Abstract: A fluid pump is shown which includes integral valve and cylinder housings. The cylinder housing is formed with axially aligned cylinders. Axially movable pistons are located in the cylinders, which pistons are interconnected by a piston rod extending through a common inner end wall of the cylinders. Axially movable push rods extend through opposite outer end walls of the cylinders. The valve housing contains a plurality of three-way valves for communication with opposite ends of the cylinders, which valves are interconnected for simultaneous movement thereof. Mechanical linkage connects the push rods to the valves for actuation of the valves from a first to a second condition when the pistons are moved to one end of the cylinders, and for actuation from the second to the first condition when the pistons are moved to the other end of the cylinders. Resilient rocker arms are included in the mechanical linkage for storing and returning kinetic energy of the movable pistons at opposite ends of piston travel.

Abstract: Microwave communication and radar systems that employ a blazed microwave reflection grating are disclosed in which the grating comprises an array of electrical conducting scattering elements having plane parallel surfaces that face in the same direction. The plane parallel faces are positioned in parallel equally-spaced planes to provide a generally stair-step, or Venetian-blind type structure. Microwave energy beamed onto the plane parallel surfaces of the array exits at a diffraction-mode angle within the reradiation pattern of the individual scattering elements of the array. Frequency steering of the exit beam in one plane of the array is provided by varying the frequency of the illuminating beam.

Abstract: A frequency selective limiter comprising a plurality of LC series-resonant filters having resonant frequencies uniformly spaced over the passband. Each filter is formed of two identical LC series-resonant sections with a diode limiter coupled between the two sections. The filters are coupled in parallel between the limiter input and the load to form two groups having alternate resonant frequencies with signals passing through one group being shifted in phase by 180.degree. relative to signals passing through the other group.