Yet, Inc.

Tut Systems, Inc.

Rolm Corporation

Tutankhamon Electronics, Inc.

Echelon Corporation

Ion Systems, Inc.

Other

Transwave

Autoseq, Inc.

Martin H Graham

Matthew Taylor

Howard W Johnson

Mark S Miller

Charles Melvin Aden

Harold H Webber

James M Kasson

Philip H Sutterlin

Charles Matthew Corbalis

Amy O Hurlbut

Michael G Duncan

Chin-Chen Lee

John D Edwards

Enoch Callaway

Kevin Braun

Melvin P Klein

David D Cudaback

Austin C Hoggatt

Rod G Sinks

Thomas J Conroy

Anthony J Ireland

Paul L Richards

John W Otvos

A method and apparatus is described for a time modulated signal. A cosine function is used as the basis for the signal with time intervals at the maximum and minimum values of the cosine function defining the encoded data. The received waveform is twice differentiated to provide a cosine function from which zero crossings are detected and the time intervals determined.

Time modulation with cosine function

A novel data transmission method and apparatus is disclosed for communicating digital data using existing telephone wiring. According to the present invention, the digital data is represented by the time interval between two consecutive biphasic pulses. Biphasic pulses are used in the present invention because each biphasic pulse does not carry any dc component so DC component in the transmission line can be eliminated. In addition, additional data can be encoded in the amplitude or pulse width of each biphasic pulse so that higher data encoding ratio can be achieved.

Biphase multiple level communications

An Op amp circuit is used to provide higher capacitance to a power network to remove unwanted high frequency components from the power signal. At the primary power line frequency, a lower capacitance is presented by the circuit.

Apparatus for reducing apparent capacitance in high frequency filter for power line

A conductive shield for surrounding a high efficiency light bulb such as a spiral fluorescent bulb is described. A conductive curtain having apertures through which light may pass is connected to the threaded grounded base of the bulb. The apertures in the curtain present high impedance to stray electrical energy (SEE) from the bulb thereby reducing SEE.

Shield and method for reducing the stray electric energy (SEE) generated by a high efficiency light bulb

A circuit and method for measuring pollution on an AC power line is described. After attenuation of the AC power signal, the remaining signal is differentiated, rectified and smoothed to provide a DC signal representative of the pollution which can be viewed on an ordinary meter.

Circuit for measurement of electrical pollution on power line

Concentrations of positive and negative ions that are generated in the ambient air at a selected location are controlled in time-varying manner. Apparatus for generating air ions includes controllable high voltage sources and electrodes connected to the sources adapted to generate positive ions and negative ions in ambient air near the electrodes. Control circuitry is coupled to the high voltage sources to control the voltage levels at the electrodes for altering the quantities of positive ions and/or negative ions that are generated in time-varying manner within the ambient air about the electrodes. The control circuitry may control the voltage sources to generate a simulated ion signature of variations in ion concentrations as detected at a selected geographic location.

Dynamic air ionizer and method

An apparatus is described for determining whether the power applied to two outlets is in phase or out of phase. Two plugs are used, one for engaging each of the outlets. A circuit coupled to both plugs includes a plurality of indicators, and in one embodiment two indicators indicate the presence of power at each of the plugs, and the third, whether the power is in phase or out of phase.

Phase detection circuit

A method of transmitting information over POTS wiring includes transmitting a first delimiter signal, in the form of a multi-cycle waveform having a frequency of approximately 7.5 MHz, over the POTS wiring. A second delimiter signal, also comprising a multi-cycle waveform, is then later propagated over the POTS wiring. The time duration between the respective propagations of the first and second delimiter signals defines a symbol, which encodes information. The time duration is also such that reflections on the carrier medium resulting from the propagation of the first delimiter signal decay to a predetermined level prior to propagation of the second delimiter signal.

Method and apparatus for transmitting and receiving a symbol over pots wiring using a multi-cycle waveform

A novel magnetic data storage method is disclosed for storing digital data in a magnetic medium. According to the present invention, the digital data is represented by the interval between two consecutive biphasic magnetic pulses recorded in the magnetic medium. In addition, additional data can be encoded in the pulse width of each biphasic magnetic pulse so that higher data encoding ratio can be achieved.

Biphasic multiple level storage method

A capacitor discharging circuit for discharging a potential on a capacitor when the capacitor is decoupled from an AC source. This circuit is particularly useful where the capacitor is unplugged from an ordinary AC power socket.

Capacitor discharging circuit

A method and apparatus for decoding a symbol, having a time duration indicative of a bit sequence and determined by first and second delimiters being with the detection of the first delimiter of the symbol on a carrier medium. A predetermined blanking interval is measured following detection of this first delimiter. Detection of the second delimiter on the carrier medium is prevented prior to expiration of the predetermined blanking interval. This is to prevent the detection of reflections resulting from the propagation of the first delimiter over the carrier medium, and the incorrect identification of such reflections as the second delimiter of the symbol. The valid second delimiter of the symbol is then detected on a carrier medium subsequent to expiration of the predetermined blanking interval. A symbol, indicative of the bit sequence, is identified from a group of symbols based on the time duration between the respective detections of the first and second delimiters.

Method and apparatus for decoding a bit sequence for transmission over pots wiring

A voltage compensation circuit is coupled to a conventional milking system so that when a milk stream flows from a cow to a milk pipeline, a voltage compensation circuit makes contact with the milk stream. As a result, due to the voltage compensation circuit's output voltage, a current that might be generated by the electric potential difference between the cow and the milk pipeline is prevented from flowing within the milk stream. Accordingly, electric shocks to the cow are effectively prevented.

Voltage compensation circuit and method for reducing electric shocks to teats of an animal during its milking

An encoding/decoding method for a signal having at least two different positive and negative levels. Each symbol representing, for instance, two binary bits is encoded in each symbol period. During each symbol period, the encoded signal transitions between a level of one polarity to a level in the opposite polarity. The levels and transitions are selected so that there is no DC component. The frequency spectrum is shifted away from the lower frequencies with this encoding.

Encoding/detection method for digital data transmitter with a signal

A binary data encoding and decoding technique that alternates between starting polarities of a signal for both each occurrence of a binary 1 and each occurrence of two or more consecutive binary 0's. To encode a binary 1, the signal is one polarity for one-half of a bit interval and then the other polarity for the other half of the bit interval. To encode a binary 0, the signal remains at a zero level, unless there are two or more consecutive binary 0's, in which case the signal will be one polarity for the second half of the first binary 0 bit interval, the other polarity for the first half of the second binary 0 bit interval, and repeat this waveform for every for every two adjacent binary 0's. Decoding occurs by examination of either the signal level as compared to predetermined cut-levels, or the time equivalent distance between the peaks. In the first case, if the signal is above the upper cut-level or below the lower cut-level, a binary 1 is decoded; if it is between the upper cut-level and the lower cut-level a binary 0 is decoded. Alternatively, every occurrence of a peak is decoded as a binary 1 and the number of binary 0's between these binary 1's is determined by the time equivalent distance between peaks.

Growing community of inventors

Berkeley, CA, United States of America

Martin H Graham