REFLEX OSCILLATORS 



559 



This design was superseded later by the W.E. 2K25 which has a greater 

 frequency range and a number of design refinements. From a construc- 

 tional point of view the two types are closely similar, however, and to avoid 

 duplication the later tube will be described to typify a construction which 

 served as a basis for a whole series of oscillators in the range from 2500 to 

 10,000 Mc/s. 



Fig. 62. — An early continuous!}' pumped metal reflex oscillator tuned with an 

 external line. 



Before proceeding to a description of the 2K25 tube it seems desirable to 

 recapitulate in more detail the design objectives from a mechanical point 

 of view. These were: 



1. To provide a design which would lend itself to large scale production 

 and one sufficiently rugged as to be capable of withstanding the rough 

 use inherent in military service. 



2. To provide output means which permit coupling to a wave guide in 

 such a manner that installation or replacement could be accomplished 

 in the simplest possible manner. 



3. To provide a tuning mechanism for the resonant circuit which, while 

 simple, would give sufficiently fine tuning to permit setting and holding 



