Abstract: An apparatus for detecting a connection between adjacent vertical panels having a first contact element positioned adjacent a bottom of one of the panels, a second contact element positioned adjacent a bottom of an adjacent panel, a first conductive line extending from the first contact element, a second conductive line extending from the second contact element, an electrical source for passing a current to at least one of the first and second conductive lines, and a detector connected to one of the first and second conductive lines for ascertaining the existence of a connection between the first contact element and the second contact element. The second contact element is positioned in proximity to the first contact element when the panels are connected together. The first contact element is affixed to a connector member of the panel. The second contact element is affixed in a channel of an adjacent panel. The connector member is a T-shaped member.

Abstract: A device fop detecting liquid incendiaries contained in bottles comprises a flexible cradle, such as a sling of thin rubber sheet (2), mounted between two supports (4); two conductors arranged laterally on the cradle (6), each conductor having a large surface area to thickness ratio; and an electrical circuit including a power source and indication means to provide an indication of the dielectric properties of a bottle placed within the cradle.

Abstract: The apparatus for measuring pulse energy includes integration means and serves to measure high-current disturbances carried by a cable. The apparatus is characterized in that it further includes a current-to-voltage converter (2) mounted on the cable (1), attenuation means (3, 4) coupling said converter to the integration means (5, 6), and a processing and storage assembly (12) coupled to the integration means and to an output display (20). Application: monitoring lightning protection equipment.

Abstract: A sensor and method for identifying the surface properties of a workpiece includes a microstrip sensor for transmitting and receiving microwave signals and surface properties determining means for determining the surface properties of the workpiece, including the type of material from which the workpiece is constructed, based upon the strength of the detected microwave signals. The surface properties identifying sensor also includes a microwave generator for producing microwave signals at a predetermined frequency for transmission by the microstrip sensor and a detector for detecting the microwave signals received by the microstrip sensor from the workpiece. Thus, workpieces comprised of a conductive material, an insulative material and a conductive material coated with a radar absorbing material can be readily distinguished by the surface properties identifying sensor and method.

Abstract: In a cell for measuring electrical conductivity, a container (2) and electrodes (1) are made of ceramics having high corrosion-resistant property. Insulating ceramics are used for the container (2), and conductive ceramics having resistance value of several k .OMEGA..cm or less is used for the electrodes (1). The ceramics are far superior to glass in corrosion resistant property and mechanical strength under normal as well as high temperature conditions. Further, the cell is produced at lower cost than the one made of precious metal and has high corrosion resistant property and can be used under strong acid or strong alkaline conditions. It has high mechanical strength and can be used under high pressure and high temperature conditions and produced at low cost because precious metal is not used for the electrodes.

Abstract: A sheet thickness measuring apparatus includes an electrostatic capacity measuring device for measuring the eletrostatic capacity of a sheet, a resistance measuring device for measuring a resistance value of the sheet, and a calculator for calculating a thickness of the sheet on the basis of the electrostatic capacity measured by the electrostatic capacity measuring device and the resistance value measured by the resistance measuring device.

Abstract: A non-contacting electrostatic measurement apparatus including a vibratory element and an electrode, affixed to the vibratory element, suitable for sensing a capacitive coupling relationship with an electrostatic field to produce a signal indicative of the magnitude of the electrostatic field. The signal is transmitted to signal processing circuitry via conductive fibers so as to impose little mechanical loading on the vibrating electrode. The electrode may be either unshielded, for an electrically floating electrostatic voltmeter, or shielded, for an electrostatic voltmeter employing electrically grounded components.

Abstract: The electrodes of an electrostatic capacitor which is used to determine the alcohol concentration in a mixture of gasoline and alcohol, are connected with a frequency oscillator of the LC type which applies a signal having a frequency which is equal to or greater than 10 MHz. The setting of the oscillation frequency to 10 MHz or more eliminates the amount of change in electrode loss and enables stable and accurate alcohol concentration determination.

Abstract: A method of monitoring ion mobility in an electro-conductive fluid, such as an electrolyte in a lead-acid battery to determine the state of charge of the battery, includes the steps of immersing a pair of test electrodes in the electro-conductive fluid, and generating a test signal having a pulsed waveform. The pulsed waveform of the test signal has a voltage which remains constant over a predetermined portion of the signal's period, that portion being selected to ensure that ion mobility in the electro-conductive fluid has reached a steady state velocity. The method further includes the steps of applying the test signal to the pair of test electrodes to cause a current to flow through the test electrodes and the electro-conductive fluid, and sensing the current flow through the test electrodes and fluid. The sensed current is indicative of ion mobility in the electro-conductive fluid.

Abstract: A testing method for connecting a first group of input conductors to output conductors in which the number of switching devices connected to each output conductor at connections with the group of input conductors are summed individually, the output conductor having the least number of switching devices at these intersections is chosen, and the switching devices are summed for each of the group of input conductors having a switching device at an intersection with the chosen output conductor and the input conductor having the least number of switching devices is selected. A switching device at the intersection of this first selected input conductor and the first selected output conductor is chosen for closure to provide the first connection in the output combination desired. The process is repeated until all of the connections are chosen or one fails.

Abstract: A method for measuring the thickness of very thin oxide layers on a silicon substrate. A corona discharge source repetitively deposits a calibrated fixed charge density on the surface of the oxide. The resultant change in oxide surface potential for each charge deposition is measured. By choosing a starting value for an assumed oxide thickness, the approximate change in silicon bandbending per corona discharge step is determined. The cumulative changes in bandbending versus oxide surface potential yields an experimental bandbending versus bias characteristic. A theoretical bandbending versus bias characteristic is established. The experimental and theoretical characteristics are matched at predetermined points thereof and then the assumed oxide thickness is iterated until both characteristics superimpose in the silicon accumulation region. The iterated oxide thickness that allows both characteristics to superimpose is the oxide thickness value being sought.

Abstract: A test pattern preparation unit divides output pins of each circuit element mounted on a printed wiring board into a group to which a logical value 0 is assignable and a group to which a logical value 1 is assignable, to thereby prepare a test pattern for detecting short-circuit failures between the groups. If short-circuit failures are undetectable among output pins in a given group, these output pins are further divided into a group to which the logical value 0 is assignable and a group to which the logical value 1 is assignable. In this way, the output pins are repeatedly divided into groups, to form test patterns for detecting short-circuit failures. These test patterns are applied to the board through a tester to detect short-circuit failures.

Abstract: This invention is a battery monitor and battery capacity indicator that uses a sense cell in addition to the main battery to determine main battery remaining capacity and depletion condition. A parameter of the sense cell is related to the main battery capacity so that the main battery will have a minimum capacity remaining when the sense cell parameter reaches a particular value or crosses a particular threshold. In a preferred embodiment, the sense cell is a battery which is identical and of the same manufacturing lot as the battery cell or cells in the main battery pack. A current is drawn from the sense cell that is larger than the current being drawn from the main battery. When the sense cell is fully depleted, the main battery will have a remaining capacity whose magnitude depends on the relationship between the main battery current and the sense cell current.

Abstract: A non-destructive test system that displays time domain amplitude returns from multi-frequency, multi-phase, constant magnitude RF signals, that are reflected by differences in characteristic impedance of a wire over ground plane transmission line. The reflections are used to detect RF discontinuities or faults in conductive areas that form the ground plane which preferably are resolved using a generalized pencil-of-points algorithm. The nondestructive testing system so constructed is especially useful in testing field repairs of radar absorbing material (RAM) and other features of a conductive object or vehicle whose radar return is to be minimized.

Abstract: A fault detection circuit for detecting leakage currents between a DC power source and chassis of an automobile, includes a voltage sensor coupled to the DC power source, the voltage sensor including an analog reference and a chassis ground. A differential amplifier is coupled to the voltage sensor and detects variations in the analog reference and the chassis ground. A voltage comparator unit determines whether the variations detected in the differential amplifier is above a predetermined threshold value. A built-in test circuit tests whether the fault detection circuit is operating correctly.

Abstract: An device for monitoring workplace air comprises a monitor cell comprising a base and a removable assembly. The removable assembly comprises (1) a flat, electrically insulating substrate having a first surface, (2) an electrolyte cell having an anode and a cathode disposed on the first surface, the anode and cathode spaced apart to define a controlled volume for holding a quantity of an electrolyte, and (3) means for applying a controlled electrical potential to the cathode. The base comprises (1) an air inlet portion for sampling air, (2) an air outlet portion connected to an air sampling pump, (3) a channel connecting the air inlet and the air outlet and adapted to introduce air to the electrolyte in the electrolyte cell, (4) a reservoir for storing the electrolyte for the electrolyte cell, and (5) a wick for supplying electrolyte from the reservoir to the electrolyte cell.

Abstract: A method for determining whether a metallic path (such as a wire) under test carrying an undetermined load current is so corroded as to require replacement applies a test current to the metallic path under test and a total current passing through the metallic path, equal to the sum of the undetermined load current and the test current, is measured. A voltage between two selected points, separated by a known length, on the metallic path is also measured. Resistance of the metallic path is then calculated by measuring an angular phase difference between the voltage and the total current, calculating an impedance of the metallic path from the values of the voltage and the total current then multiplying the impedance by the cosine of the angular phase difference. The resistance of the metallic path under test is correlated to the resistance of metallic paths of known corrosion to determine the degree of corrosion on the metallic path under test.

Abstract: An improved soil moisture sensor and circuity are described which permit a more compact, simplified, and less expensive integrated unit wherein the essential circuitry of the device is sealed within the sensor head. Determinations of resistance and capacitance are made using a coaxial or other capacitor having spikes or probes which are inserted into the soil or other material.

Abstract: An electromagnetic disturbance power (EDP) checker measures disturbance waves of an equipment under test (EUT), that is, a small electric appliance having a power cord. The EDP checker is capable of detecting and measuring disturbance waves even in sites more confined and having more external disturbance waves than in absorbing clamp method. The EDP checker includes a VHF current probe 2, a matching circuit 3 having input impedance matched at a reception frequency of a measuring equipment (receiver) 6 connected to the VHF current probe 2, and a circuit separating mains 4 for designating terminal impedance of the matching circuit 3 and eliminating influence of power source impedance. Power is supplied from the circuit separating mains 4 to drive the EUT 5 connected to the VHF current probe 2. The maximum value of disturbance power generated by the EUT 5 and supplied through the power cord 12 is measured by the measuring equipment 6 connected to the VHF current probe 2.

Abstract: A method for improving accuracy of estimating natural frequency of a distribution system. The estimation is performed in order to identify a rectifier load that generates harmonics due to commutation oscillation. It includes the steps of measuring a charging current flowing into a power factor improving capacitor to obtain first data, removing fundamental frequency from the first data to obtain second data, determining, from the second data, a first time at which the amplitude of commutating oscillation components takes a maximum value, picking up third data in the interval beginning from the first time and ending at a second time later than the first time by T/N, where T is the period of the fundamental frequency, and N is the number of rectifier phases, performing frequency analysis on the third data to form fourth data by expanding the third data into a Fourier series, and determining a local peak frequency, that is, the natural frequency in the fourth data.