. The antenna element lengths were 184 meters 

 and their height 19 meters. 



employed in the antenna. The power-winch was equipped with auto- 

 matic safety stops at the extreme positions, also with a potentiometer 

 which was coupled to the winch to permit the use of a voltmeter as an 

 antenna position indicator. This position indicator was located at the 

 operator's position. By using counterweights, the required size of the 

 winch motor is reduced. 



The adopted system for observing selective fading requiri'd a fre- 



