Abstract: An improved detector is provided for installation in a roadway surface. The detector finds utility in a highway vehicle detection system for determining vehicle presence, vehicle speed and vehicle length. First and second matched induction coil magnetic sensors are maintained at or near the roadway surface. Each of the sensors has a longitudinal axis aligned normal to the roadway surface. The first and second sensors are separated from one another by a known distance in a direction substantially aligned with a direction of traffic flow. Each of the sensors generate a differential magnetic field signature with respect to time to indicate a passing vehicle's leading and trailing edge magnetic signatures. Vehicle speed is determined by a time-distance relationship using the leading and trailing edge magnetic signatures and the known distance. Vehicle length is determined by a time-speed relationship using the leading and trailing edge magnetic signatures and the determined vehicle speed.

Abstract: The blocking disc serving as an explosive train interrupter of a safety and rming mechanism is angularly displaced from its safe position by a stepping motor through reduction gearing in response to timed energizing pulses applied thereto from a crystal-controlled pulse generator. The blocking disc is releasably latched in its safe position by a locking rod controlling the supply and cut-off of energizing voltage to the pulse generator to accurately time displacement of the disc to an armed position.

Abstract: The blocking disc serving as an explosive train interrupter of a safety and rming mechanism is angularly displaced from its safe position by a stepping motor through reduction gearing in response to timed energizing pulses applied thereto from a crystal-controlled pulse generator. The blocking disc is releasably latched in its safe position by a locking rod controlling the supply and cut-off of energizing voltage to the pulse generator to accurately time displacement of the disc to an armed position.

Abstract: A portable electromagnetic field exposure dosimeter includes a triaxial fite-loaded coil sensor, a group of amplifiers and bandpass filters, a data control board, and a computer. The triaxial sensor receives electromagnetic radiation along three orthogonal axes for measurement which is channelled through a group of amplifiers and then bandpass filtered into three frequency signal ranges. One frequency range corresponds to exposure at 60 Hz and two of its harmonics. The second frequency range corresponds to high frequency pulsed energy. The third frequency range reflects body motion of a tested individual. The data control board converts such filtered signals into digital code and controls the flow of the converted data to random access memory and to the computer. The computer performs a Fast Fourier Transform on the converted data from the 60 Hz frequency range and then stores or displays the analyzed data as a function of frequency and time.

Abstract: A liquid crystal display panel having a backlight for providing high brigess, uniformity of illumination intensity, high efficiency, and long battery life, and which can be manufactured at a low cost. The display device includes a liquid crystal display panel, a light source for illuminating the liquid crystal panel, a light passage member which can be formed of a transparent material disposed between the liquid crystal panel and the light source. The light source inlet side of the light passage member is formed with a recess with the thickness being reduced at the region diametrically opposed to the light source. A light reflecting member reflects light from the light source. Within the photoconductor, two or more of the wedged shaped photo conductor can be used for increased area of coverage.

Abstract: A hand held, shoulder mounted gun with time delay circuitry means to safely ignite a powdered pyrotechnic material.

Abstract: A digital compass including a two-axis earth's magnetic field sensor and a earing processor computes the bearing for local display or transmission from a remote site to a local site for display and/or storage. The bearing processor portion of the digital compass includes an analog-to-digital converter configured for ratiometric measurements to compute the ratio of the x-axis and y-axis signals (smaller divided by the larger) from the aforementioned two-axis earth's magnetic field sensor. A programmable memory unit controlled, inter alia, by the data line outputs of the analog-to-digital converter, contains the arc tangent function for angles from 0.degree. to 90.degree.. The data line outputs from the memory unit defines a quadrant displacement angle in the range of 0.degree. to 90.degree. which is subsequently added to the cardinal point forming the lower boundary in bearing of the host quadrant.

Abstract: An improved self-powered vehicle detector (SPVD) uses a two-axis magnetomr to sense a vehicle's magnetic signature and then telemeter vehicle presence information to a roadside receiver. The SPVD system includes digital nulling loops to cancel D.C. offset changes in the magnetometic output, a multi-tone code transmitter to transmit vehicle presence and SPVD condition signal, and an omnidirectional microstrip antenna to simplify installation and maintenance of the SPVD.