RADAR ANTENNAS 



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experimental antenna shown in Fig. 26 was one of the first to illustrate the 

 practicality of this design. 



The horizontal pattern of the 7' x 32' antenna is plotted in Fig. 27. The 

 horizontal beam width is seen to be of the order of 0.7 degrees. 



The antenna illustrated in Fig. 26 is interesting in another way for it is a 

 good example of a type of experimental construction which was extremely 

 useful in wartime antenna development. Research and development engi- 



2 2 4 6 



DEGREES 

 Fig. 27 — 7' X 32' Antenna, Horizontal Pattern. 



neers found that they could often save months by constructing initial 

 models of wood. Upon completion of a wooden model electrically im- 

 portant surfaces were covered with metal foil or were sprayed or painted 

 with metal. Thus, where tolerances permitted, the carpenter shop could 

 replace the relatively slow machine shop. 



Another form of parallel plate line feed results when a plastic lens is placed 

 between parallel plates and used as the focussing element. A linear array 



