【摘要】 <正> 一、引言双三极管阴极耦合負阻振蕩器是近年来頗受人注意的一种振蕩器。它的頻率范围很寬,从几十赫至几百兆赫;频率稳定性很高;构造簡单,消耗功率小。适于作为輸出功率較小的振荡器(如仪器中)或激励器应用。更多还原

【Abstract】 In this paper the theoretical analysis, calculating methods and experimental results of the cathode-coupled twin-triode negative resistance oscillator are given. An equation expressing the negative resistance by the tube eanstants, plate resistance, cathode resistance and source voltage is derived. The methods of the negative resistance measurement are described and some results are shown. A graphical method deriving the negative resistance curve directly from the tube characteristics is developed. The authors indicate that the measured negative resistance characteristics are more precisely approached by an approximate expression with a term of fifth power than that of only third power. The non-linear differential equation of a LC sinusoidal negative resistance oscillator, using the fifth power approximation of negative resistance, is derived and solved. Two graphical methods for amplitude calculation are developed. The frequency stability and amplitude stability of the negative resistanee oscillator are studied theoriteally and experimentally. The experimental results of the effects of the source voltage, plate resistance, cathode resistance, heater voltage and the cathode by-pass condenser on the freqeney stability are shown. It is indicated that of the plate resistances and cathode by-pass condensers there are optimum values, at which the maximum frequency stability is obtained. The experimextal results of the effects of the source voltage, the Q of the tank circuit and the heater voltage on the amplitude stability are also shown.更多还原