214 



BELL SYSTEM TECHNICAL JOURNAL 



by the state of New Jersey but a conservative use of them indicates 

 that at a wave-length of 4.45 meters a phase difference of about 198 

 degrees exists between the direct and reflected components and the 

 resultant field should be about ?>\ per cent of that of a simple inverse 

 distance transmission. (The effect of air refr^iction is included.) This 

 is adequate for good reception at the McCatharn Hill. 



o -3 



20 30 40 



ANTENNA HEIGHT IN FEET 



Fig. 14— Local reflection at Beer's Hill. Horizontal 

 polarization X = 4.45 meters. 



Fig. 12 gives a profile of Beer's Hill along the line of transmission, 

 and Figs. 13 and 14 the McCatharn Hill reception as the transmitting 

 antenna was elevated. The hill slope is steeper here (Beer's Hill) and 

 the curves obtained for the original 40-foot (12.2-meter) structure 

 having indicated that the first oft-ground field minimum could be 

 reached with a little more height, an additional 20-foot section was 

 added to the lattice mast making it 60 feet (18.3 meters) high. The 

 difticulty of handling a low-loss bare wire transmission line, as the 

 height was varied, caused us to substitute a twisted pair incandescent 



