Abstract: It is an object to identify a failed portion in a circuit for image processing and notify a service center of the failed portion, thereby enabling the failed circuit to be promptly replaced. Circuit portions of image processing units are constructed on separate substrates. As processing routes of an image signal which is inputted from an A/D converting unit, a route in which the image signal passes through a given circuit portion and a route in which the image signal doesn't pass therethrough are set. Data of a predetermined pattern is processed by those processing routes. The presence or absence of a failure of each circuit portion is discriminated from the processing results. The discrimination result is transmitted to an external apparatus installed in a service center.

Abstract: Electromagnetic waves are driven in the pipe to be inspected in the piping system by a transmitting antenna of a transmitter, to be propagated in the pipe; while a receiving antenna of a receiver is moved outside the pipe along the pipe, to receive leaking electromagnetic waves for inspecting elements of the piping system, and the location concerned of each element of the piping system to be inspected is detected in reference to the location of the receiving antenna where the level of electromagnetic waves received by the receiver becomes a peak. The locations to be inspected are the damaged portions such as holes formed by corrosion, cracks, etc. in the pipes, and the locations of joints, etc. It is also possible to move the transmitting antenna outside along the pipe, while arranging the receiving antenna at proper place in the pipe. Furthermore, it is also possible to move both the transmitting antenna and the receiving antenna in synchronization to effect the above inspection.

Abstract: Electromagnetic waves are driven in the pipe to be inspected in the piping system by a transmitting antenna of a transmitter, to be propagated in the pipe; while a receiving antenna of a receiver is moved outside the pipe along the pipe, to receive leaking electromagnetic waves for inspecting elements of the piping system, and the location concerned of each element of the piping system to be inspected is detected in reference to the location of the receiving antenna where the level of electromagnetic waves received by the receiver becomes a peak. The locations to be inspected are the damaged portions such as holes formed by corrosion, cracks, etc. in the pipes, and the locations of joints, etc. It is also possible to move the transmitting antenna outside along the pipe, while arranging the receiving antenna at proper place in the pipe. Furthermore, it is also possible to move both the transmitting antenna and the receiving antenna in synchronization to effect the above inspection.

Abstract: A device and method are provided for locating faults in a paired line. The fault locating device has a transmitting unit connectable to the conductors of a paired line containing the fault. The device also has a portable receiving unit to track the path of the paired line. The transmitting unit contains circuits for creating and transmitting a locator signal and a carrier signal including synchronization through the conductors toward the receiving unit. The receiving unit contains a pickup coil positioned proximal to the paired line, inducing induced locator and carrier signals in the pickup coil. The receiving unit also contains circuits for processing the induced locator and carrier signals and for producing a synchronization signal used to detect and segregate a component of the induced locator signal which is indicative of a fault. The presence or absence of the indicative component is communicated to an operator by means of an audible or visual fault indicator.

Abstract: An apparatus and method are provided for use in tracing a cable; the apparatus and method allows a cable to be identified at any point along its length. The apparatus includes a transmitter for applying a unique waveform to a cable of interest, a line terminator for forming a cable loop through which current can flow, and a detector which is capable of detecting both voltage (electric field) and current (magnetic field). The unique waveform induces both a magnetic and an electric field in specifically identifiable patterns.

Abstract: A method for detecting ground faults between a community antenna television (CATV) coaxial cable and an appliance coupled to the CATV coaxial cable for receiving CATV broadcasts is provided. A potential difference between a shield of the coaxial cable and a chassis of the appliance is determined. A fault indicator is provided, if the potential difference exceeds a predetermined threshold voltage. An apparatus for detecting ground faults between an appliance and a CATV coaxial cable is also provided. The apparatus includes a comparator. A first input of the comparator is coupled to a chassis of the appliance. A second input of the comparator is coupled to a shield of the coaxial cable. The comparator indicates a fault condition if a potential difference between the first and second inputs exceeds a predetermined threshold.

Abstract: Apparatus for detecting faults in buried conductors, a transmitter adapted to transmit electro-magnetic signals down the buried conductor; this signal is provided to increase an electro-magnetic path or corridor existing at the surface above the buried conductor. The invention also relates to a detecting means adapted to detect the electro-magnetic path or corridor, and to detect electro-magnetic patches formed in the path or corridor. These patches are located over the faults, and they are characterized by presence of an increased level of electro-magnetic energy caused by the faults. The transmitter means are adapted to transmit a composite signal comprising a carrier signal transmitted by a carrier signal means and a low frequency signal transmitted by a low frequency means. The carrier signal means comprise an RF carrier signal means and an audio tone signal means; the audio tone signal means are adapted to modulate signals transmitted by the RF carrier signal means.

Abstract: Apparatus for identifying faults within electrical power cables is provided. The apparatus allows a user to detect faults in cables regardless of the cable environment's noise content. Circuitry may be included for filtering the received test signal based on an understanding of a generic urban noise environment. The apparatus can provide the user with the size and direction of the test signal at a particular testing location.

Abstract: An apparatus for diagnosing the presence and location of faults within a vehicle's electrical system includes a signal generator for generating an a.c. test signal; a switching circuit connected to an interface between the system's ECU and the system's components for selectively and sequentially applying the a.c. test signal into each electrical lead therein; and a first detector connected to the system's common ground for detecting the system's response to the applied signals, thereby obtaining a set of transitory characteristics for the vehicle's electrical system.

Abstract: A simple method and apparatus for detecting short circuits between a first circuit (77) and a second circuit (76) of a printed wiring board or printed wiring assembly by using a voltage source (10) and a sensitive logamp voltmeter (11). The voltage source (10) impresses a voltage potential between the first (77) and second circuit (76). The single voltmeter probe (39) passes along the circuit having the positive potential. The signal from the probe (39) is filtered and passed through a variable gain amplification circuit. The result is displayed on a sensitive ammeter (65). The short circuit is detected at the point on the circuit where the meter displays the minimum voltage with respect to the impressed potential.

Abstract: A PN modulated signal is applied to a near end of a buried electrical cable. The signal produces an initial pulse, a second pulse of energy reflected from a fault and a third pulse representative of the far end of the cable. The time/distance between the second and third pulses is stored. As the PN signal is continuously applied an operator, using an antenna coupled monitor, walks along the cable noting the time/distance between the initial and third pulses. When this time/distance equals the stored time/distance the operator is standing over the fault. If the fault is a high resistance fault a high voltage pulse is applied to the near end of the cable. The PN signal is initially sensed at a time when the fault has a low resistance because of arcing due to the high voltage pulse. To reduce stress on the cable, the arc is initialized by a high voltage low current signal and is maintained by a low voltage high current signal.

Abstract: A portable detector device for detecting partial electrical discharge in live voltage distribution cables and/or equipment. The device comprises a probe secured to an insulated portable handle for manual displacement of the probe. A detector device is connected to the probe for detecting a signal in the range of 5 to 10 MHz emitted by the partial discharge. The detector has an input attenuator circuit which is connected to the probe to lower the level of the detected signal to a desired level. A transformation circuit is further provided to change the detected signal to a predetermined frequency signal substantially free of noise and representative of the magnitude of the detected partial discharge signal. An amplifier circuit amplifies the predetermined frequency signal and an output circuit generates signals indicative of the presence and magnitude of the partial discharge.

Abstract: Apparatus for the detection of ground leakage in a normally ungrounded DC system includes a DC power supply and conductors from the supply for supplying power to a load connected to the DC system. There is an indicator connected between the DC system and a ground point such that a ground leakage in the system closes a circuit to activate the indicator. With such activation, a pulser periodically interrupts the circuit to effectively generate an interrupted ground fault signal. Such signal is detected by a sensor located relative to the DC system such that an interrupted ground signal detected by the sensor locates the ground fault. Noise introduced into the pulse signal by the periodic interruption of the circuit during the ground fault occurrence is suppressed by the sensor means.

Abstract: A ground fault detector and locator for use in servicing ungrounded d-c or a-c power distribution systems. A pulsating ground current is introduced between the unfaulted side of the distribution system and earth ground. A current probe and associated sensing circuits are then employed to identify the faulted branch circuit without interrupting service to unfaulted branch circuits.

Abstract: A method for nondestructively electronically detecting a short circuit in a conductor system which is composed of two parallel inductor groups connected together to form a selected current path when no short circuit exists, by the steps of: disposing a current probe at a selected location of the current path for sensing changes in the current flowing in the path at the selected location; and injecting a fast rate-of-rise current pulse into the path; and monitoring the response of the current probe to provide an indication of the existence of a short circuit.

Abstract: An electrical detection system for locating a position of interest in a medium which is electrically conductive includes a signal generator, a source, a sink and at least two probes. The probes are disposed in the medium equidistantly spaced from either the sink or the source. A signal generated by the generator flow from the sink and to the source and will also flow to the probes. The probes are connected to input terminals of a comparator to thereby compare the signal strengths at the probes. The probes are movable to different positions in the medium to determine a cross-over position such that, at the cross-over position, the perpendicular bi-sector of the line joining the probes indicates the point of interest by pointing in the general direction thereof.

Abstract: Apparatus for the detection of leakage current in a system includes a power supply and conductors from the supply for supplying power to a load connected to the system. There is an interrupter connected in the system and to a ground point such that a ground leakage current in the system has a closed circuit. Activation of the interrupter about every 12 seconds effectively generates a pulse interrupted ground fault signal. Such signal is detected by a magnetic sensor located relative to a multi-feeder system with high capacitive reactance. The sensor is immune to random electromagnetic and electrostatic conditions in the distribution system. The sensor is synchronized to operate with the interrupter so that sensing is effected at a steady level of a square wave interrupted pulse.

Abstract: An acoustic detection method and apparatus includes a source of high voltage pulses to be applied to an underground cable suspected of having a ground fault. As the pulses encounter the fault, acoustic energy is generated which may be sensed by a pair of transducers located along the path of the cable. The transducers are connected to signal processing circuitry which provides a display signal indicating which of the two transducers lies closer to the fault. The transducers are moved along the path of the cable in the direction indicated and the test is repeated until the fault is indicated as lying in the opposite direction. Thereafter the transducer are moved in the opposite direction in a shorter increment. This procedure is repeated until the direction to the fault changes each time the transducers are moved. The fault then lies midway between the midpoints of each of the two final transducer positions.

Abstract: A directional potential analyzer method and apparatus using a non-intrusive electrical measurement technique to obtain a precise location of a leak in a geomembrane liner. The method and apparatus can be used for detecting leaks in either a single layer or a two layer geomembrane liner. The directional potential analyzer comprises a differential voltage detection probe which is moved through the liquid with the potential difference between the electrodes on the probe being measured and recorded as a function of azimuthal position of the probe. An initial scan of the liquid impoundment is used as a reference trace showing all of the anomalies of an unfaulted liner. Subsequent traces obtained by rotating the analyzer probe at a later date are processed and compared with the reference trace to determine the occurrence of new anomalies representing leaks in the liner.

Abstract: A method and apparatus for locating an incipient fault at a point along the length of an insulated power line includes the application of an excitation voltage at an open end of the power line, and the signal pulse transmitted along the power line to the open end is passed through a high pass filter to remove the portion of the signal which is at a frequency below the excitation voltage and its harmonics. The filtered signal is amplified and passed through a band pass filter to remove a high frequency portion of the signal containing a large proportion of noise relative to the frequency of the partial discharge frequency from the incipient fault. This filtered signal is passed to a digital storage device adapted to be triggered by a signal of a predetermined amplitude, and the triggered digital storage device receives the amplified signal directly from the amplifier and stores digital data concerning amplitude and time for the peaks of the amplified signal for a predetermined period of time.