670. Texture of evaporated CdS films: C O Muller and H Peibst, Phys Status Solids, 8 ( 1), K51–K52

Abstract

The design and performance characteristics of a high-voltage pulse generator for use with spark chambers in space are described. In order to minimize power consumption, the pulse generator is designed around a cold-cathode thyratron. The complete pulse generator consists of a thyratron pulser and an avalanche-transistor switching circuit. Included also is a simple means for applying a steady clearing field to the spark chambers. The pulse generator can be triggered at uniform repetition rates up to about 100 per second to produce negative pulses with a peak amplitude of typically 2 kV. The observed rise-time is about 5 ns with only stray capacitance loading. It increases with the capacitance loading introduced by a spark-chamber at the output of the pulser. The total delay-time from the input trigger pulse to the output pulse is about 140 ns. The pulse decays exponentially with a time constant of the order of a microsecond. Pulse amplitudes up to 4 kV are possible with the particular thyratron selected for this application. The particular high-voltage pulse generator described in this paper provides 2100 V to three spark-chambers each with a capacitance of 150 pF. The power consumption of this generator with a single power supply is typically 0.5 W at low pulse repetition rates, 1.2 W at a pulse repetition rate of 20 per second, and 3.3 W at 100 pulses per second; alternatively, the power consumption of a pulse generator with multiple power supplies may be reduced to typically 0.1 W at low repetition rates, 0.8 W at 20 pulses per second and 2.9 W at 100 pulses per second. In laboratory tests, several krytrons have been pulsed from 275 to 385 million times before failure.