Low jitter, low inductance solid dielectric switches.
It has been shown that the use of graded solid dielectric sandwiches in laser-triggered spark gaps (LTS) can lead to highly desirable multichannel operations while maintaining the low delay and jitter performance characteristics of LTS. As many as ten separate breakdown channels were observed when small circular or hexagonal aluminum inserts were inserted between two Mylar dielectric sheets stressed at 4.1 kV/mil. A reduction in rise time was noted for these multichannel switching events.
Design and test of a low jitter metal to metal contact solid dielectric switch
A low jitter metal to metal contact solid dielectric switch was designed and tested. A metal to metal contact solid dielectric switch with a jitter of less than 25 ns is required for the 150 kJ experiment. Since this is one fourth the 100 ns jitter reported using exploding bridge foil (EBF) triggers, experiments to optimize this trigger were performed. A jitter of 25 ns was achieved using the EBF trigger and it was also achieved using a new type of trigger called the magnetic push trigger. This trigger uses the magnetic force between the two plates of a parallel plate transmission line to push the dielectric. It was found to be better than the EBF trigger because it was easier to design, easier to implement and did less damage to switch components.
Geomagnetic micropulsations due to the motion of ocean waves
When sea waves move in the magnetic field of the earth, electric currents are generated in the water volume. These currents give rise to a small magnetic field which perturbs the earth's field. For plane trochoidal waves, this perturbing field decays exponentially with altitude and lies in a vertical plane which is oriented in the direction of wave propagation. The magnitude of the perturbing field also depends upon the magnitude and dip angle of the earth's field, and upon the height, wavelength, and propagation direction of the sea waves. For north-south waves, sea state 5, and an altitude of 100 feet, the perturbation is of the order of 0.1 gamma.