Jitter and recovery rate of a triggered spark gap with high pressure gas mixtures

Recent attention to impulse antenna phased arrays has necessitated the need to develop a reliable high voltage, high repetition rate switch that will operate with ultra low jitter. The ideal jitter of such a switch would be a small fraction of the risetime in order to synchronize the array to steer and preserve the risetime of the radiated pulse. This paper presents the impact, gases and gas mixtures have on switch performance which includes recovery rate and in particular, jitter. A 50 Ω, 1 nF pulse forming line is charged to 30 kV and provides the low inductance voltage source to test the different gases. Triggering is provided by an SOS voltage source that supplies ≫100 kV, 10 ns risetime pulses at a rep rate up to 1 kHz in burst mode. A hermetically sealed spark gap with a Kel-F lining is used to house the switch and high pressure gas. The system contains a high pressure gas mixing chamber that can mix various gases up to 2000 psi. Gases tested include dry air, H2, N2, and SF6.