Abstract: A masked compare circuit for comparing a first N-bit dataword to a second N-bit dataword, the circuit including a decoder for receiving an M-bit mask code and generating an output signal identifying a bit position, K, derived from the M-bit mask code, M and K being positive integers; and a comparator module responsive to the decoder output signal for comparing the N-K+1 most significant bits of the first dataword to corresponding bits of the second dataword, the comparator module generating an output signal having a first value when all of the compared bits are the same and having a second value when any of the compared bits are different.

Abstract: A data processing system, for processing programs in the form of networks of connected processing elements each relating to an arithmetic or logical operation, includes a memory for storing code representations of the processing elements and process data, processing apparatus including address computation circuitry for generating addresses for the memory and arithmetic and logic circuitry for processing the process data. A finite state machine receives the code representations of the processing elements and generates control signals for controlling the address computation circuitry, arithmetic and logic circuitry and memory in response to the nature of the processing element.

Abstract: An electromagnetic dispersive delay line (10) includes a dielectric strip (28) as well as a coupler (24, 34, 36, and 38) for launching surface electromagnetic waves into the dielectric strip. The upper surface of the dielectric strip (28) is left exposed to the air in order to provide an interface with a lower-permittivity medium of propagation. This permits a surface-electromagnetic-wave propagation mode. The thickness of the dielectric strip (28) is varied along its length so as to result in a linear relationship of delay to frequency throughout a predetermined frequency range. Preferably, a conductive strip (26) spaced from the dielectric strip extends along the surface-wave propagation path in the region occupied by the evanescent field external to the dielectric strip (28). This conductive strip (26) modifies the phase relationships between the electric and magnetic fields in the evanescent-field region so as to cause some of the power transmission to occur outside of the dielectric strip.

Abstract: A comparison circuit which is both window addressable and content addressable, the circuit including comparison elements which include a pair of match transistors which isolate outputs indicating whether an input is not greater than stored data and whether an input is not less than stored data from an output indicating whether an input is equal to stored data.

Abstract: An ultrasonic medical imaging apparatus provides an ultransonic transducer constructed with polyvinylidene fluoride. Circuitry is included for generating an energizing pulse for the transducer, the pulse having a predetermined period and an instantaneous frequency which is varied from a first frequency to a second frequency during the period. Circuitry is provided for digitizing electrical signals from the transducer which electrical signals represent ultrasonic reflections received by the transducer in response to the energizing pulse, and a signal processor cross-correlates the digitized electrical signals with the energizing pulse.

Abstract: A memory control for use with a digital oscilloscope having a display and a digital memory storing a sequence of signal samples. The sequence of signal samples is cyclically read from memory and displayed. The memory control adjusts the memory access operation to provide a controlled signal flow to the display at a rate within the slew-rate limits of the graphic display. In the memory control, the point slew, or distance over which the display beam moves from the present data point to the next point, is measured. If the point slew relative to the time interval between displayed signal samples exceeds the slew-rate capability of the display, the signal flow from the memory for subsequent data points is reduced or inhibited for a time sufficient to allow the display to reach a coordinate position corresponding to the desired data point.

Abstract: An electrical waveform generator provides a memory for storing a plurality of data points representing sequential amplitude values of a desired waveform, a digital-to-analog converter for converting the data points to analog voltages for generating the desired waveform and apparatus for selectively coupling the data points to the converter, including apparatus for selecting groups of data points and for selectively looping through the groups.

Abstract: An oscilloscope to sequentially store, process and display an electrical input signal according to various signal events and characteristics. The oscilloscope is physically and functionally modular having both selectable hardware configurations from among various "plug-in" modules and selectable processing and display features chosen from among a predetermined selection by software control contained, in part, within the plug-in modules. The particular control settings, as well as a representation of the signal itself, is recorded on a removable storage device, such as a magnetic disc. High frequency signals are sampled, digitized and stored in a high speed intercascaded signal memory, independent from the program and data memory associated with the oscilloscope signal processing.

Abstract: The present invention generally provides an image display system having display means, image memory means for storing image data in the form of rows and columns of pixels with each pixel having a value representing the intensity level thereof, processor means for processing the image data on a selectable basis and in a selectable manner, and display memory means for receiving and storing image data from the processor means for use by the display means. The method of the present invention provides for displaying images from image data in the form of rows and columns of pixels with each pixel having a value representing the intensity level thereof, comprising the steps of: storing the image data in a random access memory means; selectively reading the image data from the random access memory means; selectively processing the image data read form the random access memory means; storing the processed image data in a display memory means for display purposes; and displaying the stored processed image data.

Abstract: A magnetic tape drive emulator provides interface compatibility between a computer system having an industry standard tape drive interface and a peripheral image acquisition processing system. The emulator receives signals that are normally applied to a magnetic tape drive system and converts them into data signals which are formatted for general access by the image acquisition processing system. In addition, the magnetic tape drive emulator converts signals generated by the peripheral processing system into data signals which are formatted for access by the computer system through the standard tape drive interface.

Abstract: A bank of differential amplifier circuits includes specialized circuits to provide multi-channel differencing with a minimum number of active devices such that the differences between pairs of analog input signals, such as available from patient monitoring electrodes, are derived with half the number of active devices normally utilized. In one embodiment, two operational amplifier circuits are used in a differencing channel which functions together to provide differencing, a properly delayed input signal for use in another differencing channel, high input impedance buffering, a low impedance output for each differential amplifier channel, time-coincident, matched outputs for each differential amplifier channel, and with an additional operational amplifier, a DC rejection circuit which does not affect the low output impedance or the differencing function, thereby to eliminate the necessity of providing separate buffers and active delay circuits which can result in the use of twice the number of active devices.

Abstract: In a hearing aid of the type having an electrical amplifier, wherein the improvement provides an audio signal processing circuit incorporated into the amplifier and including integral computing circuitry for controlling the operation thereof; the processing circuit providing circuitry for receiving an audio frequency electrical signal, circuitry for separating the audio frequency signal into a plurality of frequency bandwidths, circuitry for separately amplifying any audio frequency signal present in each of the bandwidths, circuitry for summing the amplified audio frequency signals from each of the bandwidths to produce a reconstituted signal, and circuitry for controlling amplification including circuitry for sampling any audio frequency signal present in each of the bandwidths and circuitry for determining, in response to the audio frequency signals sampled from all of the bandwidths the amplification level for each bandwidth for the separate amplification.

Abstract: A full floating point vector processor includes a master processing unit having DMA I/O means, a wide bandwidth data memory having static RAM and/or interleaved dynamic RAM, an address generator operative to provide address generation for data loaded in the data memory, a concurrently operating pipeline control sequencer operative to provide fully programmable horizontal format microinstructions synchronously with the addresses generated by the address generator, and a pipelined arithmetic and logical unit responsive to the addressed data and to the synchronously provided microinstructions and operative to evaluate one of a user selectable plurality of computationally intensive functions. The address generator, the pipeline controlsequencer, and the master processing unit are configured in parallel. The address generator includes means operative to provide pipeline input and output data dependent address generation.

Abstract: A continuous wave fan beam tomographic system having continuous x-ray absorption values sampled at a sampling rate and means to provide a best-estimate of the x-ray absorption values at discrete points in time. The means to provide a best-estimate includes a continuous filter having a frequency range defined by the geometry of the mechanical system. Errors due to the statistical variation in photon emissions of the x-ray source are thereby minimized and the effective signal-to-noise ratio of signals is enhanced, which in turn allows a significant reduction in radiation dosage.

Abstract: An isolation circuit provides an isolation amplifier which receives an input signal and feeds a multiplexer switching circuit which is coupled to the primary winding of an isolation transformer. A pair of secondary windings are coupled to demultiplexer switching circuits for reconstructing the original input signal. One secondary winding is thereby used to produce an isolated output signal and the other is used to provide a feedback signal to the operational amplifier. The amplifier and switches are powered by isolated power supplies.

Abstract: A hydrocarbon responsive switch provides an elongated flexible member which is impervious to hydrocarbon substances, a hydrocarbon absorber bonded to the elongated flexible member for absorbing hydrocarbon substances in contact therewith and for swelling from the absorbing for causing the flexible member to bend, a mounting for one end of the elongated member, a first electrical contact located at the other end of the elongated member, and a second electrical contact for contacting the first contact upon bending of the elongated flexible member and thereby making electrical connection in response to the absorption of hydrocarbon substances by the absorber.

Abstract: One of two actuator arms is responsive to a sharp drop in a step of a cam means, the arm engaging the bottom of the step to limit its travel. A striker carried by the arm continues in the direction of the drop to engage an alarm means.

Abstract: A cathode electrode of copper-based material adapted for use in an electrical device is provided with a deposit of silver coated with a finely divided electrically conductive material such as graphite palladium or platinum. The silver deposit is formed by reacting a dilute solution of sodium-silver cyanide with the copper-based cathode electrode. When utilized in an electrolytic capacitor, the cathode electrode helps to increase the capacitance of the cathode electrode and the contact of the copper-based material to an acid electrolyte is uniformly distributed over a large area to provide extended operation with high ripple current with deep cycles of charge and discharge.

Abstract: The electrical connections illustrated in U.S. Pat. No. 3,727,015 have been improved by providing a means of holding the combination electrical terminals and electrical blades in a housing wall to provide more positive electrical connections and by providing a means to connect electrical leads to the combination within the wall.

Abstract: An electrical contact arm is spring biased against electrical paths by a coil spring which is carried on a hub of a rotating member which also carries the electrical arm. An electrically conductive path is also carried by the rotating member to provide switching functions.