Abstract: Rack-mount chassis for mounting to an electronic equipment rack are disclosed. A rack-mount chassis may include a housing comprising a top portion, a bottom portion, a first side portion, a second side portion and a back portion. The rack-mount chassis may further include a front portion forming a front face of the housing. The rack-mount chassis may also include at least one electronic component within the housing. The rack-mount chassis may further include at least one electrical power coupler mounted to at least one recessed portion of the first side portion of the housing configured to mate with a corresponding connector plug of a power cord and supply electrical power therefrom to the at least one electronic component.

Abstract: A handheld fieldmeter is implemented with an automatic function to drive the voltage on an output node of signal processing circuitry to circuit ground while a sensing electrode is disposed in a static-free environment. In response to a binary signal indicating whether the output node voltage is above or below ground, a microprocessor repeatedly increments/decrements a stored auto-zero multibit number, and generates successive PWM pulse streams of differing duty cycles determined by the incremented/decremented auto-zero number. The successive PWM pulse streams are integrated to ultimately produce fine zero adjustment current used by the signal processing circuitry to drive the output node voltage essentially to circuit ground. The fieldmeter also includes a pair of LEDs relatively positioned with the sensing electrode to emit light beams that intersect at the surface of a charged object when the sensing electrode is positioned a prescribed distance from the charged object.

Abstract: A device for measuring the resistivity of a conductive layer buried beneath an outer layer. The device is capacitively coupled to the buried layer by a driven electrode and a pickup electrode. An adjustable frequency source resonates the two electrodes with an inductor so that an attached meter measures the resistivity of only the buried layer.

Abstract: A non-contacting voltage metering device for monitoring the electrical potential of a test surface includes a sensing integrator, and a tuning fork mechanism for modulating the capacitive coupling. The integrator input is coupled to the amplifier output and the integrator output is connected to a high-voltage FET output amplifier. The apparatus includes a feedback circuit with a phase sensitive detector which has an input coupled to the integrator output and an output coupled to the integrator input, and a reference terminal coupled to the modulating mechanism for receiving the predetermined frequency.

Abstract: A voltage amplifier for amplifying an input voltage signal is disclosed. The amplifier includes a string of MOSFET circuits coupled between a voltage-to-current converter and a high voltage power supply terminal. The string of MOSFET circuits may be expanded to achieve linear voltage amplification over a wide voltage range.

Abstract: A circuit for providing DC bootstrapping to an AC amplifier integrates a sample of the output of the amplifier and feeds the result of that integration to the input of the amplifier, thereby driving the input of the amplifier to a zero potential level. The integration can be accomplished by an operator amplifier and a capacitor in a feedback circuit.

Abstract: A multilayer tape probe for measuring the movement of charge has at least a pickup electrode comprising one layer of electrically conductive tape and a shield electrode comprising another layer of electrically conductive tape, the pickup and shield electrodes being separated by a dielectric strip. Circuitry is connected to the probe to drive the shield electrode and to monitor the potential difference between ground and pickup electrodes and actuate an alarm if an unwanted charge is present.