Abstract: An anti-fuse having two electrical connections is constructed by adding at least one zener diode and resistor to a power MOSFET. When the voltage across the two electrical connections exceeds the zener diode voltage and the maximum gate voltage of the MOSFET, the MOSFET burns out. This shorts out the device which can be used to bypass an LED or other load when that load burns out and forms an open circuit.

Abstract: Reliability of devices such as lighting fixtures, is improved by replacing an inductor based voltage inverter to power the device with a switching constant current PWM controller. Avoiding use of an inductor and matching capacitor is made possible by a high voltage power input that exceeds the voltage requirements of the device. The power is pulse width modulated with a current feedback to control duty cycle, and thus average device current.

Abstract: Solar electricity is used more efficiently and at lower cost via the technique of interrupted DC power. Interrupted DC removed the spark problem from high voltage DC circuits, allowing their use with normal appliances. Wasteful and expensive inductor based voltage changes were avoided by adjusting solar panel output voltage via loading. This provided prioritization of use among appliances. Furthermore, the extreme decrease in sparking obtained by interrupted DC allows for the manufacture and use of lower cost direct current circuit breakers that are self powered and provide protected circuits of greater than 99% direct current purity.

Abstract: Reliability of devices such as lighting fixtures, is improved by replacing an inductor based voltage inverter to power the device with a switching constant current PWM controller. Avoiding use of an inductor and matching capacitor is made possible by a high voltage power input that exceeds the voltage requirements of the device. The power is pulse width modulated with a current feedback to control duty cycle, and thus average device current.

Abstract: Direct current (“DC”) power such as from solar panels is used by home appliances directly without conversion to AC. The large direct current spark problem is alleviated by interrupting the DC current at periodicities of at least 120 hertz and typically 99 percent duty cycle. This interrupted DC power is less harmful to switches and circuit breakers than equivalent AC power. Furthermore, the interrupted DC power is used with greater efficiency by computers, and can be used to power a wide range of appliances. Exceptions are inductive appliances, which are detected and treated differently, by a smart power receptacle embodiment. These embodiments provide a very low cost and efficient path to an all DC electric power future.

Abstract: Solar electricity is used more efficiently and at lower cost via the technique of interrupted DC power. Interrupted DC removed the spark problem from high voltage DC circuits, allowing their use with normal appliances. Wasteful and expensive inductor based voltage changes were avoided by adjusting solar panel output voltage via loading. This provided prioritization of use among appliances. Furthermore, the extreme decrease in sparking obtained by interrupted DC allows for the manufacture and use of lower cost direct current circuit breakers that are self powered and provide protected circuits of greater than 99% direct current purity.

Abstract: Direct current electric grids are provided that allow independent power generation and consumption at the neighborhood level. In an embodiment power is uploaded and downloaded to each node via monitoring of node voltage and setting high vs low priority loads to optimize for maximum power usage. Embodiments allow a new paradigm wherein electrical supply is set by total available installed power generation and wherein all available power is used, via prioritization. New apparatuses and circuits are provided that provide higher efficiency by utilizing solar power generated at low light conditions and by minimizing the number of power alteration steps between power generator and power consuming device.

Abstract: The disclosed smart receptacle allows use of high voltage DC power, typically between 100 and 120 volts, for regular appliances such as computers and cell phone power adapters, coffee pots, heaters and some motorized devices. The receptacle prevents use of the DC power by AC appliances by monitoring for amount and or quality of inductance of a plugged in appliance. Other embodiments include local grid structures that provide locally resilient sources of energy, particularly solar electric energy, and methods for sharing power. One such embodiment provides a comprehensive apparatus that provides energy cost lowering and backup power by connection to utility power and to DC power such as from a DC grid or solar panels, while providing power to DC appliances.

Abstract: Direct current (“DC”) power such as from solar panels is used by home appliances directly without conversion to AC. The large direct current spark problem is alleviated by interrupting the DC current at periodicities of at least 120 hertz and typically 99 percent duty cycle. This interrupted DC power is less harmful to switches and circuit breakers than equivalent AC power. Furthermore, the interrupted DC power is used with greater efficiency by computers, and can be used to power a wide range of appliances. Exceptions are inductive appliances, which are detected and treated differently, by a smart power receptacle embodiment. These embodiments provide a very low cost and efficient path to an all DC electric power future.

Abstract: The disclosed smart receptacle allows use of high voltage DC power, typically between 100 and 120 volts, for regular appliances such as computers and cell phone power adapters, coffee pots, heaters and some motorized devices. The receptacle prevents use of the DC power by AC appliances by monitoring for amount and or quality of inductance of a plugged in appliance. Other embodiments include local grid structures that provide locally resilient sources of energy, particularly solar electric energy, and methods for sharing power. One such embodiment provides a comprehensive apparatus that provides energy cost lowering and backup power by connection to utility power and to DC power such as from a DC grid or solar panels, while providing power to DC appliances.

Abstract: Solar electric energy is optimally used by varying one or more connected loads to achieve a maximum output power voltage. Entire appliances may be switched on or off, or modulated, as in the case for example of a heat pump compressor circuit or electric water heater. Variations of this theme are used to prioritize appliance usage for overall improved convenience and efficiency. Solar electric appliances such as refrigerators, freezers, air dryers and water pumps are described. This and other electric sources may be used to power electric garden tools. Electric distribution tools and methods are described as well as electric garden tillers with features such as semi-control and smooth operation.

Abstract: Direct current electric grids are provided that allow independent power generation and consumption at the neighborhood level. In an embodiment power is uploaded and downloaded to each node via monitoring of node voltage and setting high vs low priority loads to optimize for maximum power usage. Embodiments allow a new paradigm wherein electrical supply is set by total available installed power generation and wherein all available power is used, via prioritization. New apparatuses and circuits are provided that provide higher efficiency by utilizing solar power generated at low light conditions and by minimizing the number of power alteration steps between power generator and power consuming device.

Abstract: Solar electric energy is optimally used by varying one or more connected loads to achieve a maximum output power voltage. Entire appliances may be switched on or off, or modulated, as in the case for example of a heat pump compressor circuit or electric water heater. Variations of this theme are used to prioritize appliance usage for overall improved convenience and efficiency. Solar electric appliances such as refrigerators, freezers, air dryers and water pumps are described. This and other electric sources may be used to power electric garden tools. Electric distribution tools and methods are described as well as electric garden tillers with features such as semi-control and smooth operation.

Abstract: Marching band string instruments and wearable string instruments are described that include a stiff waist band to prevent excessive side to side movement during use, while providing easy doff and don of the string instrument. String instruments also are provided with adjustable chest braces to allow accommodation for different player sizes and for minimization of back strain when playing the electric string instrument for extended time periods. Electric string instruments optionally have soft material interposed between bridge feet and a string instrument body, to allow a more resonant sound detection from a pickup located between the bridge feet and the body. Other advances include generation of a stereo signal from bridge vibrations, and electronic processing of sound that enhances the electric string instrument playing and learning experience.

Abstract: Marching band string instruments and wearable string instruments are described that include a stiff waist band to prevent excessive side to side movement during use, while providing easy doff and don of the string instrument. String instruments also are provided with adjustable chest braces to allow accommodation for different player sizes and for minimization of back strain when playing the electric string instrument for extended time periods. Electric string instruments optionally have soft material interposed between bridge feet and a string instrument body, to allow a more resonant sound detection from a pickup located between the bridge feet and the body. Other advances include generation of a stereo signal from bridge vibrations, and electronic processing of sound that enhances the electric string instrument playing and learning experience.

Abstract: Rapid shaft stop devices and transmissions are described that utilize permanent magnets for coupling and/or braking and are useful for electronic propeller guards and other equipment. In an embodiment, one or more capacitive discharge pulses are used to rapidly stop a shaft. A magnetic transmission is provided having axially oriented magnets on each side of an air space junction that transmit torque across the junction with a torque/speed profile that particularly suits boat propellers. The junction may include a bearing and allows slippage when the propeller resistance exceeds a given value. This slippage acts as a variable gear reduction. One or more electromagnets may be energized and thereby add to or subtract from one or more magnetic fields and provide electronic control of torque and of gear reduction ratio for devices such as watercraft drive systems.

Abstract: Readout devices and controls are provided that alert the user to unusual propeller slip conditions. Embodiments of the invention incorporate some signal processing to account for a progressively greater slip at lower watercraft speeds. Thus, the invention provides simple information that tells the user if a boat propeller combination is being operated suboptimally, without requiring the knowledge and use of multiple slip figures for differing boat speeds. The invention allows greater economy of operation, automatic anticavitation control and can alert the watercraft operator to unusual conditions such as anchor down, propeller up other situations that affect propeller loading.

Abstract: Advances in electric power storage, monitoring, control and use in electric motors are described from the viewpoint of their optimal use in electric watercraft. Electric motor overspeed capability is provided to allow a wider range of performance from electric motors. Monitors and useful ways of constructing electric power supplies such as cost performance monitored batteries for electric motors and hydrogen absorbent chambers for fuel cells are further described. Such devices and methods provide greater efficiencies, greater convenience and improved flexibility for operators and riders of watercraft, land vehicles, airplanes and other devices.

Abstract: Electronic methods, devices and kits electronically protect swimmers, animals and other objects in water from propeller strikes, and alleviate propeller damage. Desirable embodiments include continuous ultrasonic sensing and detection by separate sensors to minimize reaction time for stopping internal combustion engine and electric motor driven propellers. Electric boats having direct drive to propellers are particularly amenable for electronic propeller protection. A variety of sensors may be used, including tactile, ultrasonic, galvanometric and infrared sensors. Optionally, the devices and systems can improve performance, safety and economy of boat rental operations by discouraging, limiting and even reporting propeller strikes to a boat custodian, who may be at a different location when the boat is used.

Abstract: Electronic control systems, devices and algorithms are described for improving boat efficiency, safety and convenience, particularly for electric motor powered boats. The overall efficiency of electric boat propulsion is improved by matching the needs of the propeller with the magnetic field requirements of the motor. Efficiency also is improved by limiting slip at different boat speeds. Rapid and fully electronic propeller shut off systems also are described for enhancing public acceptance of electric boats and more convenient cruise control systems are described for improving public acceptance of the boating experience.