A circuit for detecting and indicating the actual state of charge of a storage battery in response to signals sampled from various points in the circuit powered by the battery. Such circuit is adapted to calculate the open circuit voltage of the battery, it being realized that the open circuit voltage is directly proportional to the battery state of charge. A function generator is constructed to simulate the characteristic curve of the battery relating the internal resistance to the percent char...

A method of manufacturing an electrical solid-state device in which the separation of adjacent areas of film material is controlled at a low value. The method employs established photoengraving techniques, and exploits the undermining of edges of photo-resist when the film material is etched away. The etching action is continued after exposure of the substrate, until the wall of film material recedes sufficiently to give a stable wall profile and a margin of exposed substrate which is overhung b...

Electrolyte from a battery cell is circulated by pump, through a container which contains a hydrometer float, and back to the cell. The float has an opaque neck which interrupts light passing from a light source assembly to a light receiving assembly, and the receiving assembly controls slave means, which can be an illuminated sign, as for example a group of visible light emitting diodes, the number of which illuminated indicating the density of the electrolyte. The slave means can alternatively...

A solid state keyboard comprised of a base module, a plurality of key members each having a plunger member comprised of a uniform mixture of a magnetic material such as barium ferrite and a binder such as nylon, and a respective plurality of improved Hall Effect generators, provides a significant improvement in performance and cost effectiveness. Actuation of a key member moves its plunger member, which has a preselected magnetic field, in rectilinear fashion relative to an improved Hall Effect ...

Photo sensitive elements formed on a surface of a substrate are arranged in rows and columns. Column conductors for selectively collecting the information contained in the photo elements are diffused along the length of each column in the same surface of the substrate as the photo elements. A barrier region is formed between the photo elements of each column and their associated column conductor for, normally, preventing leakage of charge from the diffused column conductors back into the photo e...

A solid state ignition system for generating high frequency and high energy electrical pulses, the system providing improved performance under varying line voltage conditions, improved voltage regulation, and reduced power dissipation, and being effective to produce an improved ionization arc between electrodes effective to initiate fuel oil combustion.

A method of manufacturing a solid state sensor wherein a reactive compound of an alkali metal is tightly packed between a central electrode and a surrounding ion shield. A heating coil is wound about the outside of the shield. The ion shield is formed of a material that is deplete in ions of alkali metal and serves as a ion depletion boundry in the system.

A layer of a solid state compound including at least one compound selected from the group of fluorine and lead which compound prominently changes its light absorption factor when an electric field is applied thereto, thereby becoming black during the application of the electric field. Therefore, the solid state compound layer provided with at least an electrode on one face thereof can be used as a display device or a recorder.

A delta modulation system with an encoder for encoding successive samples of an analog signal during successive sample intervals into a digital status change code signal indicating the difference between a sample and an estimate of the sample as one of three states: increasing, decreasing or unchanged in status. The status change code signal is transmitted to a decoder which reconstructs the analog signal from the digital status change signal. The status change code signal is also used in the en...

The manufacture of solid state cells with smearable cathode materials subject to radial expansion during cell discharge is improved by the consolidation of such materials within a radially rigid non-flexible wall-retaining member which serves as a jig for the cathode during the fabrication of the cell, and which is thereafter retained in the cell structure to control such radial expansion.