Abstract: A method is disclosed for dynamically testing a radio system having output terminals connectable to a speaker system in a motor vehicle wherein the method utilizes a dynamometer, a transverse electromagnetic cell, a signal generator and a signal analyzer and includes the steps of placing the motor vehicle in the transverse electromagnetic cell, connecting the output terminals to the signal analyzer, operating the motor vehicle on the dynamometer inside the transverse electromagnetic cell, generating a signal using the signal generator, transmitting the signal from the signal generator to the transverse electromagnetic cell, emitting the signal onto the motor vehicle, and measuring an output signal generated by the radio system at the output terminals using the signal analyzer.

Abstract: Apparatus for testing operation of a vehicle instrument panel that includes first and second electrical connectors each of predetermined connector configuration and each having a predetermined number of individually identified electrical contacts arrayed in identical series. An array of electrical switches is disposed on an operator panel, with each of the switches having a pair of switch contacts respectively connected to corresponding identically identified contacts of the first and second connectors. Each of the switches has facility on the operator panel responsive to an operator for selectively individually closing or opening each of the switches to interconnect or disconnect within the apparatus the corresponding connector contacts of the first and second connectors. A pair of single-conductor jacks are disposed on the panel adjacent to each of the switches, with each of such jacks being connected to a corresponding contact of the adjacent switch.

Abstract: A method is specified for detecting ground faults on the conductors of an electrical machine, in which method the conductors of the machine are biased with respect to ground by means of an injection voltage (Ui). An optimum utilization of the injection transformer (5) is achieved when the injection signal (Ui) comprises in the transmission period (S) a square-wave signal which switched over periodically between a positive and a negative maximum and has at the start and at the end of the transmission period (S) a quarter-period either of the positive or of the negative maximum.

Abstract: The change in thickness of a film on an underlying body such as a semiconductor substrate is monitored in situ by inducing a current in the film, and as the thickness of the film changes (either increase or decrease), the changes in the current are detected. With a conductive film, eddy currents are induced in the film by a generating an alternating electromagnetic field with a sensor which includes a capacitor and an inductor.

Abstract: A clamping mechanism for mounting a monitoring device to an electrical cable includes a core assembly formed by a plurality of laminations secured together and arranged in a generally rectangular configuration. A spring spanning the core is anchored at one end to the core at a point near the housing of the monitoring device and at the other end is attached to a bridging member affixed at the opposite end of the core near the housing. This allows the spring to expand less as it transverses the bridge in order to accommodate different power cable diameters.

Abstract: A method of frequency estimation is disclosed which uses a Fast Walsh Transform (FWT) in place of a conventional Fast Fourier Transform (FFT) technique. The inventive method is based on a linear relationship between the unknown signal frequency and the sequency of a Walsh function which corresponds to the sample of the FWT with maximum absolute value. The resulting discrete data is smoothed mathematically by a sequency interpolation process, which improves resolution and accuracy. The disclosed FWT method provides greater speed and simpler implementation than the prior FFT technique, since the FWT method follows one simple repetitive data flow pattern (additions only), while the FFT technique follows more complicated butterfly patterns (multiplications and additions).

Abstract: The invention relates to an acquisition path for acquiring a voltage pulse, and to a system and a method making use of said path, the path comprises:a path input for a pulse signal;a module for determining the polarity and for limiting acquisition of the input signal;a control module for controlling acquisition and for storing the polarized peak value of the input signal;a detect-and-hold module for detecting the polarized peak value of the signal being acquired, and for holding it; andselection means for selecting the rating of the signal being acquired;according to the invention the selection module for selecting the rating of the signal being acquired comprises a plurality of measurement ranges all of which are connected at their upstream ends to the path input, and all of which are connected at their downstream ends to automatic selection means for automatically selecting the optimum measurement range for the signal being acquired.

Abstract: The measuring device of the invention uses a capacitor polarized by a continuous voltage and conditioned by a continuous charge amplifier, this charge amplifier having a high-band filter structure, preferably of the second order. The technology of the capacitor and the linking cable is coaxial. The tuning of the chain measurement is effected theoretically without needing standardization.

Abstract: The composition of an electrically conductive mixture, preferably a mixture of gasoline and alcohol, is measured using a single measurement cell having a first electrode and a second electrode with a measurement space therebetween for receiving a specimen of the mixture. With a specimen of the mixture in the measurement space, the first electrode is alternatively connected to a reference discharge voltage, preferably ground, and to a feedback control voltage. A first operational state encompasses the period when the first electrode is connected to the reference discharge voltage and a second operational state encompasses the period when the first electrode is connected to the feedback control voltage. A first operational state peak voltage is measured during the first operational state, and a peak second operational state voltage is measured during the second operational state.

Abstract: An electron beam stop for use with high power electron beam accelerators can be used to measure beam parameters including energy, current, scan width, scan offset and scan uniformity. The beam stop is split in two segments in the direction of electron travel, with the first segment closest to the beam source absorbing a portion of the electrons incident thereon and the second segment farthest from the beam source absorbing all of the electrons that pass through the first segment. The ratio of charges deposited in the two segments is a sensitive index of the energy of the primary electrons, i.e., a measure of beam energy. The sum of the charges in the two segments is a direct measure of the number of electrons incident on the absorbing medium, i.e., a measure of the beam current.

Abstract: A combination and unitary corrosion monitor and reference cell for cathodic protection systems includes an elongated tubular metal element of the same material as the structure to be protected and a reference cell on one end of the tubular element, adapted to be buried or submerged in an electrolyte. The tubular element includes resistance connections along its length and a reference resistance element sealed inside. Ratiometric resistance measurements enable the extent of corrosion and corrosion rates to be determined with automatic compensation for temperature changes. Both the resistance measurements and the potential measurements from the cell may be taken from the same test station or location.

Abstract: In a grain harvester having apparatus for measuring the moisture content of grain by directing a radio frequency signal along a measurement signal path through the grain and determining the moisture content from the phase shift and attenuation experienced by the measurement signal, calibration apparatus is provided for calibrating the moisture measurement apparatus without interrupting the grain harvesting operation. An attenuator, calibrated to a traceable standard, is selectively inserted into the measurement signal path to produce an expected attenuation of the measurement signal. The actual attenuation resulting from the insertion of the attenuator is compared with the expected attenuation and the difference is used to derive a control voltage for controlling the gain of the measurement signal path.

Abstract: A capacitive gaging system comprising a capacitive displacement sensor and an interface circuit is used to replace a Linear Variable Differential Transducer (LVDT). An output of the capacitive displacement sensor is modified by the interface circuit which provides an output signal or signals representative of different types of LVDT outputs. The capacitive displacement sensor and the interface circuit can then be used to replace the LVDT in an LVDT measurement system. Accordingly, the capacitive displacement sensor and the interface circuit replace the LVDT without replacing the rest of the measurement system.

Abstract: A simple method for evaluating the dielectric breakdown of an oxide layer on a silicon wafer is disclosed. The SPV method is utilized to measure a diffusion length L.sub.on of minority carriers when the silicon wafer is illuminated by white light from another source and a diffusion length L.sub.off of the minority carriers when the silicon wafer is not illuminated by white light from another source. A diffusion length L.sub.safe, which is determined by trap sites in the silicon wafer, is calculated from an equation L.sub.safe =(L.sub.off.sup.-2 -L.sub.on.sup.-2).sup.-1/2. Since L.sub.safe has a strong correlation with the dielectric breakdown of the oxide layer, the dielectric breakdown of the oxide layer can be easily evaluated by L.sub.safe during the fabrication of the silicon wafer.

Abstract: A system to sense changes in the state of an ion exchange resin bed which includes first and second current electrodes spaced from each other, a first electrical circuit electrically connecting the current electrodes and designed to be connected to a source of alternating current, and also including first and second voltage probes spaced from each other and located approximately between said first and second current electrodes with a wire connecting voltage probes. A second electrical circuit consists of the first and second voltage probes, the wire and the portion of the resin bed lying between said voltage probes so that when the first electrical circuit is energized by the source of alternating current a voltage is induced in the second electrical circuit which corresponds to the state of the resin bed located between the first and second voltage probes.

Abstract: This invention is an inexpensive probe apparatus operating at high precision that can be used for both low-frequency and high-frequency measurements. A line with a first and second conductor is extended from a probe connected to a circuit component. A low-frequency or high-frequency device is alternately connected to the line. A third common conductor runs parallel to the aforementioned line and a resistor and capacitor is connected between the probe end of the aforementioned second conductor and the aforementioned common conductor.

Abstract: A battery condition detecting method is provided which includes the steps of setting a current required during standard discharge of a battery as a set current, detecting a discharge current and a voltage of the battery, determining a battery voltage when the battery discharge the set current based on the discharge current and the voltage of the battery, and projecting an actual voltage of the battery based on the battery-voltage determined.

Abstract: A test instrument (50) for testing a cable (52), the test instrument having a main unit (54) and an interchangeable performance module (56). The main unit of the test instrument contains signal generators for generating AC and DC test signals. The AC test signals are generated as single-ended signals and applied to a pair selection switching array (76). The pair selection switching array switches the single-ended test signals to a plurality of lines (84a-84d) that couple to the performance module. The performance module is an interchangeable module having a plurality of balancing networks (baluns) (102a-102d) that are connected to the plurality of lines. Single-ended test signals applied to the baluns are converted into balanced signals and applied to a cable being tested. The performance module may be interchanged to allow the main unit to be connected to cables having various impedances and connectors.

Abstract: An apparatus is provided for monitoring ignition in individual cylinders of a multi-cylinder engine of the type having an ignition system which includes a separate transformer for each cylinder. Each transformer has primary and secondary coils. The secondary coil is connected in series with a spark gap in an associated one of the cylinders. The ignition system further includes selector switches for receiving cylinder select signals and responsively connecting respective transformer primary coils. The current flows through the primary coil resulting in a voltage potential across an associated spark gap which normally increases to a magnitude sufficient to cause a spark across the spark gap. A first circuit receives the cylinder select signals, senses time delay between the reception of a cylinder select signal and sparking in a respective cylinder and responsively produces a delay signal indicative of the sensed time delay.

Abstract: The performance of a device under test is observed with and without the presence of controlled EMI fields. Voltage signals from the device under test are transmitted to an oscilloscope by overdamped conductors, a hybrid electrical/optical transmitter, a fiber optic cable, a receiver and a conductor cable. The overdamped conductors are transparent to the EMI fields and the current in those conductors is kept very small by the use of a very high input impedance in the transmitter. The hybrid transmitter may be an analog or a digital transmitter.