Methoden zur kompensierung der wirkungen verschiedener arten von schroteffekt in elektronenröhren und angeschlossenen stromkreisen

Abstract

Section I shows, that the spontaneous fluctuations in circuits may under certain specified assumptions be considered as single wave alternating currents and voltages. The different kinds of spontaneous current and voltage fluctuations in electron tubes and attached circuits are discussed in section II. The underlying principles of the circuits, proposed for the suppression of spontaneous fluctuations are considered in section III. They all contain a special kind of feed-back. As a first compensating circuit in section IV the cathode current fluctuations are partially suppressed in the anode lead. Section V contains a circuit for the compensation of the current distribution fluctuations due to the action of the screen grid and section VI a circuit for compensating the emission fluctuations of a secondary cathode. At moderately high frequencies current fluctuations are induced in the (negative) input grid circuit and these are compensated and are used for compensating the cathode emission fluctuations in section VII. In section VIII the compensating circuits discussed previously are analysed as regards the ratio: signal voltage to fluctuation voltage. It appears, that this ratio may not be increased sometimes by compensating methods as set forth above, though the fluctuations themselves are greatly reduced in some parts of the circuits. Thus great care is recommended as regards such methods, if these are applied to new cases. An exact analysis of one of the circuits is given in the appendix, showing the order of magnitude of the terms neglected in the previous approximations.