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BELL SYSTEM TECHNCLAL JOURNAL 



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Fig. 58. — External view of the W.E. 707-A reflex oscillator tube. This tube is intended 

 for use with an external cavity and was the first of a series of low voltage oscillators. 



trode and an accelerating electrode Ch which is a mesh grid formed on a 

 radius. 'J'he gun design is based on the principle of maintaining boundary 

 conditions such that a rectilinear electron beam will flow through the 

 resonator gap. The resonator grids Gi and G3 are mounted on copper discs. 



