Abstract: A joystick apparatus is disclosed having a minimum number of component parts associated therewith. The joystick apparatus comprises a first potentiometer, a second potentiometer, a bracket interconnected between the shafts of said first and second potentiometers, and a joystick connected to the base of one of the potentiometers. The bracket is interconnected between the shafts of the first and second potentiometers in a manner such that a movement of the joystick along one axis will impart a rotational movement to the shaft of one potentiometer, but will not impart a rotational movement to the shaft of the other potentiometer.

Abstract: A trigger circuit for use in an oscilloscope comprises a DC amplifier for low frequency amplification and high-frequency amplifier arranged to provide wideband trigger signal amplification while providing typical trigger coupling modes, such as AC, DC, high-frequency reject, and low-frequency reject.

Abstract: A circuit for providing a signal which is clamped to a desired DC voltage level comprises an amplifier for receiving an input signal and a feedback loop for developing an offset signal for combination with the input signal by the amplifier to provide an output signal at the desired DC voltage level. The feedback loop includes a noise detector for detecting the level of noise present in the output signal, and adjusting the time constant of the feedback loop in dependence thereon.

Abstract: A probe cable assembly for use in connecting a monitoring instrument to an electronic system under test comprises a sheet form cable having an instrument end, a probe end and an auxiliary interconnect end. A probe element having a plurality of terminals is secured to the cable at the probe end thereof and is capable of fitting in a multiple terminal receptacle of the system under test. An auxiliary receptacle capable of receiving a multiple terminal electronic component from the system under test and having a plurality of terminals is also secured to the cable. A first group of conductors of the cable extends between the instrument end of the cable and the auxiliary interconnect end and terminates at the auxiliary interconnect end in an array corresponding to the arrangement of the terminals of the auxiliary receptacle. A second group of conductors extends between the terminals of the auxiliary receptacle and corresponding terminals of said probe element.

Abstract: A restart circuit for a digital processor is disclosed. A regularly serviced processor signal is continuously monitored and if an intermittant soft failure of the processor occurs, causing the processor signal to go high or low or toggle in an irregular fashion, a restart pulse is automatically generated. Thus, with the occurrence of a soft failure, the operator no longer has to manually reset the processor system.

Abstract: A paper loading mechanism for a copier or the like is disclosed. A paper guide member and a foam pressure roller rotatably coupled to a paper drive roller feeds a web of paper to the drive roller, thereby semi-automatically feeding the paper along a predetermined path. A paper canister, having the webs of paper disposed therein, is affixed to a front cover of said paper loading mechanism. This structural arrangement simplifies the procedure of loading paper into the paper loading mechanism of the present invention.

Abstract: A resistor device comprises a first film of resistive material deposited on a dielectric substrate and having two terminal portions for connection to an electrical circuit, and a second film of resistive material deposited on the substrate in thermally-conductive contact with the first film and electrically isolated therefrom. The material of one of the films has a relatively high temperature coefficient of resistance, so that the resistance of that film can be utilized as an indication of the temperature of the other film.

Abstract: A waveform storage and display system particularly useful in digital oscilloscopes is provided in which successive waveforms of a repetitive signal are compared with a reference waveform, and upon detection of a difference or change within the waveform, the changed waveform is automatically stored. In addition to the conventional acquisition and display waveform memories, a reference-waveform and a changed-waveform memories are provided. Once a reference waveform is selected and stored, comparison of subsequent successive waveforms to detect changes is achieved under microprocessor control. Several display modes to provide a visual indication of changes may be implemented.

Abstract: A phase lock circuit including a phase/frequency detector, a plurality of selectable filters, and a plurality of variable frequency signal generators connected in a loop to lock an output signal to an input signal. An out-of-frequency-range condition detector is provided to facilitate automatic selection of an appropriate in-range combination of filter and signal generator to cause lock to occur.

Abstract: A method and apparatus is disclosed for independently displaying one of a plurality of images on a display and for superimposing the plurality of images onto one another to produce a composite image. One or more bit planes are selected to constitute a group (defined to be a "surface"), and one or more additional bit planes are selected to constitute another group. The number of groups corresponds to the number of images to be independently displayed. The priority of one group over the other is selected. This ensures that the image from the one group (surface) appears to be "in front of" the images from the other group (surface) on the display. In the case of a color terminal, the colors associated with each group are selected. A color map memory contains a plurality of brightness indices which determines image brightness. Associated with each index is one or more color indices.

Abstract: A special purpose pulse amplifier with programmable high and low levels for complex IC testing is disclosed. Its output has independently programmable positive and negative transition rates and is reverse terminated in 50 ohms. It also has the ability to be switched to a high resistance, low capacitance output state. This circuit is the interface between a complex, computer controlled system of timing and pattern generation hardware, and an integrated circuit to be tested. This device has reduced waveform aberrations, lower inhibited capacitance, low input to output delay for reducing timing error, programmable signal transition rates, and the amplitude range and transition rate control to accommodate all the important device technologies expected in high pin-count parts.

Abstract: A non-linear amplifier system comprises two amplifier stages, a limiter and correction stage and a combining stage. The first amplifier stage amplifies low input signal levels linearly and higher input signal levels non-linearly. The limiter and correction stage amplifies linearly input signal levels corresponding to low input signal levels of the first amplifier stage. The second amplifier stage amplifies non-linearly input signals corresponding to low input signal levels of the first amplifier stage. The combining stage combines the output voltage signals of the first and second amplifier stages and the limiter and correction stage.

Abstract: An electron beam deflection structure (10) of the traveling wave type includes first and second deflection members (52 and 58) positioned on opposite sides of and extending along the path of an electron beam (26) to deflect the beam in response to deflection signals applied to the deflection members. In a preferred embodiment, both deflection members are of a meander line type which include a plurality of deflection plate segments (74, 76) connected in series by a plurality of lead portions (78) to form a pair of transmission lines, each transmission line having a characteristic impedance that tends to vary with distance along the path of the electron beam due to a flared spacing between the output portions of the deflection members. Pitch compensation including different pitches for the first and second deflection members increases and maintains substantially uniform the characteristic impedance of each transmission line to prevent reflection of the deflection signal back toward the input end of the line.

Abstract: A compensation method and apparatus for a roughly compensated RC attenuator using fixed resistors and fixed capacitors. Any difference of the high frequency attenuation ratio from the low frequency of DC attenuation ratio is detected and corrected by using multiplier for increasing or decreasing high frequency components at the output from such RC attenuator, thereby allowing digital or remote compensation of RC attenuator without using variable capacitors.

Abstract: A magnet assembly comprises two pole pieces mounted so that their respective pole faces are in generally parallel spaced relationship. A mechanism applies force to one of the pole pieces at a location adjacent the pole face thereof and in direction transverse to the distance between the pole faces, whereby the pole piece that is acted upon is elastically strained and the relative orientation of the pole faces is altered accordingly.

Abstract: A recording material, comprising a hydrophobic substrate material with a polymeric coating, has excellent receptivity for inks that do not normally wet hydrophobic substrates. The substrate material is coated with a mixture of polyvinylpyrrolidone and a compatible matrix-forming polymer. The matrix-forming polymer is a material, such as gelatin or polyvinyl alcohol, that is swellable by water and insoluble at room temperature but soluble at elevated temperatures. A transparent base sheet, such as cellulose acetate or polyethylene terephthalate, can be coated with the mixture of polymers to provide a sheet material which can be used in ink jet printers and in pen-type graphics recorders, operating at normal speeds, to record large color-filled areas without puddling, running, or wetness and with high color density and excellent resolution.

Abstract: An automatic S correction circuit for a resonant scan deflection circuit comprises a plurality of S-shaping capacitors. The peak voltage and the peak-to-peak voltage across the S capacitors are detected, and the number of effective capacitors is varied to maintain the peak voltage and the peak-to-peak voltage in a predetermined relationship.

Abstract: A cathode and grid assembly includes a first grid of small diameter secured to a planar inner surface of a ceramic means and over a central opening in the ceramic means and a second grid having a first planar section secured to a planar outer surface of the ceramic means, a second planar section positioned within the central opening and a frustum of a cone section interconnecting the first and second planar sections with the frustum of a cone section extending along a frustum of a cone outer surface of the ceramic means.

Abstract: An image quality enhancement scheme is disclosed wherein the image information associated with each line of an image source is transferred to one line of an image receiving medium a plurality of times, the quality of the image information transferred to one line of the image receiving medium gradually improving following each subsequent transfer. A fiber optic cathode ray tube (CRT) transfers the image information to the image receiving medium. An electron beam generator in the CRT traces a plurality of scan lines on the inner faceplate of the CRT. The image receiving medium scrolls across the face of the CRT in synchronism with the trace of each of the scan lines on the inner faceplate thereof. The image information associated with each line of the image source is transferred to the one line of the image receiving medium via the trace of each of the plurality of scan lines.

Abstract: A trigger circuit including arm and trigger comparators which are responsive to the push-pull output from a differential amplifier but insensitive to its common mode component. A controllable hysteresis insertion circuit is also included in the circuit for noise rejection and sensitivity control purposes.