Abstract: A wide-band, high-order, programmable video filter is implemented using transimpedance-based active integrators. An input voltage which may for instance represent a composite video signal is converted to a current in a linear manner using resistors and provided to a current amplifier at low impedance virtual ground nodes. The current is multiplied by a gain factor .beta..sub.R within the current amplifier and supplied to integrating capacitors connected in a feedback configuration around a high input impedance differential amplifier to establish an integrated differential voltage output. The transimpedance-based active integrators may be interconnected to realize wide-band, high-order video filters suitable for use in accordance with CCIR 601 standards. Input voltage swings are not restricted by a transistor's limited range of linear operation or voltage swing limitations of internal nodes but rather may allowed to swing as long as the bias currents sustain input current excursions.

Abstract: A wide band, high-order, programmable video filter is implemented using transimpedance-based active integrators. An input voltage which may for instance represent a composite video signal is converted to a current in a linear manner using resistors and provided to a current amplifier at low impedance virtual ground nodes. The current is multiplied by a gain factor .beta..sub.R within the current amplifier and supplied to integrating capacitors connected in a feedback configuration around a high input impedance differential amplifier to establish an integrated differential voltage output. The transimpedance-based active integrators may be interconnected to realize wide-band, high-order video filters suitable for use in accordance with CCIR 601 standards. Input voltage swings are not restricted by a transistor's limited range of linear operation or voltage swing limitations of internal nodes but rather may allowed to swing as long as the bias currents sustain input current excursions.

Abstract: A continuous multi-component slurrying process at an oil or gas well comprises flowing at least three separate streams of different essential materials directly into a predetermined mixing unit at the oil or gas well, wherein each of the essential materials is required to obtain a predetermined defining characteristic of the slurry.

Abstract: A continuous multi-component slurrying process at an oil or gas well comprises flowing at least three separate streams of different essential materials directly into a predetermined mixing unit at the oil or gas well, wherein each of the essential materials is required to obtain a predetermined defining characteristic of the slurry.

Abstract: A matte synthesizer and method generates baseband video signal information from user inputs for selecting levels of luminance, saturation and hue. The synthesizer includes continuously variable controls for inputting user selections over respective ranges of adjustment, a processor programmed to calculate directly a plurality of discrete amplitude samples in a chroma cycle of a video signal corresponding to a periodic wave at a baseband frequency of the video signal with a DC level determined by the luminance, a peak-to-peak amplitude determined by the saturation, and a phase shift relative to a reference burst determined by the hue, and a multiplexing method operable to read out the discrete amplitude samples to an output, during each cycle of the chroma baseband frequency. The discrete amplitude samples are calculated for a vertical field of the composite video signal and displayed during the next field. The signal thus obtained is filtered and superimposed with a synchronizing signal.

Abstract: In one embodiment, the video signal generator outputs a standardized analog video signal. The signal generator includes a clock controlling a sequential address generator. The address generator activates a memory device that is, for example, a ROM. A distortion conditioned standardized digital video signal is stored in the ROM. This distortion conditioned signal has distortion correction characteristics matching an output filter. Following the ROM is a D to A converter that converts the conditioned digital video signal into a conditioned analog video signal. A simple filter follows the D to A converter. The filter introduces distortion into the signal applied at its input but since that signal already has distortion correction characteristics therein, the distortion correction characteristics of the input signal match and substantially cancel the distortion introduced into that signal by the filter. Therefore, a standardized analog video signal is produced at the output of the filter.

Abstract: A sound masking apparatus especially useful for setting background noise levels in discrete zones includes a signal source, power amplifier, programmable attenuator and remote control. The remote control is a short range radio transmitter that sends a series of pulses that are decoded to control the attenuator. The attenuator selects among discrete possible volume levels using serially-connected analog multiplexers, the multiplexer-selected lines connecting the signal to a desired part of a resistor network defining voltage dividers. The short range radio control makes a single remote controller operable to control volume levels in any zone of a multiple zone installation without direct access to the signal source, whereby the user can change volume levels in small increments to accomodate changing conditions or preferences and to slowly bring sound masking units to full volume levels.

Abstract: High fidelity combination of low-bulk bass signal reproducer with novel upper range reproducer. Bass reproducer is box whose height, width and depth are each between about 15 and about 21 inches, the bottom of the box being essentially open and fitted with spaced feet on which the box can stand on a pile rug without materially blocking the emergence of sound generated within the box, the top and all sides of the box being essentially imperforate essentially rigid walls which essentially do not transmit sound, and a woofer sound generator mounted within the box. The box can have a generally vertically extending partition that forms a generally vertically extending open-bottomed compartment between 1 and 2 inches thick connected as a duct to conduct and discharge the lowest frequency sounds generated by the woofer.