REFLEX OSCILLATORS 



581 



TUNER BOW 

 TUNER CHANNEL- 



REPELLER 

 DIAPHRAGM CONNECTOR 



FLEXIBLE DIAPHRAGM 



RESONATOR 



HEAT BLEEDER- 



FOCUSING ANODE 



BEAM -FORMING 

 ELECTRODE 



Fig. 77. — A section of the W.E. 2K45 cut parallel to the tuner cathode and strut. 



positive action in a device which has thermal inertia. What is actually 

 meant, however, may be best indicated by the following: Let us suppose that 

 some power, Pa must be dissipated in the tuner in order to hold the oscillator 

 at a frequency, /„ . Now, suppose that the tube is operating with power 

 less than Pa and that we are required to switch to frequency /„ . In order 

 to switch rapidly, we apply power in excess of Pa to the tuner until the fre- 

 quency has reached fa , at which time we switch to the power Pa required 



