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BELL SYSTEM TECHNICAL JOURNAL 



curve thus needs correction for the fact that the air Une distance 

 varied as the rod was lowered and raised. This correction is small 

 however. 



It will be observed that the maximum current occurs at 3.85 meters 

 and taking this value for determining the distance to the reflecting 

 ground surface gives, if we assume a radiation field only, 



(1.3 + 2hy + (770)2 = 



V1302 + 770- + 2 



or with X = 6.34 meters, h = 3.26 meters. The difference 3.26 

 — 2.55 = 0.71 meter is the apparent distance under ground of a 

 metallic sheet equivalent to the ground itself. 



WAVELENGTH IN METERS 

 Curve III — 250 cm. rod 



Curves II and III give the resonance curves of the 300 and 250 

 cm. rods respectively, mounted horizontally and 4 meters above 

 ground. The latter curve is complicated by two extraneous resonances 



