Abstract: A built-in stress circuit for an integrated circuit that has a frequency generator, at least one self-test circuit, a temperature regulator and a controller is disclosed. The frequency generator receives a reference clock and an adjusted temperature frequency from the temperature regulator and outputs the test frequencies needed for the self-test circuits. The self-test circuits, which are coupled to the frequency generator, receive the test frequencies and dissipate power as the self-test circuits are being used. The temperature regulator, which is coupled to the self-test circuits and the frequency generator, senses the power dissipated (i.e., the temperature), adjusts a temperature frequency corresponding to the temperature desired, and outputs the adjusted temperature frequency. The controller, which is coupled to the frequency generator, the self-test circuits, and the temperature regulator, provides the control data necessary for testing both electrical and thermal stress conditions.

Abstract: A cathode ray tube may utilize a focus mask color-selection structure. The focus mask structure is susceptible to localized, transient short circuit events, or breakdown events. These events may be caused by conductive particulates that become free within the cathode ray tube and provide a short circuit between first and second layers of the focus mask. The breakdown events are undesirable because they may result in cross-strand currents causing mask strand magnetization that can interfere with a video image on the screen of the cathode ray tube. A transformer rapidly senses random changes in a voltage or a current supplied to the second layer of the focus mask. A pulse waveform generator is coupled to the transformer and provides a pulse waveform responsive to the sudden change in voltage or current.

Abstract: A method of determining a parameter selected from the electrical conductivity and the volume fraction of a component in a composition comprising a plurality of components is provided. The method comprises measuring the electrical conductivity of the composition, and selecting a relationship between the conductivity of the composition and a plurality of composition parameters including, for each component, physical parameters representing the conductivity and the volume fraction of the component, said relationship being such that the components are substantially equally represented in said relationship by means of said physical parameters. The selected parameter of the component in the composition is determined by applying said relationship to the measured conductivity of the composition.

Abstract: A rapid low voltage testing apparatus for detecting sequentially a plurality of electrical components of an electrical circuitry device for at least one of a plurality of predetermined low voltage levels. The rapid low voltage testing apparatus comprises a first multi-position switch having an output for sequentially outputting one of a plurality of input voltages; and a second multi-position switch having an output for sequentially outputting one of a plurality of predetermined output voltage levels which adjusts the sensitivity of a voltage detection circuit to the one of the plurality of predetermined output voltage levels. Upon a detection of a match between the first multi-position switch output and the second multi-position switch output, an indicator notifies the operator of the testing apparatus that one of the plurality of low voltage levels has been detected.

Abstract: A sample solution contained in a sample vessel is analyzed using a positive ion detector and a negative ion detector. The positive ion detector and the negative ion detector are supplied with the sample solution from the sample vessel, while isolating the positive ion detector and the negative ion detector from one another. Accordingly, the sample solution is not supplied from the positive ion detector to the negative ion detector, and the sample solution is not supplied from the negative ion detector to the positive ion detector. The positive ion detector and negative ion detector are preferably supplied with sample solution from the sample vessel using a bidirectional valve having an input port and first and second output ports. The input port is connected to the sample vessel, the first output port is connected to the first detector, and the second output port is connected to the second detector.

Abstract: In a method for monitoring of partial discharges in an electric power transformer (1) under normal operating conditions, the magnetic field at a high-voltage bushing (2) on the power transformer is sensed with an inductive sensor (6) comprising at least one coil (6a, 6b) arranged at the bushing, and the electric field at the bushing is sensed with a capacitive sensor (5). The output signals from said sensors are supplied to a signal processing unit (3) in which each one of the output signals is filtered in a separate bandpass filter (101, 102), whereupon the filtered output signals from said sensors are multiplied by each other. An output signal (PDI) from the signal processing unit is formed in dependence on the result of said multiplication for the purpose of detecting internal partial discharges in the transformer.

Abstract: A method of testing the electrical capacity of a plurality of secondary batteries connected to a load. The battery testing method reduces the time during which the entire electrical capacity of the secondary batteries remains low. In the case of secondary batteries which are made up of a nickel cadmium battery cell, the testing method prevents a memory effect from arising in the batteries. Using the battery testing method, the secondary battery is forcibly discharged, whereby the characteristics of the battery resulting from the discharge are tested. During the test, the secondary battery to be tested is discharged when the other secondary batteries are charged to saturation. In the case of the nickel cadmium secondary batteries, the batteries are fully discharged. The electrical capacity of the secondary battery is checked by measuring the time that elapses before the secondary battery has completely discharged.

Abstract: This invention relates to an electrostatic field measuring device which incorporates the phenomena of floating electrodes. The invention has no moving parts and is based on the use of the discharge frequency of floating electrodes as a measure of electric field intensity.

Abstract: Apparatus for directly measuring the value of a component within an RF circuit (e.g., an RF matching network within a semiconductor wafer processing system). Specifically, the apparatus applies a low frequency signal (e.g., a 1 KHz) across one or more of the components within an RF circuit using a bridge circuit that is sufficiently isolated from the RF signal to accomplish accurate measurements of the component. The apparatus monitors the amplitude of the low frequency signal across the component. The amplitude of the low frequency signal is indicative of the value of the component.

Abstract: A wear indicator is incorporated on the slider of a magnetic transducer in a magnetic storage system for in operation on-the-fly detection of the state of wear of the transducer. The wear indicator involves monitoring a change in an electrical property of an electrical circuit structure as the transducer is worn by abrasion against the magnetic disk medium. In one aspect of the present invention, the resistance (or conductance) of the circuit is monitored during disk drive operations. Part of the resistance (conductance) circuit structure is mounted on the slider and it is physically worn along with the wearing of the transducer. A predetermined change in resistance (or conductance) gives an indication of the predetermined wear limit at which the transducer should be replaced prior to its actual failure. In a specific embodiment, the circuit is configured such that an open circuit (infinite resistance or zero conductance) indicates that the wear limit has been reached.

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 discharges the set current based on the discharge current and the voltage of die battery, and projecting an actual voltage of the battery based on the battery voltage determined.

Abstract: An electromagnetic compatibility (EMC) test cell has an electromagnetically screening enclosure which is rectangular in cross-section with a length and first and second pairs of opposed side walls. A first antenna array comprises a first array of conductors extending lengthwise in the enclosure distributed at positions between the first pair of side walls to produce, when energized in TEM-mode, an electric field in a first test region of the enclosure which is predominantly polarized in a direction parallel to the first pair of side walls. Second and third antenna arrays comprising respective second and third arrays of conductors extend lengthwise in the enclosure on opposite sides of the first test region.

Abstract: A current flowing through the automotive battery and the battery voltage are measured by the battery current measuring means and the battery voltage measuring means. The battery is connected to a plurality of wiring harnesses which in turn connect to a plurality of loads. Data on normal resistance values between the battery and the wiring harnesses as produced by each of the loads being activated are stored and held in the load current data holding means. When the resistance value comparison means determines that the resistance value between the battery and the wiring harnesses calculated by the resistance value calculating means does not agree with the data of normal resistance values between the battery and the wiring harnesses held by the load resistance data holding means and produced by each of the loads being activated, it is decided that abnormal currents are flowing through the wiring harnesses.

Abstract: The porosity and integrity of a nonconductive material is determined using electron beams and electronic instrumentation. The electric corona discharge from holes in the nonconductive material is detected and analyzed in order to determine the presence of viral and sub-viral sized voids or holes, as well as other material anomalies such as blisters and bubbles.

Abstract: Device for measuring soil conductivity is comprised of a frame adapted to be conveyed over a ground surface and plurality of soil engaging coulters insulated from each other and insulatively mounted to this frame. This device also includes means for passing a current between a first pair of coulters through the soil and means for measuring this current. It further comprises means for measuring the resulting voltage between a second pair of coulters. This device for measuring soil conductivity also is comprised of electrical contact members which provide consistent electrical contact from the coulter to the means for measuring current and voltage. An electrical signal received by a coulter travels to a mounting flange and then to a dust cap. The dust cap passes this electrical signal to the spindle by way of a spring-loaded plunger. This electrical signal travels from the fixed spindle to the means for measuring current and voltage.

Abstract: A method and apparatus for detecting and measuring suspended solid particles in a molten metal, even if the metal also contains liquid and/or gaseous inclusions. The method involves moving molten metal through an orifice of predetermined hydrodynamic diameter provided in an electrically non-conductive barrier. As the molten metal is moved through the orifice, a current path is established by passing a current through the orifice from electrodes positioned on opposite sides of the barrier. Changes in voltage of the current are measured as the metal is drawn through the orifice, and the number of particles suspended in said metal drawn through the orifice is detected from the voltage changes.

Abstract: A microwave test kit including a SWR bridge with one or more accompanying precision airlines for connecting between the test port of the SWR bridge and a test device. The SWR bridge includes a branch opposite its test port which includes an adapter having a connector with a center conductor support bead matching the center conductor support bead used in the precision airlines to compensate for impedance mismatch. The test kit may further include a standard 50 ohm termination and an offset termination, having an impedance other than 50 ohms, with the adapter of the SWR bridge configured to enable a user to selectively connect the standard termination to enable measurements to be made in an error averaging mode, or the offset termination to enable measurements to be made in a magnified mode.

Abstract: A system and method for continuously monitoring the shielding effectiveness f an electromagnetically shielded enclosure is disclosed including an RF transmitter positioned remote from the shielded enclosure. RF signals emitted from the remotely positioned transmitter are received by both an enclosure receiver positioned inside of the enclosure and simultaneously by a reference receiver having its antenna positioned outside of the shielded enclosure. These two received signals are mixed so as to produce IF signals which are subsequently forwarded to a synchronous detector which determines the ratio of the two signal levels by comparing their strengths. This ratio is indicative of the enclosure's electromagnetic shielding effectiveness. If the effectiveness drops below a predetermined or threshold limit, such is determined by a comparator positioned within the enclosure and an alarm may be sounded so as to indicate that the shield is failing.

Abstract: Impedance of a power system adapted for operation at a predetermined line frequency is measured by providing a test signal of frequency different from the predetermined line frequency by an increment significantly less than the predetermined line frequency to provide an impedance measurement signal representative of the impedance of the power system at the test frequency. The impedance measurement signal is processed to provide a line impedance signal representative of the power system impedance at the predetermined line frequency.

Abstract: An apparatus includes an insulated first switching element and a capacitor which are connected in series between one of positive and negative main circuit wirings connected to an ungrounded power source and a ground potential section (vehicle body); a second switching element with one terminal thereof connected to a junction point of the first switching element and the capacitor; switching element control device for selectively closing the first switching element for a predetermined time so as to charge the capacitor and for closing the second switching element so as to discharge the capacitor while the first switching element is opened; device for detecting the electric charge accumulated in the capacitor; and device for determining the insulation between the other of main circuit wirings and the ground potential section in accordance with the detected amount of charge.