Abstract: A thyristor pulse controller in which current supply to each of a plurality of d.c. loads is controlled by respective main thyristors and a single commutating capacitor common to all the main thyristors is provided, the capacitor being connected across the main thyristors to commutate them one at a time at intervals not less than the time required to forward charge the commutating capacitor from the d.c. source and to reverse the charge on the capacitor.

Abstract: A system is disclosed for detecting, locating and monitoring floating objects and other subject matter at sea on another body of water or in other location of difficult access. A floating unit contains several retroreflecting elements and is placed at a location where detection is desired. For example, rescue or monitoring can be facilitated by detecting the floating unit from the air. Detection may include air borne signal apparatus such as a scanning laser beam or ordinary light source and air borne detection apparatus for detecting and analyzing a reflected signal.

Abstract: A separately excited speed-controlled D.C. motor which has constant armature current and pulse-controlled field current has its armature connected by way of a bridge rectifier and an inductor to an A.C. source of substantially greater r.m.s. voltage than the rated supply voltage of the armature, the inductor serving to regulate the armature current. The field winding is connected to a field excitation supply and to a thyristor chopper and the mean current through the field winding controlled by the thyristor chopper thereby to control the armature torque and therefore the speed. The field winding may comprise two field coils arranged to produce opposing magnetic fields, the thyristor chopper serving to control the net magnitude and direction of the motor field. A thyristor chopper may be provided in the armature circuit to maintain a constant armature current during plugging of the motor.

Abstract: A trip free miniature thermostatic switch having a bimetallic disc located therein is responsive to temperature for localized control of an electrical circuit. A reset mechanism in said switch provides for closing of the circuit therein, but only after the temperature has returned the bimetallic disc to the switch closed position. For example, a bimetallic member may move a switch component to the open position where it is releasably retained until the temperature change has reversed and the release mechanism is positively operated.

Abstract: A dryer is disclosed, adapted for use mounted on a plastic mold, extruder or the like. A compact rectangularly shaped drying chamber hold a porous drying basket with free air space surrounding the base of the basket to provide quick drying. An air flow system includes a blower, a removable filter and a removable heater. The dryer includes a removable desiccant cartridge and means for signalling cartridge replacement.

Abstract: An extended-area filter for filtering plastic stock at high pressures has a breaker plate with an undulating surface confronting the oncoming stock which substantially doubles the available filter area. Screen packs having fixed therein the same surface configuration are supported uniformly on the undulating surface against collapse under the operating pressure.

Abstract: A dual address paging receiver is described having page memory for automatically storing a page in the mode addressed if the user does not reset the receiver within a prescribed time interval after an alert signal is started. After a page is stored it can be recalled in the mode addressed from page memory by operating the reset button.The receiver provides two different kinds of alert signals depending upon the mode in which it is addressed. The receiver also provides a unique turn-on signal.

Abstract: A paging receiver is described having page memory for automatically storing a page if the user does not reset the receiver within a prescribed time interval after an alert signal is started. After a page is stored it can be recalled from page memory by operating the reset button.

Abstract: Drainage foils are described in two parts, a first part including the drainage surface and means for mounting the foil on a support, and the second part including the land surface and the leading edge. The second part is fitted with wear-resistant material, and is removably fitted to the first part, so that the two parts can be interchanged to facilitate changing foiling angles and land surfaces in a given installation.

Abstract: An optical apparatus using a single source of white light has five independent channels each of which divides that light into three spectral components, and supplies those components individually through individual attenuators for use as a set of fifteen separate and independently-controllable light sources. Fiber optics light conductors bring light from those sources to a transform filter in a Fourier transform optical system.

Abstract: A system is disclosed for removing squeal or noise from automotive disc brake assemblies. An emulsion of a normally soft polymer together with a cellulosic thickener, an anti-freeze compound, biocide and pigment is coated onto the back side of the outboard pad assembly. When dry the outboard pad assembly is mounted on an automotive disc brake assembly.

Abstract: A continuous working chemical laser is disclosed. A primary gas such as hydrogen or deuterium is mixed with an activator for a secondary gas, and desirably with a buffer such as a noble gas. The primary gas mixture and a secondary gas such as fluorine are mixed at low temperature and subsequently a laser emitting chemical reaction is triggered. In one embodiment the gases are mixed in supersonic flow and the reaction is triggered by a shock wave. In another embodiment the reaction is triggered by external stimulation such as ultraviolet radiation or electric discharge or the like.

Abstract: A multiport phase shifter for microwave energy provides four output components of an input wave each shifted a prescribed amount in phase, in an enclosure having two plates held together by studs mounted on one of them for locating a power divider and four independent phase-shift branches, and independent diode mounts for each, and for spacing the plates the correct distance to serve as ground planes for TEM-mode lines within the enclosure. Phase trimmers at each output port serve to adjust the output phase relations to a specification without requiring any invasion of the enclosure.

Abstract: Metal-silicide-silicon Schottky barrier diodes are made by a process which yields the characteristic of low barrier height, in the region of 0.15 volt, suitable for use without dc bias as a detector at microwave frequencies. Low barrier height metals, such as palladium, platinum and hafnium are processed through heat treatment steps which reduce the barrier height below that which is typical of point contact diodes.

Abstract: Apparatus for producing a graph of a function represented by a varying analogue input signal supplied to the apparatus, comprising display means adapted to display in a graphing operation the graph of the function, calculating means adapted to receive the analogue input signal and to calculate the value of a parameter of the function, and control means operable to interrupt the operation of the display means at preselected points in the graphing operation and to cause the display means to display the value calculated by the calculating means and thereafter to resume the graphing operation.

Abstract: A thyristor pulse controller having an electromagnetically actuated shorting contactor comprising an actuating coil and an armature which moves on energization of the actuating coil to close the contactor tips and which moves on de-energization of the coil to open the contactor tips and to create an air-gap in the magnetic circuit of the coil, is provided with an interlock circuit comprising a voltage sensing circuit connected in parallel with the contactor actuating coil, the voltage sensing circuit being adapted to provide an output signal when the modulus of the voltage across the actuating coil exceeds a predetermined value which is lower than the modulus of the voltage across the coil at the instant when the contactor tips open. A unidirectional current path, which may be provided by the interlock circuit itself, is connected across the actuating coil to discipate inductive energy in the coil when the contactor opens.

Abstract: A headbox of the pressure nozzle type has a slurry distributor providing a plurality of pairs of separated slurry passages arrayed in the cross-machine direction. The passages of each pair open at their input ends to a manifold located at one side of the distributor. Within the distributor each passage turns at a sharp angle and all the passages are aligned in the machine direction at their output ends. A nozzle structure of a turbulence-generating type is shown coupled to the distributor.

Abstract: A personal paging device is housed in a case which has one dimension (length) longer than its width or thickness, and a clip is affixed to a side on a swivel between the ends of the length dimension, which allows the device to be worn on the person in a vertical or a horizontal posture. A radio receiving antenna is carried on a flexible dielectric sheet within the casing, and radio components are enclosed within that sheet. A pair of orthogonally-related antenna loops can be provided on the dielectric sheet. The swivel clip can be arranged to cooperate with these or other antennas in a circular-polarization antenna system, such that in one orientation one or the other of the antennas will be detuned.

Abstract: A linear filter network incorporating active elements, and which obeys the relation f.sub.t .varies..sqroot.G.sub.1 G.sub.2, where f.sub.t is the band-pass center frequency of the network; and G.sub.1 and G.sub.2 are the conductance values of certain network circuit elements, has its transfer function for bandpass output controlled by a group of switchable conductances (G.sub.1 G.sub.2) in a digitally-controllable switching system that reduces the number of conductances required to achieve a given number of discrete pass-bands all having the same, or constant, bandwidth. A network that is switchable among 10 or more frequencies is used in a tone-responsive paging system for response to one or more of a series of calling tones or frequencies that follow each other in equal frequency intervals or steps ".DELTA.f" chosen so that for a series of "n" steps no tone in the series is harmonically related to any of the others.

Abstract: A new scintillator composition, consisting essentially of di-m-methylphenyl-1,3,4-oxadiazole, or 2,5-di-m-tolyl-1,3,4-oxadiazole, is prepared by reacting m-toluoyl chloride with hydrazine to form di-m-toluoyl hydrazine which, in turn, is reacted with thionyl chloride to form the desired product which is dissolved in an organic solvent. The scintillator, di-m-methylphenyloxadiazole compares favorably with present commercial products, being equal to or better than diphenyloxazole in most important respects and significantly superior in scintillation pulse height and in stability. It can be produced at a fraction of the cost of today's most widely used product.