Abstract: In a crossed-coil rotating-magnet measuring instrument having an approximately cylindrical core developed as winding form, a first and second coil are wound crossed one above the other. The second coil is necessarily arranged over the first coil in the regin of the ends of the winding form and thus has a greater height of winding than the latter. Within the core there is also provided a rotating magnet whose pointer shaft is extended out of an extension of the core. In order to reduce the linearity error of this measuring instrument and to permit a reading over several quadrants, spacer means are provided on the core for guiding turns of the coil spaced from the extension of the core around the latter in a rectangular plane in each case.

Abstract: A method and circuit for detecting a fault condition in a voltage distribution bus which includes sensing a first voltage drop across a test resistor wired in series with the bus, sensing a second voltage drop across a second resistor wired in series with the bus and comparing the first and second voltage drops to detect a fault condition in the voltage supply connected to the bus.

Abstract: Method and apparatus for determining, at a measurement point in a faulty conductor of electrical energy, a fault parameter such as the distance between the point of measurement and such fault or the direction of such fault. As a signal of a fault current, the device utilizes a signal I.sub.pa formed by a linear combination of a signal representative of homopolar current and a signal representative of an inverse current associated with a fault. The invention is particularly applicable in the case of networks having at the point of measurement an insensitivity to homopolar current or to inverse current.

Abstract: An instrument for measuring the moisture content of solids has probes which are placed in contact with a material undergoing moisture determination in order to measure the electrical resistance of the material. A d.c. voltage source is connected with the probes and generates the voltage required for measurement of the electrical resistance. The characteristic line representing the electrical resistance of the material as a function of its moisture content is logarithmic in nature and, in order to generate a straight characteristic line, the signals from the probes are fed to a logarithmic amplifier. The amplified signals are converted to a moisture content which may be read from an indicator constituting part of the instrument. A calibrating unit is interposed between the logarithmic amplifier and the indicator and functions to adjust the characteristic line of the instrument so that this at least approximates the characteristic line of the material undergoing moisture determination.

Abstract: A meter junction box for enabling the safe, accurate and efficient measuring of components of multi-phase electric power includes two separate spaced enclosure housings. The two housings are interconnected by a plurality of electrically conductive, non-magnetic conduits which are environmentally sealed at each end thereof in a manner to secure the interior of each housing from the adverse effects of the environment. A single, insulating jacketed electrical conductor passes through each of the respective conduits from one of the housings to the other. The individual conduits provide a means whereby a hook-on type ammeter may be functionally and individually connected with the conduits to measure the current in the conductor passing therethrough.

Abstract: A method and an apparatus for detection of knots in lumber by means of microwave radiation. Radiation from a transmitter is directed toward a piece of lumber and the radiation reflected from and/or passed through the piece of lumber is detected by means of a receiver. A radiation field having a TEM wave mode is established on the surface of the piece of lumber by means of a transmitter, whereby a radiation field which includes a TM wave mode component is generated in a knot in the piece of lumber and this is detected by means of a receiver.

Abstract: Disclosed is an electrical testing device which comprises a plurality of measuring terminal pairs and circuit means connected to the measuring terminal pairs for measuring a respective electrical parameter by means of each of the terminal pairs, the electrical circuit means operating differently depending on which of the measuring terminal pairs is used for a measurement; and indicator means connected to the circuit means for indicating the result of a measurement using one of the measuring terminal pairs.

Abstract: Shown is an apparatus and method of use where microwaves transmitted through volatiles include water vapor driven from an adequate polymer sample by heating in a closed test cell. A pump moves a predried gas and those volatiles at pressure and flow rate to a microwave transducer including a pair of antennae horns aimed at one another, one with a microwave transmitter oscillator and the other with a receiver detector. The volatiles are brought transversely across the open end of the oscillator antenna horn by a conduit. The particular orientation of the conduit is important to the accuracy of the measurement. A moisture absorbent material inserted axially into the conduit restrains the flow of volatiles changing same to liquid form. Loss of microwave energy due to the water vapors in the volatiles is measured at the output of the detector. Microwave energy absorbent material surrounds the transducer.

Abstract: In an electrical power distribution system, line disturbances produce voltage and current travelling waves, or step-change signals, that are phase-shifted 90.degree. relative to each other. A simulation signal is derived from the current step-change signal and is in phase with the voltage step-change signal. The two in-phase signals are combined and compared with established limit values to determine when a fault occurs.

Abstract: A test probe for determining the logic state of a digital logic circuit, which probe utilizes threshold detectors to determine the relative voltage level of a test point, and gate circuits to enable various voltage conditions, e.g., a ground, high, low, uncommitted, or a supply voltage, or a random pulse or a pulse train, to be be monitored and the test result indicated on an LED alpha display device. The threshold detectors are selectively settable so that the probe is particularly adapted to test TTL and CMOS circuitry.

Abstract: Test circuitry is included in a PROM memory for detecting shorts between bit lines and word lines and shorts or leaks in a memory cell. The circuitry enables a selected positive voltage to be applied across all memory cells in the memory so that the existance of leaky memory cells or shorts in the memory can be detected during testing. The test circuitry has no appreciable effect on the memory during normal operation of the memory.

Abstract: The invention provides a measuring attachment connectible to a multimeter for measuring earth resistances, comprising a casing having a first group of terminals for a measurement signal and a second group of terminals for electrical connection of the attachment to a multimeter, and electric circuits housed in the casing and comprising generator means for generating an AC current of constant value but of a frequency different from that of the mains and its harmonics, said generator means having an output connected to first and second terminals of said first group of terminals, and a synchronous detector having a measurement signal input which is connected to said second terminal and to a third terminal of said first group of terminals, a control input which is connected to said generator means and an output which is connected to first and second terminals of said second group of terminals.

Abstract: An instrument for measuring the moisture content of dielectric objects has a housing which supports capacitance measuring means. The capacitance measuring means includes a circuit which is connected with a high frequency voltage source and is designed to measure changes in capacitance. The capacitance measuring means further includes an electrically conductive rod which projects from the housing and carries an active electrode at the end thereof remote from the housing. The active electrode is connected with one terminal of the circuit and is designed to generate a diverging voltage field which penetrates into an object undergoing moisture determination. The capacitance measuring means is devoid of an electrode which is capable of cooperating with the active electrode to generate signals during moisture determination. Instead, the second terminal of the circuit is connected with a metallic cover plate which forms part of the housing and constitutes a ground of the latter.

Abstract: A microwave method and apparatus for detecting the position of a piston of a pneumatic cylinder. While the piston is being moved by fluid pressure a microwave signal is applied to a cavity defined by the piston and interior of the cylinder and the reflected microwave signal is detected. The reflected microwave signal is processed to determine piston position.

Abstract: An arrangement for electrically testing microinterconnections with electric test contacts may be used given drastically-reduced dimensions of electric conductors and of the grid dimensions in printed circuitboards. The electric test contacts are selectable by way of internal switches. The test contacts can be disposed in a matrix whose grid dimension corresponds to the grid dimension of a printed circuitboard to be tested.

Abstract: A counter is provided to count an output pulse which a pulse generator generates each time a vehicle moves by a predetermined distance. A microprocessor is provided to actuate a timer in synchronism with the leading edges of the output pulse from the pulse generator. The timer is set to a constant time interval during which the speed of the vehicle is to be detected. The microprocessor calculates the speed of the vehicle from the count of the counter which count is a value during the time interval from when the timer starts to operate to when the pulse generator generates a pulse just before or after the end point of the set time interval. Thus, the speed of the vehicle can be detected with good resolution and precision.

Abstract: A device is disclosed for testing electrical circuits. More particularly, a device is disclosed which operates to give a visual indication of both continuity and a live circuit path. The device includes a hollow casing having a conductive probe mounted at one end. A ground wire is connected to the opposed end of the casing. The testing circuit of the subject invention is disposed within the casing. The testing circuit includes a first light-emitting diode (LED) connected in a manner to pass electrical current between the probe and the ground. A second LED is provided which is connected in opposite polarity. A battery is provided to power the second LED. The battery and second LED are connected in parallel with the first LED. In operation, the first LED will be illuminated when there is a live circuit, while the second LED will be illuminated if the circuit is continuous. Neither of the LED's will be illuminated if the circuit is broken.

Abstract: A device for immersing and electrically testing an insulating glove in a conductive liquid to determine if the glove is safe for electrical work. The glove is suspended beneath a platform by a pair of insulating barrier rings which clamp the glove cuff therebetween. A hollow electrode extends into the interior of the glove and is connected to a source of water for filling the glove with water. An air sensing tube surrounds the electrode and forms an air passage therebetween and is connected to an air blower and air pressure switch for detecting and deactivating the flow of water into the glove upon it reaching a predetermined level. The inner barrier ring is mounted on a manually movable tube which is telescopically mounted about the air sensing tube and electrode. The platform is movably mounted by an elevator mechanism for immersing the glove in the conductive liquid. The barrier rings reduce the electric field stress and eliminate corona effects on the glove cuff.

Abstract: A continuity detecting apparatus for testing the continuity of conductors in damaged cables, comprises at least two test cables, each having a proximal end and distal end. The distal end of each test cable is adapted to be electrically connected to a respective end of a conductor to be tested. The apparatus includes a detector adapted to provide an output signal in response to an input signal exceeding a predetermined threshold level, a device for connecting the proximal end of at least one of the cables to a signal source and the proximal end of another of the remaining cables to the detector, and an indicator responsive to the output signal for providing an indication of current flow through a conductor connected between the distal ends of the one and the other cables.

Abstract: The present invention provides a continuity tester comprising a D.C. coupled amplifier for providing a voltage to a transducer through a voltage threshold means, an A.C. attenuator for providing positive feedback to the amplifier, a first resistor connected between the input and the output of the amplifier and a second resistor connected in series with the transducer between the input and the output of the amplifier, the first and second resistors providing negative feedback to the amplifier, and means for connecting a circuit to be tested in parallel across the second resistor, whereby if the impedance of the test circuit is below a predetermined value, the amplifier becomes unstable and causes the transducer to produce a signal whose frequency is dependent on the impedance of the test circuit.