. The Bell System technical journal . th repeller voltage, arbitrary units. the oscillator were correctly terminated the characteristics departed vio-lently from the ideal, as illustrated in Fig. 19. Further investigation dis-closed that this departure was, to a greater or less degree, a general charac-teristic of all reflex oscillators in which no special steps had been taken toprevent it. The nature of this departure from expected behavior is that the output isnot a single valued function of the repeller voltage, but rather that at a givenrepeller voltage the output depends upon the directio
. The Bell System technical journal . th repeller voltage, arbitrary units. the oscillator were correctly terminated the characteristics departed vio-lently from the ideal, as illustrated in Fig. 19. Further investigation dis-closed that this departure was, to a greater or less degree, a general charac-teristic of all reflex oscillators in which no special steps had been taken toprevent it. The nature of this departure from expected behavior is that the output isnot a single valued function of the repeller voltage, but rather that at a givenrepeller voltage the output depends upon the direction from which the repel- 494 BELL SYSTEM TECHNICAL JOURNAL ler voltage is made to approach the given voltage. Consider the case illus-trated in Fig. 19. The arrows indicate the direction of repeller voltage vari-ation. If we start from the middle of the characteristic and move towardmore negative values of repeller voltage, the amplitude of oscillation variescontinuously until a critical value is reached, at which a sudden decrease in. NEGATIVE REPELLER VOLTAGE »- Fig. 19.—A possible variation of power and frequency with repeller voltage when thereis electronic hysteresis. The arrows indicate the direction of variation of repeller voltage. amplitude is observed. This drop may be to zero amplitude as shown or to afinite amplitude. In the latter case the amplitude may again decrease con-tinuously as the repeller voltage is continuously varied to a new criticalvalue, where a second drop occurs, etc. until finally the output falls to every observed case, even for more than one drop, the oscillation alwaysdropped to zero discontinuously. Upon retracing the repeller voltage varia-tion, oscillation does not restart at the repeller voltage at which it stoppedbut remains zero until a less negative value is reached, at which point the REFLEX OSCILLA TORS 495 oscillation jumps to a large amplitude on the normal curve and then variesuniformly. The discontinuities occur sometimes
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