Abstract: A test apparatus for checking test objects, such as protective relays, especially voltage, current and/or frequency relays for the protection of a generator of a power supply network, comprising a first circuit for generating and converting test signals or magnitudes to be delivered to the test objects and a second circuit for pre-programming the test signals or magnitudes to be delivered to the test objects. The first circuit comprises a first test signal generating circuit for supplying the voltage relay and the current relay with voltage and current test signals, respectively, and contains a first secondary winding of a test transformer. A static potentiometer is connected in parallel with this first secondary winding. The potentiometer supplies test signals in finely stepped or graduated values to the test objects. The first circuit further comprises a second test signal generating circuit for supplying the frequency relay with frequency test magnitudes.

Abstract: Smoke is detected by a surface ionization effect on a heated wire filament disposed opposite a negative ion collector electrode. Current flow between the wire and the electrode increases in the presence of smoke. The increase is probably attributable to surface ionization of smoke particles on the heated wire.

Abstract: A paramagnetic oxygen sensor wherein a reference chamber is oscillated into and out of an air gap of a magnetic circuit by means of a piezoelectric bender bar. The oscillating reference periodically displaces the ambient gas under measurement in the air gap and causes a varying flux in the magnetic circuit which is sensed, amplified and provided as an output signal indicative of the partial pressure of oxygen of the gas mixture.

Abstract: Transducer means mounted on a moving head produce test signals which modulate an FM transmitter on the moving head. A stationary FM receiver has demodulation means including a toggle flip-flop supplied with an FM signal corresponding to the transmitted signal, preferably an IF signal. The flip-flop changes state when its input passes through a threshold level and yields a rectangular wave output, and preferably also the inversion thereof. Short pulses are produced at edges of the rectangular wave, as by differentiation. The short pulses are applied to a sawtooth generator, preferably of the constant charging current type, to produce sawtooth waves whose amplitude and duration are proportional to the periodicity of the pulses. The sawtooth waves are filtered and the output applied to apparatus for processing and indicating variations in the object being tested.

Abstract: A circuit is disclosed for driving an electronic speedometer (or tachometer) and an associated odometer of the type suitable for use in automobiles, trucks and tractors. The circuit includes a programmable divider which can be user calibrated so that a change in a system parameter, such as tire size, can be accommodated. The circuit employs a pulse generator producing timing pulses for a magnetically driven air core gauge. The timing pulses are produced in response to pulses indicative of the remote condition being sensed as, for example, wheel rotation or engine speed.

Abstract: A star wheel, typically the starter gear of an internal combustion engine is magnetically coupled to a stationary pickup, for example a coil-core or yoke combination, a Hall generator, or the like. Upon rotation of the gear, or star wheel, sequential signals will be induced in the pickup which, related to time, provide an output signal representative of speed. To determine an angular reference position, an additional magnetically responsive reference element is included in the magnetic circuit formed by the stationary pickup and the teeth of the star wheel, to additionally modify the reluctance of the pickup-star wheel magnetic circuit, and change the characteristic of the output signal, for example by a phase jump, a discrete output level jump, or the like. The reference element may be a pin of soft iron, or of the material having soft iron characteristics, a pre-magnetized pin, or the like, exposed to the yoke arms of a pickup surrounding the star wheel, or otherwise magnetically coupled to the pickup.

Abstract: Apparatus and a method therefor for counting platelets and red blood cells in a whole blood sample includes an aperture type transducer having front sheath and back sheath flows but also including various fluid resistors to maintan proper pressure differentials and which are driven from a common air supply. The whole blood sample is injected through the aperture by use of a small bore tube also driven by the common air supply.

Abstract: A rotation detecting apparatus detects the angular position of an engine by rotating from the engine an electrically conductive rotating member having a plurality of equally spaced projections and notches formed on the periphery thereof and arranging a detector to face the rotating member and detect its projections and notches. The detector incorporates a self-running blocking oscillator circuit comprising a transformer and a field-effect transistor. With the engine rotating, the oscillator circuit oscillates when one of the notches on the rotating member is opposite to the detector, whereas when one of the projections on the rotating member is opposite to the detector the oscillator circuit does not oscillate due to the eddy current loss caused in the projection. Another circuit is connected to the oscillator circuit, and this circuit generates a pulse signal whose signal level changes in synchronism with a change in the oscillation condition of the oscillator circuit.

Abstract: A test fixture for circuit cards comprising a probe board bearing electrical test probes in a fixed position with respect to the overlying test surface. A flexible sheet is supported by the probes and serves to stabilize their relative positions. The circuit card is held against the probes by vacuum force applied utilizing a thin plastic layer overlying the circuit card. The test probe utilized in the test fixture has a conductive shaft tapering to a cylindrical tip on which a conductive spring and a conductive contact cap are slidably mountable. The cap is tapered down to the tip, and the spring is designed to engage both the tapered portions of the cap and of the shaft. A twisting motion of the cap causes the spring to electrically and physically connect the cap and the shaft. The cap also an indentation for interlocking with the flexible sheet of the test fixture.

Abstract: An improvement is provided in a device for measuring the thickness of non-magnetic layers on magnetic substrates by determining the adhesion of a magnet in contact with the layer. The device comprises a housing, a scale balance carrying the magnet at one end thereof, the scale balance being mounted rotatably on an axis, a manually rotatable disk and a first spring means connected to the scale balance at one end and to the scale disk at the other end. The scale disk and first spiral spring are coaxial with the scale balance axis. The improvement comprises drive means including a second spiral spring means which has one end attached to the casing and the other end attached to the scale disk. The second spiral spring is coaxial with the scale balance axis. The spring tension of the second spiral spring means is slightly greater than that of the first spiral spring means and counteracts the first spiral spring means.

Abstract: A video device and method for analyzing golf club swings or the like includes means for detecting the golf club swing and calculating the resultant velocity of the club head. The velocity is then displayed on a display device in either a digital or analog mode. The golf club swing can then be analyzed by comparing the relative velocities during different club swings.

Abstract: A primary and a secondary of an inductive position sensor are connected by a capacitively coupling means. An output of the position sensor is connected to a level detector functioning as a failure indicator. The capacitive coupling of the primary and secondary of the inductive position sensor results in the output of the position sensor being above a minimum signal level at every position including the position at which the sensor output indicates zero or null position. When the sensor output falls below the minimum signal level, the level detector indicates failure.

Abstract: The calibration of magnetic gauges used for measuring the thickness of a layer applied to a base can be accomplished by the use of a test sheet composed of an essentially uncoated material which exerts a lesser influence on the gauge for a given thickness than the material comprising the base upon which the measured layer is applied. An uncoated test sheet of a certain thickness, when brought into contact with the pole piece of a thickness gauge, will produce a reading equivalent to that produced when the gauge measures a layer of predetermined thickness applied to the usual base material. For calibrating a gauge used to measure the thickness of a non-magnetic layer on a ferromagnetic base, the test sheet may be a material of less magnetic conductivity, permeability and/or saturation than that of the usual base material. A non-limitative example of a material suitable for use as a test sheet is pure nickel.

Abstract: Method and apparatus for testing and setting the field strength of permanent magnets in a magnetic bubble domain chip module, wherein the final molded module is formed to contain a pair of longitudinal slots which run through the module on opposite sides thereof. The module is inserted, via said slots, onto conducting members of a magnetic bubble module testing apparatus. The conducting members effectively provide one turn coils on each side of the module. Current is induced in these coils in such a way as to either add to or subtract from the bias field provided for the magnetic bubble domain chip by the permanent magnets of the module. The module is tested to determine the upper and lower operating levels of the bias field for effective operation of the chip, and the device is remagnetized to set the bias field of the module in the center, or optimal point, of the bias margin.

Abstract: A charge-flow transistor having a gapped gate electrode and a thin-film sensor material in the gap, which sensor material is sensitive to a property of the ambient environment and has a surface conductance that differs substantially from the bulk conductance thereof. The charge-flow transistor is shown as part of an instrument operable to measure said property.

Abstract: An apparatus for testing the wall thickness of a moving tube of plastics or other electrically non-conducting material being produced by an extruder, comprises an electrically conductive measurement body arranged in the moving tube, a ferromagnetic holding member which is arranged in the tube within effective range of a holding magnet located outside the tube and which has a tie connection to the measurement body to locate the measurement body axially within the effective range of a measuring sensor located outside the tube. The holding member and the measurement body may be introduced into the tube through a channel in the extruder head, shot into the tube from a forward position, or inserted through an aperture cut in the tube wall.

Abstract: An inductive transducer intended, according to the invention, for converting the displacement of mechanical objects into an electric signal, comprising primary and secondary coils with cores, connected to one of mutually moving mechanical objects. The coils are arranged one opposite the other with a gap, wherein a main screen connected to the other moving object and at least one auxiliary screen are located. The auxiliary screen is set movably in a plane parallel to the main screen. The inductive transducer of this invention permits obtaining a functional relationship between the output signal and two or more displacements of mechanical objects, and thereby enables the relationship, including the slope thereof, to be controlled by simple means.

Abstract: A method and apparatus for setting the relative magnetic relationship between a Hall Effect switch with a given operating field strength and a permanent magnet to operate the switch and having a magnetic field with a field strength greater than the operating field strength. This invention can be used for adjusting the toggle point of a combined Hall Effect switch and magnet or the dwell between the operate point and release point of the switch. This method or apparatus comprises the steps of determining the actual switching point or dwell of a combined Hall Effect switch and operating magnet, which switching point or dwell is controlled by the combination of the field strength of the magnet and the operating field strength of the switch, determining the difference between the actual switching point or dwell and a desired switching point or dwell and then modifying the magnetization of the permanent magnet to shift the actual switching point or dwell toward the desired switching point or dwell.

Abstract: A magnetic thickness gauge having a rotatable indicator dial which is rotated to lift a permanent magnet by means of a tension spring, from the surface being measured, is provided with an automatic brake which locks the dial in place as soon as the magnet is pulled away.

Abstract: A system and method for measuring the rotational speed of a variable speed drive shaft for a ship or the like with high accuracy over a wide range of speeds. Means associated with the shaft sense the time interval for each turn of the shaft, or fraction thereof. Such time interval is accurately measured and then converted to an r.p.m. value. Steps in the method include counting the number of cycles of an oscillating signal in binary form to measure the time interval for each turn, selecting a most significant portion of bits within the number counted, determining the positional weight of the most significant bit to obtain a scaling factor, and producing a voltage inversely proportional to the value of the selected portion of bits, which voltage is then scaled by the scaling factor.