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BELL SYSTEM TECHNICAL JOURNAL 



Fig. 42— Four fixed frequency magnetron oscillators. Theyare: (I) theojil magnetron 

 (60 kw., 24,000 mc/s); (2) the 4J52 magnetron (100 kw., 9375 mc/s); (3) the 720A-E mag- 

 netron (1000 kw., '-'2800 mc/s) ; (4) the 4J21-30 magnetron (600 kw., --1280 mc/s). Note 

 the two types of output circuit, coaxial and waveguide; the use of packaged magnets; 

 and the two types of input leads. 



quency from 700 mc/s to 24,000 mc/s.^^ In Fig. 42 is shown the external 

 view of four magnetrons of operating frequencies distributed over the range 



23 In this and other photographs of PART II either a one inch cube or a line of length 

 one inch has been included for size reference. 



