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BELL SYSTEM TECHNICAL JOURNAL 



had to do with the electron interaction space and the resonator system. 

 Later, when driving equipment became available, life studies were started. 

 In the main this work showed the British design to be a very nearly opti- 

 mum as an unstrapped magnetron. Consequently the series of magnetrons 



4500 

 4400 

 4300 

 4200 



Q 



z 

 o 



'^ 3500 



a 



u 3400 



Q. 



<n 



y 3300 



> 



< 



o 



2 2200 



z 



5 2100 



z 

 u 



O 2000 



DC 



1400 

 1300 

 1200 

 1100 



tuner position in mm. 

 (measured from maximum intrusion) 



Fig. 59 — Curves of mode frequency variation with tuner position in the 5J26 mag- 

 netron. The curve for M = 4 is experimental, those for « = 1, 2, and 3 have been calculated 

 from an equivalent circuit theory of the resonator system (doublet structure nut shown). 

 Note the large mode frequency separation and the complete freedom of the ir mode from 

 interference by other modes (comi)are Fig. 56). 



having wavelengths near 10 cm. which were coded for American manufac- 

 ture were similar to the British prototype. The experiments and calcula- 

 tions which had been made constituted a body of valuable information to 

 be used later in departing from the original design. 



