Abstract: A digital oscilloscope includes an acquisition system for digitizing an input signal to produce and store in memory a waveform data sequence representing the input signal. A display system within the instrument reads out and processes the data stored in the memory to produce a waveform display representing the input signal. The instrument responds to an input "erase" command from a user by overwriting the waveform data sequence stored in memory with a predetermined data sequence defining an easily recognizable display pattern. The oscilloscope thereafter performs a checksum operation on overwritten portions of memory to determine whether the overwrite operation was successful, and displays an indication of overwrite success on its screen.

Abstract: A method for increasing the resolution of measurements taken using a counter-timer is provided that includes the steps of selecting a magnifier value and displaying the selected magnifier value on a CRT screen, performing a trial measurement with the counter-timer set at a fixed gate time and displaying the trial measurement result, calculating a new gate time from the magnifier value and trail measurement results, displaying the new gate time, and performing a second measurement with the counter-timer set to the new gate time and displaying the second measurement result.

Abstract: An optical pigtail assembly is described wherein the focusing lens through which the laser diode output passes has its planar surface facing the laser instead of its convex surface. This configuration provides greater coupling efficiency when launching 850 nm light from the laser into an optical fiber. In the method of manufacturing the optical pigtail assembly, ultraviolet, UV, cured epoxy is used to bond the elements of the pigtail assembly together. The use of UV cured epoxy overcomes environmental problems and high capital equipment costs associated with other types of laser pigtail assembly manufacturing methods.

Abstract: An ink jet print head face cleaner provides a controlled air passageway through an enclosure formed against the print face. Air is directed through an inlet into a cavity in a body. The body has a face with an opening into the cavity. This face is sealingly placeable against the print face. The cavity has a limited size so that air is directed without interruption through the cavity past the ink jet apertures, and out an outlet. The cleaner body is coupled resiliently to a platform to allow positioning of the body and print faces flush with each other. A vacuum source is preferably attached to the outlet to create a subatmospheric pressure in the cavity to further seal the two faces together. A collection chamber and removable drawer are positioned below the outlet to facilitate disposing of removed ink.

Abstract: A circuit allows digital data acquisition instruments to recognize when dual threshold synchronous data being monitored in unstable. Each data line being monitored for unstable periods is compared with a high threshold level and a low threshold level at an acquisition probe and the results of these two comparisons are forwarded to the circuit of the present invention. Optionally, a glitch latch may be employed to cause transient crossings of the threshold to be treated as if they lasted until the next clock. The two bits of resulting information are each clocked through a short shift register consisting of two flip-flops. A gate monitoring each of these short shift registers produces an active output when the state of the two flip-flops indicates that the signal left the high state or left the low state. A third gate monitors the last flip-flop in each short register to produce an active output when the signal is neither high nor low.

Abstract: An inductor and carrier suitable for mounting on a mounting substrate includes an etched sheet of a bonded copper layer and polyimide film to form a film carrier. The periphery of the film carrier is patterned with a plurality of windows and a plurality of conductors, each conductor having a bent-up tab and and end portion terminating at the periphery within the respective window. A microminiature inductor core having a plurality of insulated windings is soldered to the respective bent-up tab of each conductor and the end portion of each conductor is then welded to bonding pads on the mounting substrate.

Abstract: A serial-parallel-serial, charged-coupled device includes an array of horizontal rows and columns of closely spaced charge storage cells. Each storage cell is formed by an electrode covering an insulation layer above a semiconductor substrate. The semiconductor substrate of each storage cell includes a channel region for conducting carriers laterally through the storage cell. The channel region of each storage cell included both in a first row of the array and in any column of the array has a tilted potential gradient providing an electric field facilitating charge carrier drift within the channel region in two lateral directions, toward a neighboring storage cell of the first row and also toward a neighboring storage cell of its column.

Abstract: Apparatus suitable for on-wafer probing of microwave integrated circuits includes a coplanar waveguide carried on one surface of an elongate, tapered, dielectric substrate. The waveguide includes a signal conductor extending substantially the length of the substrate and a pair of ground conductors extending along the opposite edges of the signal conductor. The substrate is bonded to a metal mounting block adjacent one end of an coaxial electrical connector. Conductive bonding material, suitably a conductive epoxy material, is applied along the outer edges of the ground conductors to establish a low impedance ground path between the coaxial waveguide and the metal block.

Abstract: A probe includes a flexible sheet of dielectric material having an opening therein sized and shaped to receive an electronic component mounted on a support member at a major surface thereof, a contact pad exposed at a first main face of the sheet and adjacent the opening therein, and a conductor connecting the contact pad to a terminal of the probe. The probe is positioned with its first main face in confronting relationship with the major surface of the support member and with the opening in the sheet in registration with the electronic component, and pressure is applied to the flexible sheet to bring the contact pad into contact with the test point.

Abstract: A method for timing audio and video component signals of a television signal with coincidental markers generates a field pulse every Nth field of the televison signal at the transmitter. The duration of the field pulse is approximately one video field, and is ued to enable an audio tone generator for the one video field and to switch a distinctive video signal, such as a flat video signal, into the video component signal for the one video field. At the receiver the two component signals are input through a synchronizer to a waveform display device, such as an oscilloscope, to observe the time differential between the two markers in the audio and video component signals. The audio component signal is delayed by the synchronizer until the markers are again in time conicidence as at the transmitter.

Abstract: A multi-purpose display module system for an electrical instrument has a readily detachable display module for remote use that can be quickly reattached. The display module is readily adjusted in tilt angle, whether attached or remoted. A front frame with a recess is mounted on the front of a main chassis for the instrument. Latches are mounted on the main chassis and extend into the recess on opposite sides of the recess, the ends of the latches defining a rotation axis across the recess. A display module has clutch assemblies frictionally, rotatably mounted on opposing sides to fixedly engage the ends of the latches when the display module is mounted within the recess. Release of one latch allows the display module to be removed and set up independently with a stand integral with the clutch assemblies, the display module being electrically connected to the electrical instrument by an electrical cable of suitable length.

Abstract: A method of detecting a splice in an optical fiber in the presence of noise generates a nulling filter from a segment of a signal received from the optical filter by determining a set of coefficients having an initial "1" followed by p-1 "0" values and w.sub.i finite impulse response filter values, where p is a prediction interval greater than the width of an expected splice signature. The received signal is processed by the nulling filter to remove exponentials from the received signal, leaving an error signal containing noise and splice information. The resulting error signal is processed by a correlation filter to reduce the noise in the error signal. The output from the correlation filter results in a noise reduced error signal with the splice appearing as a noticeable dip in the waveform. The waveform is passed through a threshold detector to identify the splice when the dip exceeds a predetermined threshold.

Abstract: A contact element is formed on a sheet of dielectric material by depositing conductive material in an opening in a first layer of dielectric material, and depositing a second layer of dielectric material over the first layer and over the conductive material in the opening. Material of the first layer is removed from the surface farther from the second layer so that the conductive material projects beyond the first layer.

Abstract: An apparatus and method for calibrating an interleaved digitizer includes a system oscillator for generating a master clock signal and two or more cascaded phase shifting circuits for producing clock signals that are phase shifted copies of the master clock signal. The calibrator further includes two or more A/D converters for digitizing the master clock signal at time intervals provided by the phase shifted clock signals to produce a digitized output. The digitized output is then stored in a memory. Once stored, the digitized output is compared to predetermined reference levels and the phase shift of the phase shifting circuits is appropriately adjusted as a function of the difference between the stored digitized output and the predetermined reference levels.

Abstract: A sintered body of indium tin oxide is fabricated by forming a finely divided mixture of indium oxide, tin oxide, aluminum oxide and silicon dioxide, compacting the mixture, and heating the mixture to a sintering temperature.

Abstract: An apparatus providing a substantially fixed length cable drive comprises a motor-driven capstan having a helical groove. The groove on the capstan is sized to receive opposite ends of a cable for simultaneously letting out and taking up the cable. The cable passes over a fixed pulley and is attached to a carriage at a point intermediate the capstan and pulley. The carriage is guided along a rail defining a fixed mass path. The section of cable between the carriage and pulley is parallel to the mass path. The cable ends on the capstan are disposed on opposite sides of a plane containing the parallel cable section during travel of the carriage along the mass path.

Abstract: An arbitrary waveform generator using packet data words to represent segments of a desired complex waveform includes a variable clock. Each packet data word contains a clock control word that is used to control the variable clock frequency so that the duration of each segment is adjusted to produce the desired complex waveform.

Abstract: A dispenser cathode body includes a heat capturing portion extending rearwardly from the dispenser cathode, said heat capturing portion having greater mass and thickness than an exterior support skirt. A slip-in heater is received within the heat capturing portion. Substantially greater electron emission density is secured without requiring injuriously high temperatures from the slip-in heater.

Abstract: A data transfer driver transfers multiple byte data words supplied by a data processing device to a peripheral device as a sequence of single data bytes. The driver operates selectively in either a handshaking mode, wherein data bytes are transferred to the peripheral device asynchronously in response to handshaking signals from the peripheral device, or in a streaming mode where data bytes are transferred to the peripheral device periodically. The driver includes circuitry that permits the data processing device to check the operation of the driver and to monitor handshaking signals produced by the peripheral device.

Abstract: A trackball-type input device (10) uses a retainer (114) to secure a ball (80) to a housing (12) so that a large segment (164) of the ball (80) protrudes from the housing (12) for manipulation by the user, thereby affording precise control over rotational movement of the ball (80).