Abstract: An ultrasonic RFI source locator implements signal analysis to discriminate ultrasonic shocks emanating from power line equipment sources from ambient and other interference sources, as well as distinguish between specific type interference sources, such as corona and sparking discharge. The locator has a directional or contact ultrasonic sensor for receiving a signal representing the ultrasonic shocks from a targeted source, and includes signal processing circuitry to detect and compare the strengths of portions of the sensed signal that are modulated at whole integer multiples (harmonics) of an electrical power frequency (e.g., at 60 Hz and 120 Hz on a 60 Hz A/C power system, or 50 Hz and 100 Hz on a 50 Hz A/C power system) with each other, with the total signal and with selected non harmonic frequencies. The locator provides an operator indication of the result of this spectral analysis.

Abstract: A method for determining operational characteristics of capacitive sensors adapted for self-calibration includes the steps of providing at least one capacitive sensor having a suspended element and a pick-up plate. An AC input signal is applied to one of the plates, while force is provided between the plates, the force capable of variation. At least one operational characteristic of capacitive sensors can be determined, such as the suspended element spring constant and the gap distance between the plates. A capacitive sensor system adapted for self-calibration includes at least one capacitive sensor having a suspended element and a pick-up plate, a self-testing and calibration network, and a structure for generating force between the plates, the force capable of variation.

Abstract: The electronic ignition device includes an ignition coil with a primary winding terminal and a secondary winding terminal generating a spark, a power element arranged between the primary winding terminal and ground, a protection circuit issuing a disable signal to the control terminal of the power element in preset conditions, and a voltage limiting circuit having inputs connected to the primary winding terminal and to the battery voltage, and an output connected to the control terminal of the power element. The voltage limiting circuit detects a potential difference between its own inputs and supplies to the control terminal an activation signal for the power element, in presence of the deactivation signal and when the potential difference exceeds the supply voltage by a preset value. Thereby, the voltage limiting circuit limits the voltage on the primary winding terminal to a preset value which depends upon the value of the battery voltage.

Abstract: An apparatus for detecting shaking of stroke of a linear compressor and a method are provided. A linear compressor mis-operates due to change in an external voltage or noise because the shaking of the stroke is detected by the amounts of change in the stroke or current.

Abstract: The present invention relates to a high speed sample and hold circuit having a plurality of sample and hold subcircuits coupled in parallel between an input and an output. The circuit also having a calibration sample and hold subcircuit coupled to the plurality of sample and hold subcircuits. The calibration circuit is operable to modify a timing for one or more of the plurality of sample and hold subcircuits to thereby reduce sampling mismatch between the plurality of sample and hold subcircuits. The present invention also having a method of reducing timing mismatch in a high speed, parallel coupled sample and hold circuit.

Abstract: The invention is a multipath meter that analyses estimates of parameters associated with a direct signal component and one or more multipath signal components of a signal received by an antenna. The meter analyses the parameter estimates in order to facilitate the select of a location for an antenna, monitor signal quality at an existing antenna site, and/or to determine if satellite failure or some other type of signal failure has occurred. The multipath meter makes available to a user or for analysis information related to the contributions of the direct signal and the multipath signals to the received signal. The information includes estimates of various parameters such as delay, relative amplitude and phase of the direct and multipath signals. The meter calculates a ratio of the amplitudes of the direct and the multipath signals, to determine the severity of the multipath signals and, thus, the signal quality.

Abstract: A line tracer is disclosed comprising a transmitter for generating a signal in a target pipe, a cable set, a detector for amplifying the signal and filtering unwanted electronic noise, and a method for employing the line tracer. The transmitter further comprises a transmitter circuit board having a pulse generation circuit, a tone generation circuit and a transformer drive circuit. The transmitter circuit board is tuned to provide a pulse frequency of approximately 1.3 Hz and a tone rate of approximately 600 Hz. The detector further comprises a detector circuit board having a difference amplifier, a first high pass filter, a second high pass filter, a non-inverting amplifier, and a sensitivity meter. The detector circuit board is designed to amplify the detected signal and to achieve an attenuation of frequencies from 0 Hz to 400 Hz that is 80 dB/decade. The detector provides a visual indicator of signal strength.

Abstract: A plasma density measuring method which includes producing a surface wave at an interface between a dielectric member and a plasma, and measuring at least one of a plasma density and a relative change in plasma density, on the basis of the surface wave. A plasma processing system including a container having a window, and for storing therein a gas introduced thereinto, a dielectric member for closing the window of the container, a plasma voltage source for applying a high frequency voltage through the dielectric member to produce a plasma by use of the gas inside the container, wherein a predetermined process is performed by use of the thus produced plasma, a detecting system for detecting an electric field intensity distribution of a surface wave propagated through the dielectric member, and a feedback system for feeding back the result of detection by the detecting system, to determine a processing condition for the process.

Abstract: The present invention is a power monitoring circuit for sensing line conditions in a three phase power line. In the circuit a plurality of series connected power supplies for powering various components of the circuit are connected in series with a current sensing element for sensing current supplied to the power supplies. The power supply and current sensing element arrangement, in turn, is connected across a three phase bridge rectifier, which is in communication with the three phase power supply line. A circuit analyzer in communication with the current sensing element senses unbalanced line conditions based at least in part on a signal developed by the current sensing element. Preferably, the circuit further includes a three voltage reducing resistors interposed between the three phase power line and the bridge rectifier for reducing the voltage stresses encountered by the circuit's components.

Abstract: An electrical run test instrument having a connection to a device under test includes a line voltage input, a high voltage input, and a high voltage switching matrix that enables selective connections between the device under test and line voltage or high voltage inputs using the same test set-up. The high voltage input may be interconnected with a safety compliance test instrument, permitting both run tests and line tests to be performed in succession using the same basic connection to the device under test.

Abstract: There is provided a small, high-performance electrostatic capacitance probe device and a displacement measuring circuit using the probe device. The electrostatic capacitance probe device is formed from a processed, stacked substrate with a silicon substrate/insulator/silicon substrate structure. A support substrate (1) is formed through a process of etching the first silicon substrate to remove undesired portions. A probe (2) is formed by etching the second silicon substrate and provided with a proximal electrode portion (2b) secured on the support substrate (1) by means of the insulator (11) and a beam portion (2a) separated from the support substrate (1) by removing the insulator (11) from beneath the beam portion (2a). A pair of detecting electrodes (3, 4) is formed by etching the second silicon substrate, secured on the support substrate (1) by the insulator (1) and located to sandwich a portion of the beam portion (2a) close to the proximal electrode portion (2b).

Abstract: A voltage sensing apparatus includes an output for a voltage tap point that is useful in representing the voltage on a conductor that passes through the voltage sensing apparatus. The voltage sensing apparatus also performs the function of a separable insulated conductor, e.g. a conventional bushing or bushing insert as utilized in the electrical power distribution field. The voltage sensing apparatus includes a molded body having an embedded capacitance screen that provides the output. The body is molded about the capacitance screen. An arrangement is provided for locating the capacitance screen within the molded body. In a preferred embodiment, the capacitance screen is molded from a conductive plastic preferably formed with an open mesh or screen structure that permits the free flow of molding material.

Abstract: A capacitance gauge for measuring changes in the thickness of dielectric film, such as plastic film, is automatically calibrated by utilizing a direct-measurement sensor method or a contact-type sensor method alongside the capacitance sensor assembly. The direct-measurement sensor and the capacitance sensor measure the same point on the film sample, and the capacitive calibration reading is correlated to the direct-measurement sensor reading to automatically calibrate the capacitive sensor. An improved film transport assembly for serially examining plastic film material which eliminates errors in thickness measurement location and eliminates variation in distance between individual sensor readings, while at the same time allowing accurate positioning of the film in the sensors.

Abstract: Locating a fault of a transmission line in a system which performs bidirectional optical communication between a station-side device and plural subscriber devices and in which a transmission line 1 extending from the station-side device is branched by a branching/coupling device into plural transmission lines 2 each connected to the subscriber devices. The present invention provides a supervisory unit to the transmission line 1 and attenuators to respective transmission lines 2. The supervisory unit emits an optical test signal, observes a reflected signal of the test signal while changing the attenuation of the attenuators and locates the fault based on a return time and a return loss when the test signal returns as a reflected signal.

Abstract: A method for determining the DC current flowing through an AC power meter. The internal impedance of the distribution transformer is first sensed, then the DC voltage in the AC voltage waveform is measured and finally the measured DC voltage is converted to DC current.

Abstract: A sensor cable (10) for detecting and/or locating a deformation of the cable includes a conductive core (20), a dielectric layer (40), a controlled resistive layer (50), a piezoresistive layer (60), and an outer shield (70). Deformation of the cable (10) creates a change in resistance between the shield (70) and the controlled resistive layer (50), and also creates a piezoelectric-induced voltage between the conductive core (20) and the controlled resistive layer (50). The incidence and/or location of a deformation of the cable is deducible from electrical parameters, indicative of the change in resistance and the induced voltage, measured at one or both ends of the sensor cable.

Abstract: Disclosed is a semiconductor device capable of stabilizing a gate voltage at high voltage and high current, protecting the device from breakdown by preventing current nonuniformity and oscillations and the like, thereby improving reliability, and a method for controlling the semiconductor device.

Abstract: A diagnostic test system having a portable testing device for motor vehicles, controllers having an on-board diagnostic device being provided which control and monitor the engine control system and other systems of the vehicle, generate and store error codes, and which can be connected to an external testing device via a motor vehicle-side diagnosis/test plug. The external portable testing device is equipped with a modem and connected to a mobile telephone, a hand-held cell phone in particular, in order to perform error diagnosis and troubleshooting in such an interconnected network outside stationary repair shops.

Abstract: A generator wake-up system that transitions the voltage regulator from a low power, sleep mode to full voltage regulation mode when the wake-up system detects and confirms a valid frequency of rotation of the generator. The wake-up system includes a control circuit to filter, amplify, and detect the proper threshold of an input waveform; and an assessing device that implements a control algorithm to measure and validate the input waveform.

Abstract: A cooling device detection circuit and method for detecting a cooling device in a computer system. In one embodiment, a cooling device detection circuit includes a detection stage and a power management stage. The detection stage is configured to sense an indication that the cooling device is functioning and to assert a signal if the cooling device is detected. The power management stage is configured to turn off a component cooled by the cooling device if the cooling device is not detected.