Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: A method for measuring the current flowing through a cow is disclosed. The method uses a four-terminal resistor precision measurement technique to accurately measure the electric current flowing through a cow as a result of voltages found on dairy farms. The four-terminal resistor technique allows the present invention to measure the current without the need to account for unpredictable environmental conditions on the dairy farm that may effect electrical contact resistances. The present invention uses Ohm's Law to determine current by dividing the voltage drop across a conductive path in the cow by the resistance of the conductive path. The elements utilized do not restrict cow movements and allow the cow to move about freely so as to enable dairy farmers to monitor conveniently and continuously for electric currents resulting from stray voltages on the dairy farm without interfering with daily farm activity.

Abstract: A child size replica of a western saddle is mounted upon a stand to form a seat. Rollers on the rear of the stand permit the seat to be rolled when the front is lifted. Rubber crutch tips on the front of the stand anchor the seat when it is placed at a dining table with the horn of the saddle under the edge of the table. Experience shows that children sit quietly and peacefully in the saddle at the dining table.

Abstract: The present invention comprises a balun for intercoupling an at least partially unbalanced line and a substantially balanced line having similar line impedances which is capable of passing differential signals over a wide bandwidth while substantially attenuating any common mode signals. The balun comprises a pair of transformers with bifilar windings, each connected as a choke. Each conductor of the unbalanced line is coupled to a different one of two substantially identical inductances of the first transformer and the other side of each inductance is coupled through the second transformer to a different one of the two conductors of the balanced line. Each of the connections between the two transformers is coupled to ground with a substantially identical capacitance. The capacitance in conjunction with the inductance acts to filter out the common mode signals while allowing the differential mode signals to pass through the balun.

Abstract: A method and apparatus for transmitting data over a line where the data is received for transmission at a fixed rate. The data is buffered and transmitted over the line at a rate faster than the fixed rate to create "dead" times used for calibration. Calibration signals are transmitted over the line during the dead time to determine the characteristics of the line.

Abstract: The present invention comprises a balun for intercoupling an at least partially unbalanced line and a substantially balanced line having similar line impedances which is capable of passing differential signals over a wide bandwidth while substantially attenuating any common mode signals. The balun comprises a pair of transformers with bifilar windings, each connected as a choke. Each conductor of the unbalanced line is coupled to a different one of two substantially identical inductances of the first transformer and the other side of each inductance is coupled through the second transformer to a different one of the two conductors of the balanced line. Each of the connections between the two transformers is coupled to ground with a substantially identical capacitance. The capacitance in conjunction with the inductance acts to filter out the common mode signals while allowing the differential mode signals to pass through the balun.