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BELL SYSTEM TECHNICAL JOURNAL 



value Vi . Under these conditions the power output will appear as shown in 

 Fig. 24, in which the hysteresis is apparent. 



Let us now consider the conditions obtaining in a reflex oscillator. Fig. 

 1 shows a schematic diagram of a reflex oscillator. This shows an electron 

 gun which projects a rectilinear electron stream across the gap of a resonator. 



AMPLITUDE OF OSCILLATION, V — — *■ 



Fig. 23. — Variation of electronic conductance with amplitude of oscillation of a form 

 which will result in hysteresis. The parameter A' determines the small signal value of the 

 conductance. The horizontal line indicates the load conductance. 



After the beam passes through this gap it is retarded and returned by a uni- 

 form electrostatic field. If we carry out an analysis to determine the elec- 

 tronic admittance which will appear across the gap if the electrons make one 

 round trip, we arrive at expression 2.2 which may be written 



Fe = 



lo^'eMX) 



[sin 6 -\- j cos d] 



(8.7) 



where 



X = 





