Abstract: A system and method for charging a battery to a threshold voltage. The battery has an output voltage that is lower than the threshold voltage when undercharged. A switch is provided that controls a current flow to the battery. The switch alternates between a closed state and an open state, wherein the current switch only connects the current source to the battery when in the closed state. A sample and hold circuit is provided that samples the output voltage of the battery each time the current switch is in its open state. This produces a saved voltage value. A comparator is used to compare the saved voltage value of the rechargeable battery to the threshold voltage. The charging current is stopped when the comparator determines that the output voltage of the rechargeable battery is at least as great as the threshold voltage.

Abstract: A recharging system for a battery. The internal resistance of the battery and its leads produce an error voltage when a charging current flows through the battery and the leads. The error voltage combines with the inherent battery voltage to produce an inflated voltage. A filtering circuit receives the inflated voltage. The filter circuit quantifies the error voltage. A subtractor circuit receives the inflated voltage and the error voltage. The subtractor circuit subtracts the error voltage from the inflated voltage to quantify the battery voltage. A voltage comparator is utilized to compare the battery voltage to a voltage set point. A switch is provided that is controlled by the voltage comparator. The switch receives the charging current and directs the charging current to the only while the voltage set point is greater than the battery voltage. Thus, the battery is recharged.

Abstract: A system and circuit for recharging a battery using an AC power source. A tuned circuit is created using a capacitor, an inductor, a rectifier and the battery being recharged. The rectifier and battery combine to create circuitry that is equivalent to an AC component. The equivalent circuitry is in series with the inductor. The capacitor is in parallel with the inductor and equivalent circuitry. The resultant circuit is tuned and can be operated at a resonance frequency. In operation, the tuned circuit provides a recharging current to the battery without the need for a transformer or current resistive elements. The result is a recharging system and circuit that is smaller, lighter and far more power efficient than prior art battery chargers.

Abstract: A recharging system for a battery. The internal resistance of the battery and its leads produce an error voltage when a charging current flows through the battery and the leads. The error voltage combines with the inherent battery voltage to produce an inflated voltage. A filtering circuit receives the inflated voltage. The filter circuit quantifies the error voltage. A subtractor circuit receives the inflated voltage and the error voltage. The subtractor circuit subtracts the error voltage from the inflated voltage to quantify the battery voltage. A voltage comparator is utilized to compare the battery voltage to a voltage set point. A switch is provided that is controlled by the voltage comparator. The switch receives the charging current and directs the charging current to the only while the voltage set point is greater than the battery voltage. Thus, the battery is recharged.

Abstract: A solid state circuit breaker for disrupting the flow of direct current. A power transistor is used in series with the direct current. The power transistor disrupts the direct current only when it is in an off state. A first optoisolator and a second optoisolator are provided. The second optoisolator selectively alters the power transistor to its off state. The first optoisolator selectively controls the second optoisolator. A threshold resistor is provided through which the direct current passes. The threshold resistor creates a voltage differential. The voltage differential is supplied to the first optoisolator and activates the first optoisolator if the voltage differential is greater than a selected threshold voltage.

Abstract: A correction circuit and method that is used in a system that produces an initial signal and has downstream components that adds a distortion error to that initial signal. The distortion error is added to the initial signal by the downstream components in the system. This creates a distorted output signal. The distorted output signal is then subtracted from the initial signal to obtain an initial negative distortion error. The initial negative distortion error is subtracted from the initial signal to create an initial conditioned signal. The initial conditioned signal is supplied to the electronic component of the system in place of the initial signal. The result is a reduction in distortion and noise that loops and adapts to changing signal patterns.

Abstract: A circuit for monitoring the functionality of an electrical element. A primary power supply provides direct current to the electrical element at a current sufficient for the electrical element to operate. A Schottky diode is disposed between the primary power supply and the electrical element, wherein the electrical element draws its operational current through the Schottky diode when in operation. A reverse bias power supply is provided. An opto-isolator is disposed between the reverse bias power supply and the electrical element. The electrical element draws a secondary current from the reverse bias power supply through the opto-isolator. The opto-isolator creates an output signal that is indicative of the secondary current. The output signal is used to control a remote failure indicator. When the electrical element fails, the current flowing through the opto-isolator stops. This triggers the failure indicator and informs a user as to the failed status.

Abstract: A tubular test chamber of square cross-section minimizes reflection of stray light from the interior surface of the test chamber onto the detector during measurement by an optical system which is based upon right angle light scattering by the dust particles of a test sample. A rotary solenoid is utilized to open a trap door through which a sample is dropped into the test chamber during energization so that the internal spring of the solenoid can be used to bias the door closed upon deenergization thereof. The electronic circuitry which supports the measurement process provides an output in the form of a single "characteristic number" for each sample measured and has a novel feedback circuit used in auto-zeroing of the device.