Abstract: A circuit configuration for measuring resistance and/or leakage between two nodes, which includes a current source for feeding a test current into one of the two nodes and a circuit element that detects the voltage resulting between the two nodes. The output of a broadband signal generator is connected to a control input of the current source. The outputs of the circuit element and of the signal generator are connected to the inputs of the correlator for determining the correlation between their output signals.

Abstract: A method detects at least one property, such as cable length, of a multiconductor cable linked to a module by way of a logic and evaluation circuit within the module. The cable has at least one supply conductor connected by the module to a first potential and at least one signal conductor connected by the module to a second potential via a pull resistor. The supply conductor and the signal conductor will or will not be interconnected at the ends of the cable depending on whether given properties of the cable are present or not. The logic and evaluation circuit module detects the potential applied to the signal conductors and thereby determines the presence or absence of the cable properties to be determined.

Abstract: An apparatus for detecting a trouble location in a wire harness can easily detect a location of any trouble such as breakage or short circuit in electric wires in a wire harness and in particular can detect the trouble location by way of a simple structure utilizing a portion with a shield function. In the detecting apparatus, a pulse signal is transmitted in electric wires (2) in a wire harness (1), in which a trouble location is to be detected, and in a sensing line juxtaposed along the electric wires (2) at their ends. A measuring device (20) receives a reflected wave from a transmitted wave and measures a difference in time between the transmitted wave and the reflected wave. A distance from a transmitting end point to a trouble location point is determined in accordance with the difference in time and a signal propagation velocity. Each electric wire (2) in the wire harness (1) is a single wire having no splice portion and a shielded wire having a conductive shield sheath (10).

Abstract: The fluid conductivity sensor disclosed herein is adapted for the non-contacting measurement of fluid conductivity and utilizes first and second insulating tubes, each of which is provided with both the driving transformer and the sensing transformer. The sensor is immersed in the fluid to be tested so that the tubes fill with the fluid. The driving transformer's are oppositely poled so that the current induced in one tube tends to return through the other tube. Shrouds are provided which link the corresponding ends of the tubes and operate to obstruct in-fluid current flow not linking both of the tubes. Accordingly the influence of objects nearby in the fluid is substantially eliminated.

Abstract: Time Domain Reflectometry ("TDR") methods and apparatus for measuring propagation velocities of RF pulses to determine material liquid contents, moisture profiles, material levels and dielectric constants including: i) TDR probes and/or probe adaptors, including series averaging probes and multi-segment probes, all employing remotely operable, normally open, variable impedance devices such as diodes; ii) bias insertion and switching networks for rendering selected normally open variable impedance devices conductive one at a time to establish precise unambiguous timing markers T.sub.1 . . . T.sub.

Abstract: This invention relates to sinewave frequency measuring apparatus and method and more particularly such apparatus including a frequency estimator triggered by a zero crossing of a sinewave and means for producing sample signals at a constant rate; and a method which provides and uses an approximation of the sinewave through the zero crossing, as a straight line between two sampling periods. Errors are eliminated by means of a low pass filter. The method performs a fractional cycle correction by adding or substracting the interpolation results from the raw period time counts.

Abstract: A signal conditioner for generation of excitation signals and for detecting an output signal from a capacitive transducer such as a strain gage, a pressure transducer or an accelerometer. The signal conditioner includes a digital waveform generator for generating a waveform that approximates a sine wave and for generating a binary signal synchronized to the waveform, a filter responsive to the waveform for providing a first sinusoidal excitation signal, an analog inverter responsive to the first excitation signal for providing a second sinusoidal excitation signal that is 180.degree. out of phase with the first excitation signal and a demodulator responsive to the binary signal for synchronously detecting an output signal from the capacitive transducer.