Cold Cathode Tubes for Transmission of Audio Frequency Signals

Abstract

Cold cathode gas filled tubes have been extensively applied as electronic switching elements in the telephone system. In general, these applications have been limited to control circuits. The usefulness of these tubes can be further extended by making them capable of carrying voice frequency signals. The transmission properties that are required of the tube for this use are considered. It is shown that troublesome oscillatory noise can be eliminated and that the insertion loss of the tube can be reduced to a low value. Furthermore, by a special design of cathode a stable insertion gain of a few db may be realized. Other requirements on bandwidth, power and distortion are satisfactorily met. Thus, these tubes are potentially useful in coordinate type switches in which voice frequency signals must be rapidly switched.

The Effect of Current and Pressure on the Impedance of Cold Cathode Glow Discharge Tubes†

“…Tills relationship has already been found by Townsend and Depp (1953) at constant pressure. They also found that the resistance could be given by .Plot of reactance at 3 kc/s against the reciprocal of thc current.…”

“…It ha~been suggested that the resistive component R],l is a function of the reciprocal of the pressure. Townsend and Depp (1953) whereas Benson and Bental (1955) found that the impedance of certain commercial tubes was given by…”

On the V ‐ I Characteristic of the Double‐Cathode Discharge in a Longitudinal Magnetic Field

“…The existence of a region of negative differential resistance in the V -I characteristics of the double cathode cold discharge was already pointed out in the paper [13], while other works [l-l, 1.51 investigated this characteristic for a plane-parallel geometry in relation with the processes of cathode sputtering. The dotted lines represent the characteristics, as they would be 'expected for a usual abnormal discharge, without the double-cathode effect.…”

Range and similarity of hollow cathode discharge in argon

“…The transition is accompanied by a marked increase in the discharge current for a given voltage. This phenomenon was first observed by Townsend in 1953 [1] and later was called 'hollow cathode effect' or 'hollow cathode mode' (HCM) [2]. Although HCM has been found for >60 years, many investigations on HCD are still performed [3][4][5][6][7][8][9][10][11][12][13].…”