Abstract: A resistor formed by a film of resistive material deposited on a dielectric substrate is trimmed by removing resistive material along a line such that the film is divided into at least two discrete areas, one, and only one, of which areas includes two terminal portions of the film.

Abstract: A high speed four quadrant multiplier is current controlled and uses a high speed differential output current digital to analog converter. Independent adjustment of the multiplying factor without changing the DC offset is accomplished. Also a true zero input signal will cause a true zero output signal and the operation of the multiplier is extremely fast. The analog throughput of the multiplier is independent of the speed of the digital to analog converter.

Abstract: A method and apparatus for generating two phase locked digital clocks of different word rates particularly suited for a graphic and alphanumeric computer display terminal. Master and slave clock generators are used to generate output pulses at every N-th and M-th clocks of a common clock. A phase lock loop including the master clock generator and a phase lock counter dividing the common clock by the factor of the least common multiple of N and M is used to synchronize the slave clock generator.

Abstract: A charge coupled device (CCD) with separately addressable input signal gates is operated in the potential equilibrium mode. With properly selected voltage potentials the CCD can be used as a high speed linear detector of a variable analog signal without the need of preceeding independent sample and hold or peak detector circuits. The result is the efficient minimum/maximum detection of an analog signal in a fast-in/slow-out digitizer.

Abstract: A novel Schmitt trigger circuit is disclosed in which the hysteresis is increased in response to low amplitude input signals and decreased for high amplitude input signals. The result is a trigger circuit which can automatically optimize trigger detection for an oscilloscope or counter in the presence of noise on the input signal.

Abstract: An apparatus for mounting dynamic convergence coils on the neck of a cathode ray tube monitor. Two mounting boards are provided as a mounting platform for the dynamic convergence coils. The mounting boards are pivotably joined so that they may be opened to provide clearance for installation and then closed to clamp onto the neck of the cathode ray tube. Two elastomeric grommets are positioned between the mounting boards and the neck of the cathode ray tube. When fastened together, the mounting boards compress the grommets against the neck. Suction cups on the grommets grip the neck to prevent movement of the mounting boards, and also deform to allow for dimensional variations of the neck.

Abstract: An auxiliary gauging device for a press brake. One end of a locater bar is clamped to the back stop of the press brake. A locating pin is provided on the other end and is adapted to nest in a preformed hole of the work piece. The back stop is positioned relative to the forming tool of the press brake by calculating the distance between the locating pin and back stop, and subtracting the distance between the preformed hole and desired bend line.

Abstract: An oscillator having a circuit for fine tuning the frequency thereof while minimizing any effect on the output amplitude thereof. A state variable oscillator employs an inverter amplifier having a negative feedback resistor R.sub.f, a first integrator, and a second integrator. 180.degree. feedback from the second integrator is fed back through resistors R.sub.i and R.sub.v to an inverting input of the inverter amplifier. 90.degree. feedback from the first integrator is fed back partially through resistors R.sub.n and R.sub.v and partially through resistor R.sub.m to the inverting input, and also through resistor R.sub.c to the non-inverting input. A field effect transistor provides a common return to the non-inverting input to control oscillator amplitude. If R.sub.i R.sub.m =R.sub.n R.sub.f then R.sub.v may be adjusted to vary the frequency of the oscillator output signal without affecting its amplitude.

Abstract: Provided are an apparatus and a method for recording on a recording medium images from a fiber-optic CRT. The apparatus includes a recording medium transport system, control electronics and a first-in, first-out memory. The use of the first-in, first-out memory permits incremental recording which is not limited by relatively long mechanical transport settling times. In operation, N lines of data are input to the memory, line-by-line, as the transport system increments the position of the recording medium and during settling time. When the recording medium has come to rest, these N lines of data are output sequentially from the memory in a first-in, first-out basis, with the CRT incrementing each line vertically on the recording medium for the total of N lines for each increment of the recording medium by the transport system.

Abstract: A microprocessor controlled system is provided which is responsive to displacement information such as rotation rate and position of a rotary knob for controlling instrument functions such as display scrolling, the setting and display of measurement conditions (operating parameters), and the entering and display of alphanumeric data.

Abstract: A state variable oscillator with leveler circuit and with a feedforward circuit for improving the oscillator's rejection of leveler-induced distortion. The feedforward circuit combines a signal representative of a leveler-distorted feedback signal with the main oscillator output to reduce the amount of harmonic distortion, below a certain order, appearing in the output.

Abstract: The invention consists of a transformer coupled low voltage power amplifiers which provides the moderate voltage (200-500 V.sub.p-p) excitation potentials required by PZT ink jet or similar device elements. Transformer coupling is viable in that ink jet drive requirements are "return to zero" (no net DC component). Product safety aspects are enhanced since high voltage power supplies are not required, furthermore significant reductions in cost of implementation are realized due to the absence of high voltage power supplies and by allowing the use of monolithic power amplifiers. Savings in power may also be realized by matching the transformer to the ink jet PZT element as components of a resonant network.

Abstract: A method and circuit for quickly adjusting the frequency of a phase lock loop controlled oscillator to match a reference frequency signal by starting the reference frequency signal at essentially zero initial phase coincident with a zero crossing of the oscillator output. The reference frequency signal is provided by dividing a higher source frequency signal a predetermined amount. Upon receipt of an initialization signal the divider and the phase lock loop are inhibited. Upon the occurrance of a zero crossing the divider and loop are enabled so that the reference signal starts at zero phase within a predetermined period following the zero crossing, and the loop thereafter adjusts the oscillator frequency.

Abstract: Disclosed herein is an apparatus for displaying a logic waveform on a raster scan display device such as a CRT. A part of an input logic signal is delayed for forming a former bit, and the input logic signal acts as a present bit. A memory device stores a special pattern determined in accordance with results of logic operation of the present and former bits. An image dot of the pattern is addressed by the present and former bits and raster line position (number) information, and the output therefrom is applied as an intensity control signal to the display device. Since the memory device does not need FONT information, this invention needs very little software manipulation of data, and the capacity of the memory device is small. In addition, this invention can display glitches and graticule tick marks.

Abstract: An air assisted hand welding tool for clamping and welding conductors together. The tool includes a handle formed of pivotally connected lever-like members. An air passage is connected to an air pressure source provided in the handle of the hand tool. A valve is manually engaged by the operator (following tactile closing of the electrodes on the conductors) to open the air pressure to an expansion chamber formed between the members. As the chamber pressure is increased, the members are urged to a consistent clamping force thereby to assist the operators normal hand clamping function. A switch in the expansion chamber is connected to the welding circuit and is activated following chamber expansion to initiate welding. The entire welding operation including air assist and welding current initiation are all accomplished by a simple closing motion of the operators hand.

Abstract: A document scanner compensates for mechanical misalignment between a document and a photosensitive array by storing pixel information from the array and timing the output of such information in accordance with stored offset values which represent the mechanical misalignment for successive relative positions of the document and of the array.

Abstract: A digital signal sampling system is disclosed for reconstructing the time relationship of digital data signals sampled by two sampling clock signals with different unrelated timebases. The digital data signals sampled may be the same data signal or two different data signals sampled simultaneously in two separate sampler circuits at two different unrelated sampling clock frequencies or timebases to produce first and second sampled data signals. A timebase correlation circuit produces first and second time correlation signals in the form of binary level signals in response to the receipt by a last clock pulse detector of first and second store clock signals which are derived from first and second sampling clock signals. The time correlation signals indicate by their binary level the source of the last previous clock pulse of the first and second store clock signals which was received by the timebase correlation circuit.

Abstract: A resonant magnetic deflection circuit is disclosed for reducing a retrace period of an electron beam scanning within a cathode ray tube (CRT) apparatus. Opposite polarity flyback voltage pulses occur at both ends of a deflection coil. As a result, an effective retrace voltage appearing across the deflection coil is approximately doubled, thereby reducing the retrace period of the electron beam scanning within the CRT apparatus. One end of the deflection coil is connected to a reference level source through a first parallel circuit and an S-correction capacitor, the other end thereof being connected to the reference level source through a second parallel circuit. The first and second parallel circuits comprise switching devices, damper diodes and retrace capacitors. Moreover, both ends of the deflection coil are connected to a power supply through a flyback transformer.

Abstract: Apparatus for displaying a logic timing diagram on a raster scan type display device is disclosed. A logic signal is sampled and representations thereof stored in a RAM. The RAM contents are read repeatedly in synchronism with a raster scan operation, and the read-out signal is delayed by a predetermined time which is shorter than one bit cycle of the read-out signal. Logical gating functions, OR, exclusive-OR and NAND gates, receive the delayed and undelayed signals, and provide output signals from which the display of the "High" level, edges and "Low" level of the logic timing diagram are derived. Since it is not necessary to convert the logic signal to display codes and rewrite a display RAM, high speed scrolling and magnification can be obtained quickly and easily.

Abstract: An oscilloscope vertical calibration system is provided in which gain control elements in one or more vertical input channels are automatically controlled with respect to cursor voltages applied to the vertical output amplifier. Such calibration process is performed for each deflection factor setting either manually or automatically and the correct gain control signals are stored in memory.