Abstract: A process for providing through plated holes in a substrate by screen printing provides uniformly thick plating of the holes. One side of the substrate is screen plated while being subjected to an underpressure between 10 and 200 gr/cm.sup.2 from a chamber fed by a large volume vacuum vat. When treating the other side of the substrate, vacuum may be increased up to 2.5 times the first underpressure.

Abstract: A capsule for the controlled release of an active material, e.g. into soil, is described. The capsule comprises an insoluble tubular housing (11) containing a number of water soluble or biodegradable partition walls (13) defining one or more hermetically sealed compartments, (12) filled with the active material (14), e.g. an insecticide. When the capsule is in contact with water or an aqueous medium the partition walls (13) slowly dissolve or degrade thus releasing the active material after a predetermined delay.

Abstract: A hydraulically actuated wheel brake with a built-in control device comprising a brake piston including two pressure surfaces each of which defines a different one of two working chambers. The pressure fluid inlet is connected directly to one of the two working chambers and via a valve to the other of the two working chambers, the valve being actuatable upon attainment of a predetermined value of inlet pressure. The brake piston has a step in its outer periphery whose surface provides one of the two pressure surfaces. The piston is guided exclusively at its outer periphery in a cylindrical bore of a housing. Since only two parts are disposed concentrically in each other, there results ease of manufacture and a minor susceptibility to failure.

Abstract: A frictionally engaging device, such as a disc brake, includes a first and a second friction element which engage one another as the device is operated to reduce the extent of and/or eliminate relative movement between these elements. The first element consists of an organically bonded friction material suffering relatively more pronounced wear, and the second element is made of a metallic material, especially iron, which suffers lesser wear in operation. The extent of wear of the first element is reduced by applying a coating of a particulate material, especially such deposited by high kinetic energy impacting of the particles, on the frictional surface of the second element which cooperates with the first element. The coating advantageously contains metals, such as cobalt, chromium and/or nickel, and/or metal carbides, especially those of tungsten and chromium.

Abstract: A device for pulse modulation automatic control, where the modulation is a combined plurality of pulse components. Each pulse component is singly controlled by a respective control voltage or current, the control voltages and/or currents being fully independent from the output demodulated pulse level and from the number, per time unit, of pulses.

Abstract: A two-way ranging system in which deviations of transmit times of interrogation signals from a nominal transit time are determined at a transponder. These deviations are dependent upon the propagation conditions for interrogation and reply signals in the medium of propagation. A normally fixed delay is developed in the transponder. This fixed delay occurs between the reception of an interrogation signal and the transmission of a reply signal. This fixed delay is so shortened as to compensate for transit time deviations of the interrogation and reply signals.

Abstract: A relay is sealed with a sealing compound when the relay housing is in a closed state, thus causing an air cushion to be formed in the inside, with an afterflow of sealing compound into the interior being prevented. Following gelling or curing of the sealing compound, a vent hole is pierced into the relay housing which, if required, may be closed following degassing of the interior space of the relay.

Abstract: An antenna system which has omnidirectional coverage in azimuth and sectoral coverage in elevation. A main reflector including a reflecting surface has polar symmetry about the Z-axis. It also has a cross section in any plane containing the Z-axis which satisfies the laws of power conservation and reflection. It is determined by the desired far-field pattern and the microwave feed pattern (for example TM.sub.01) employed. Single or dual reflector systems are described. Using the system on "receive" with multiple "feeds", full azimuthal direction finding of incident radiation can be achieved.

Abstract: A power station boiler condensate water monitor employs a light-scatter cell for the detection of oil and/or particulates in the water. In order to determine background scatter levels, provision is made to alternatively pass clean water through the cell (FLUSH). The offset voltages obtained from the detector outputs when clean water is employed are compensated for differences in temperature between the boiler condensate water and the clean water before substraction from the detector outputs when boiler condensate water is employed. The monitor is capable of detecting oil levels of less than 2 parts per million.

Abstract: A stable secondary coating, for example of nylon, is applied to a primary coated optical fiber by a process including high-speed (.gtoreq.100 meters per minute) extrusion of the secondary coating material, cooling of the extruded material by quenching in cold water at a position up to four meters from the extruder crosshead, and subsequent annealing to increase the density of the extruded and quenched material.

Abstract: A magnetic field sensor is disclosed with which the direction of a magnetic field can be determined by using the planar Hall effect. An active layer of the sensor is made of a ferromagnetic amorphous metal which is magnetically isotropic. Thus, the magnetization in the active layer always has the direction of an external magnetic field. The developed planar Hall voltage is a measure of the direction of the magnetic field.

Abstract: In picture-reproducing equipment with higher scanning frequencies (e.g., flicker-free television, visual display unit), the generation of the horizontal-deflection current is separated in frequency from the generation of the operating voltages by supplying the horizontal-deflection circuit from a DC voltage source which is part of the voltage power supply providing the operating voltages. The supply circuit is preferably connected to the grounded deflection capacitor. This makes it possible to influence the picture geometry in a simple manner, particularly to perform horizontal pincushion correction.

Abstract: A connecting arrangement comprises a crimp barrel which is crimped against the outer conductor of a coaxial cable and contains a shield wire to be connected to a wrap post of a terminal strip, and a holding device which engages the cable over the edge of the terminal strip board. Two clips are integrally formed on the ends of the holding device. One of the clips clasps the outer diameter of the coaxial cable below the strip board, and the other clip surrounds the insulated inner conductor of the coaxial cable above the strip board.

Abstract: In a tangential blower having side walls near the air outlet provided with lugs projecting into the high pressure chamber.

Abstract: The spatial position of the core of an optical waveguide (1) can be observed exactly in that the optical waveguide is irradiated, in two mutually perpendicular directions, with parallel light, which thereafter passes through each time one rod lens (31, 32) and into a deflecting optical system (8, 9, 10). With the aid of this deflecting optical system it is possible to produce two side-by-side images of the optical waveguide and its core. With the aid of such an arrangement the cores of two optical waveguides to be joined, can be optically aligned with respect to each other in a simple way.

Abstract: A flexible hinge device comprises a laminar silicon body having a groove portion etched away to define a thin flexible strip joining two rigid end portions. The silicon forming the hinge is usually of a single crystal structure. Break-off supports may be provided to support the structure prior to use.

Abstract: For fabricating porous bodies from a glass starting material, particularly in connection with the fabrication of an optical waveguide preform, it is proposed to fill powdery glass starting material under a pre-compaction into a compression mold, and to compress it thereafter. When the porous body to be formed is to have a varying composition in the radial direction, as is necessary with a view to step index optical fibers or optical waveguides having a graded index of the refractive-index profile, then differently composed powdery glass starting materials are filled one at a time, in adjacent coaxial areas, into the compression mold. This is effected with respect to each of the individual areas with the aid of a screw conveyor under a continuous, adjustable pressure and at an adjustable conveying speed.

Abstract: Electrical contacts to or mechanical connections between components and provided by using a thin layer of an alloy consisting of metals and metalloids. Such a layer shows excellent adhesion to glass or semiconductor substrates.

Abstract: A transducer responsive to rotational movement comprises a support member on which a shaft is rotatably mounted. Relative movement between the member and the shaft is sensed by flexure of a strip of a piezo-resistive mateial. Typically, the strip is facribed from signle crystal silicon.