Abstract: A detector for detecting a characteristic and a speed of a vehicle includes a first magnetic field sensor. The first magnetic field sensor includes a magnetically variable resistor that changes resistance in response to being exposed to a magnetic field. A bias is applied to the magnetically variable resistor and a change in the resistance thereof in response to an applied magnetic field is detected by an amplifier. The amplifier generates a first analog signal indicative of changes in the resistance of the magnetically variable resistor. A differentiating circuit differentiates the first analog signal and produces a first output that changes binary state in response to detecting a predetermined change in the differentiated first analog signal. A counter accumulates values at a predetermined rate and a microprocessor stores values of the counter corresponding to each change in the binary state of the first output of the differentiating circuit.

Abstract: A detector for detecting a characteristic and a speed of a vehicle includes a first magnetic field sensor for generating a first analog signal indicative of changes in magnetic field strength adjacent the first sensor in response to the vehicle passing. A differentiating circuit differentiates the first analog signal and produces a first output that changes binary state in response to detecting a predetermined change in the differentiated first analog signal. A counter accumulates values at a predetermined rate and a microprocessor stores values of the counter corresponding to each change in the binary state of the first output of the differentiating circuit. The microprocessor converts the stored counter values into a first time series profile corresponding to changes in the first output of the differentiating circuit and accumulates and stores a count of a characteristic of the passing vehicle based on the first time series profile.

Abstract: A sensor for detecting a magnetically permeable mass by the disturbance of the earth's magnetic field in the vicinity of the sensor comprises a ferromagnetic strip with a conductive winding wrapped thereabout, a means for magnetically biasing the strip such that regardless of orientation the earth's magnetic field and the strip placing the ferromagnetic strip in a position on its BH curve where the slope is substantially linear, a means for generating an analog signal indicative of the inductance of the winding as the earth's magnetic field is disturbed in the vicinity of the ferromagnetic strip causing a change in the inductance of the winding, a means for digitizing the analog signal at spaced time intervals to produce a series of digitized values, and a digital computer means for processing the digitized signal values to characterize the presence and/or motion of the permeable mass.

Abstract: Method and apparatus are disclosed for storing and recovering a digital signal indicative of digital data wherein an audio cassette tape recorder is used to record, in analog form, digital data. The playback signal is processed through circuitry to produce one signal indicative of positive peaks in the playback signal, and a second signal indicative of negative peaks. The set and reset terminals of a flip-flop are responsive respectively to the latter two signals so as to reconstruct the original data signal at the output of the flip-flop.

Abstract: An electrical bi-directional motion sensing and clocking system is disclosed for identifying the relative sense and magnitude of movement experienced by a moving body. The corresponding relative motion of a target past a pair of sensor units produces a pair of input signal pulses from the sensors for each increment of movement experienced by the moving body. Each occurrence of such a pair of input pulses is recorded and gives rise to a clock output signal upon the recorded occurrence of both input signals. The relative occurrence sequence of the two input signals is also recorded and utilized to provide a respectively corresponding output representing the direction of body movement to be associated with the detected movement increment. The system is arranged so as to suppress spurious output signals which might otherwise be generated when the relative sequence of input signals is reversed at any arbitrary point in the cycle of detecting an increment of motion.