Abstract: A set of magnetically responsive vanes are secured for rotation about their mass center of gravity in a given angular spacing. The vanes have corresponding magnetic field producing coils which are in a different angular spacing such that one coil and vane is aligned and a second coil and vane are misaligned. An electrical switch is coupled to the vanes for operation in response to rotation of the vanes. A current applied to one coil aligns its vane thereto and closes the switch. The closed switch applies a load current to a second coil whose vane is misaligned. When an overcurrent occurs, the corresponding resulting field aligns its vane and opens the switch. An off current applied to a coil can align a corresponding vane to also open the switch. The switch and actuator are dynamically balanced so that moments produced by shock and vibration do not operate the actuator vanes or switch.

Abstract: An enclosure for electronic systems provides substantially total RF isolation of separate segments of a system except for the transmission of desired signals between different segments, even though the various segments are fabricated on a common circuit board. A special multilayer circuit board configuration makes this isolation feasible. Buffer circuits connected to drive signals on and receive signals from conductors which extend between isolated compartments prevent communication of stray signals along those conductors.

Abstract: First and second counterbalanced contact elements rotate about a common axis so that shock and vibration induced loads produce negligible moments on the contact elements with respect to their axis of rotation. Springs are included and arranged for snap opening and closing of the contact elements to minimize electrical arcing during opening and closing of the contacts.

Abstract: A low-impedance connection is made from a ground plane conductor plated on a printed circuit board to conductive channels mounted on a chassis to receive and guide the circuit board to a position where a connector plug on the circuit board engages a connector socket on the chassis. Insertion/extraction cams on the circuit board operate drawbars located within the channels to cause the channels to clamp down on the circuit board only when the board is in its fully-inserted position.