Accession Number : AD0257026

Title :   A STUDY OF CIRCUIT-INDEPENDENT OSCILLATIONS IN A GASEOUS CONDUCTOR

Corporate Author : CALIFORNIA UNIV BERKELEY ELECTRONICS RESEARCH LAB

Personal Author(s) : DOBRATZ,B.E.

Report Date : 15 FEB 1961

Pagination or Media Count : 1

Abstract : IN GASEOUS-PLASMA CONDUCTORS AN UNUSUAL TYPE OF CIRCUIT-INDEPENDENT, TIME-PERIODIC, LOW-FREQUENCY OSCILLATIONS OF CURRENT AND VOLTAGE CAN BE PRODUCED UNDER CERTAIN CONDITIONS. The effect is usually more pronounced at low currents and voltages near the threshold of conduction. A magnetic field is not necessary. The frequency generated is typically in the range of 1 kc to 1 Mc. The waveform may be sinusoidal or nonsinusoidal. Oscillations probably related to the type considered here are reported sporadically in the literature. The phenomenon was studied under controlled conditions. Oscillation amplitude and frequency were studied as functions of gas pressure, current, circuit capacitance and resistance, magnetic-field strength, and cathode temperature. A study of volt-ampere characteristics was made. The three classical explanations of oscillatory phenomena in gaseous conductors, (1) RC negative-resistance or circuit-controlled oscillations, (2) potential-minimum oscillations, and (3) ordinary plasma oscillations of space charge are analyzed and compared with experimental data obtained under controlled conditions. The phenomena observed appear to be definitely not related to (1) and probably not to (2) or (3). (Author)

Descriptors :   *OSCILLATION, *PLASMAS(PHYSICS), *PROPAGATION, *RADIO WAVES, CONDUCTIVITY, DISCHARGE TUBES, ELECTRICAL PROPERTIES, ELECTROMAGNETIC RADIATION, GASES, OSCILLATION, PLASMAS(PHYSICS), RADIOFREQUENCY

Distribution Statement : APPROVED FOR PUBLIC RELEASE