Abstract: The invention comprises apparatus for forming nelical coils from conductive strip metal, counting the turns and cutting them to separate the turns into coils of desired numbers of turns, annealing the coils, tabbing the ends thereof, coating the coils with insulative coating and curing the coating by baking; compressing the so-insulated coils under extreme pressure to comprise a helical coil product, per se, or to fit conventional cores to comprise an inductor product.

Abstract: The invention comprises a tachometer for aircraft for determining engine operating parameters from magneto signals from right and left magnetos. A signal conditioning circuit receives ignition signals from at least one magneto and modifies the ignition signals to provide a right and left train of input pulses for the microprocessor. The microprocessor follows a stored program to develop filtered quantitites depicting right rpm, and left rpm for respective right and left engines, or right and left magnetos of a single engine. The maximum rpm achieved during operation is also stored, along with the difference between the right and left rpms, the change in rpm over a period of time, and average rpm of two engines. A mode switch selects from right rpm, left rpm, maximum rpm, difference rpm, change in rpm over time, and average rpm for display on the display means. A method for calculating highly accurate engine RPM is disclosed.

Abstract: A silicon-on-sapphire semiconductor structure, and method of fabricating such structure, in which a silicon nitride layer is provided over the oxide layer. The silicon nitride layer is disposed over the upper edge of the silicon island, and acts to prevent gate oxide breakdown.