Abstract: A system for detecting a target substance within a class of explosives and narcotics containing quadrupolar nuclei through the use of nuclear quadrupole resonance (NQR). The system applies an RF signal to a coil (34) to excite the substance under test. If the target material is present, an NQR signal will be picked up by the same coil, That signal is compared with known NQR signals in frequency and amplitude. A signal is displayed in an appropriate way if a threshold value of the NQR signal is equalled or exceeded. The empty coil is statically tuned by means of adjusting the location or capacitance values, or both, of static tuning capacitors (102) in the coil. The coil is tuned after the specimen is inserted into the coil by means of an auto-tune feature (36). Effective RFI shielding (37) is provided to prevent external contaminating signals from being detected by the coil and to prevent RF signals from escaping from the scanner. The invention also includes the method for performing tests with the system.

Abstract: A system for detecting a target substance within a class of explosives and narcotics containing quadrupolar nuclei through the use of nuclear quadrupole resonance (NQR). The system applies an RF signal to a coil to excite the substance under test. If the target material is present, an NQR signal will be picked up by the same coil. That signal is compared with known NQR signals in frequency and amplitude. A signal is displayed in an appropriate way if a threshold value of the NQR signal is equalled or exceeded. The coil is tuned by means of an auto-tune feature. Effective RFI shielding is provided to prevent external contaminating signals from being detected by the coil and to prevent RF signals from escaping from the scanner. The invention also includes the method for performing tests with the system.

Abstract: A wear-resistant thermal printhead employs a wearplate deposited atop the printhead substrate adjacent the resistive print element as a hard shield to impacting tickets and abrasive material propelled across the printhead. The wearplate comprises a layer of thick film glass doped with a suitably hard material such as zirconia, alumina, or diamonds. Printhead position is adjusted so that the wearplate is impacted instead of the print element and conductive traces carrying current to the print element are routed out of the way along the backside of the substrate opposite the side subject to abrasion.

Abstract: A logic element which provides a unique output for each unique, non-contemporaneous, non-repetitive sequence of input signals; and a method of synthesis of non-contemporaneous, non-repetitive sequences according to the temporal order of the input signals.

Abstract: A flux-sensitive magnetic head employs, at its back part, a structure having a thin single domain magnetic film coated thereon. A coil wraps around the coated structure, and a direct current is passed through the coil, thereby to apply a hard axis magnetic bias to the film. Signal flux appearing at the head front gap asserts a magnetic force along the hard axis of the film. Contrary to what would be expected, the signal flux causes the inductance of the coil to vary. Such inductance variation may be conveniently detected by (1) connecting the variable inductor into a tank circuit, (2) applying a high frequency ac ripple to the "hard axis" dc bias, and (3) measuring the "hard axis" detuning experienced by the tank circuit.

Abstract: In a magnetic head of the type having a thin film magnetically-coated electrically-conductive wire bridging the windowed back section of the head, excitation currents are applied to the wire within the windowed head section.

Abstract: A flux-sensitive magnetic head employs, at its back part, a structure having a thin single domain magnetic film coated thereon. A coil wraps around the coated structure, and a direct current is passed through the coil, thereby to apply a hard axis magnetic bias to the film. Signal flux appearing at the head front gap asserts a magnetic force along the hard axis of the film. Contrary to what would be expected, the signal flux causes the inductance of the coil to vary. Such inductance variation may be conveniently detected by (1) connecting the variable inductor into a tank circuit, (2) applying a high frequency ac ripple to the "hard axis" dc bias, and (3) measuring the "hard axis" detuning experienced by the tank circuit.

Abstract: The source of anomalies in the performance characteristics of a magnetic head employing a sense wire having a thin film coated thereon and a coil coupled therewith is explained. Solution to the problem anomalies centers around use of a mandril for the coil.

Abstract: A digital type controller for a punch press or the like which includes a shaft angle encoder for generating control pulses corresponding to specific main shaft angles of the machine, a plurality of sensors for generating signals in response to the operating condition of the machine and process, a plurality of circuits for enabling the reception of said signals at selectable shaft angles of the machine, a plurality of circuits for enabling the reception of said signals in a selectable prescribed order, a plurality of circuits for storing said signals, a plurality of circuits for sampling the stored signals at selectable shaft angles of the machine, a plurality of circuits which detect the presence or absence of the sampled signals, an output circuit for deenergizing the machine Run control circuit when an absence of a sampled signal occurs, a plurality of circuits for energizing and deenergizing external electrical loads at selectable shaft angles of the machine, and a shaft encoder/decoder which provides cont