Abstract: A method is provided to connect individual conductive traces to an array of individual piezoelectric elements by bonding a flexible circuit board containing conductive traces to the piezoelectric elements. The resultant bonded elements provide an array for an acoustic transducer.

Abstract: A novel circuit employing a differential integrator having differential inputs V.sub.1 and V.sub.2 provides a substantially uniformly varying output voltage representative of a straight line for connecting two display points having voltage levels V.sub.1 and V.sub.2. This circuit is ideally used in the reconstruction of analog waveforms from digitally stored data for display on an oscilloscope.

Abstract: By coincidentally injecting a predetermined level of direct current with the transmission of data on a transmission line, multiple signal transmissions on the line can be detected by the presence of a DC level greater than a predetermined level on the line. Once detected, tactics for avoiding multiple signal collision problems can be implemented.

Abstract: An adhesive for bonding polyethylene terephthalate, polycarbonate and other transparent thermoplastic sheets to form optically clear laminants with improved bond strengths which remain intact over temperature exposures ranging from -40.degree. C. to 70.degree. C. and humidities ranging up to 90% at 40.degree. C. is provided. The adhesive is a combination of approximately 20% molecular weight phenoxy resin and approximately 80% molecular weight polyurethane resin.

Abstract: A direct flash converter has independent parallel analog-to-digital encoders for each bit. Cross-coupled level sensors are coupled to a single comparator within each bit encoder to provide a directly encoded Gray code binary output.

Abstract: A method is provided for measuring a single-shot time interval using startable oscillators to replicate indefinitely the time interval for averaging. Also provided is a circuit for automatically selecting a proper ratio of division to ensure that the interval being measured is less than the period of replication.

Abstract: An integratable circuit provides a single short pulse in response to a trigger input to the circuit. The circuit relies entirely on internal elements without the use of regeneration for determining the pulse width. Specifically, two signal paths from the input meet at the output to generate the short pulse.

Abstract: A peak detector is comprised of two related circuits having similar circuit parameters, each providing an output in response to a repetitive waveform applied to the detector. The two outputs are combined to eliminate the dependence on the circuit parameters to provide as an output of the detector an accurate, wideband peak voltage of the applied waveform.

Abstract: A velocity decoder system capable of providing information on a wide range of velocities is disclosed. Initially, an estimated velocity of the actual velocity is entered in the system. Then by constantly updating and correcting the estimated velocity in view of the actual velocity, accurate velocity information on a system is obtained almost instantaneously. To broaden the range of velocities decoded without unduly complicating the decoder system or greatly decreasing the sampling rate, circuitry for autoranging that enable utilization of common circuits for different ranges is implemented.

Abstract: A compact resonant cavity with a substantially uniform magnetic field in the cavity is formed by lumped resonantly loading a rectangular primary cavity. The lumped capacitive load is produced by forming secondary cavities on opposite sides of the rectangular primary cavity. The component resonant cavity is designed for applications in atomic frequency standards.

Abstract: A modulating signal is applied to an analog-to-digital converter which addresses a read-only memory phase look-up table. The read-only memory phase look-up table output is applied to a polarity generator. The polarity generator output and output from a phase accumulator are input to a phase adder. The phase adder output is applied to the input of a sine look-up read-only memory whose output is applied to a digital-to-analog converter and low-pass filtered to produce an amplitude-modulated carrier signal. The invention thereby digitally amplitude modulates a carrier signal in the phase domain without any multiplication being required.

Abstract: The interfering resonances of transverse modes are moade to occur far from the fundamental resonant frequency in a surface acoustic wave (SAW) resonator by connecting a plurality of SAW sub-devices in parallel. The frequency response of this parallel combination is essentially undistorted. Interfering spurious resonances caused by the transverse modes become inconsequential. These devices have a substantially higher power handling capability as compared to conventional resonators with comparable Q. This capability reduces the phase noise of oscillators stabilized by these resonators.

Abstract: A magnetic shielding enclosure is fabricated by a simple method of folding magnetically permeable material to provide essentially a gapless two-layered shield with small corner and edge radii.

Abstract: A power supply includes an inverter circuit comprising silicon controlled rectifiers which are driven by a variable frequency control signal. The frequency of the control signal is determined by monitoring the power output requirements of the power supply. Because of the continuous sinusoidal operation of the inverter, the supply generates a very low level of radio frequency interference (rfi).

Abstract: A proportional oven having two heaters mounted to a thermally conductive base stabilizes the temperature of a temperature sensitive crystal mounted on the thermally conductive base by adjusting the ratio of powers applied to the two heaters.

Abstract: A recursive digital low-pass filter processes an input signal with essentially unity gain and sharp frequency cutoff without using multipliers to provide an output signal with an information bandwidth substantially one-half that of the input signal.

Abstract: The present invention provides a silicon gate FET and associated integrated circuit structure in which a second level of polysilicon is selectively oxidized to provide insulating regions where desired. Regions of the polysilicon which were not oxidized are suitably doped to function as electrical interconnects to the source and drain regions in the substrate and to the gate. In the preferred embodiment, a metallic interconnection is made between the gate and drain or source region with the second level of polysilicon.

Abstract: By sealing the periphery of a printed circuit board, the previously exposed edges of the board are substantially prevented from moisture wicking. This sealing of the periphery can be made concurrently with the plating of through-holes on the board. With this process, current leakage paths due to board moisture wicking within the board is significantly reduced.

Abstract: A process is provided for trimming a SAW device while the device is energized and operating at its center frequency. By essentially selectively sputter-etching the substrate or the transducer material only, without requiring a masking operation, the center frequency and other electrical characteristics of the SAW device are trimmed in a precise and controlled manner.