Abstract: A quad-T transformer in some embodiments includes a first split winding, a second split winding, and two orthogonal closed-loop windings coupled between the first split winding and the second split winding. Wires can be wound around magnetic cores. A first of the two orthogonal closed-loop windings is coupled to a first portion of each of the first split winding and the second split winding. A second of the two orthogonal closed-loop windings is coupled to a second portion of each of the first split winding and the second split winding. A bi-directional single-phase/three-phase converter includes the quad-T transformer and a Scott-T transformer with an output connected to a three-phase connection. The Scott-T transformer also has a 90-degree input connected to the quad-T transformer and a zero-degree input connected to a single-phase connection.

Abstract: A marker generating method is provided for facilitating the finding of positions which correspond to one another among a plurality of images associated with a video signal. A position within an image (800) associated with a video signal is selected, with a cursor (802, 804) to display a marker (812, 822-826) at a position corresponding to the selected position, in a different image (810, 820) associated with the video signal.

Abstract: In a low voltage differential-mode signaling (LVDS) test system and method, a positive signal waveform and a negative signal waveform of an LVDS signal pair are obtained. A differential-mode high voltage, a differential-mode low voltage, and a common-mode noise are measured according to the positive signal waveform and the negative signal waveform. The measurement results are output to an output device.

Abstract: Differences in outputs from multiple terminals are easily measured.

Abstract: A method for detecting a failure in a radio frequency (RF) device (200) that includes a transistor (210) having a first terminal at an RF input (220), a second terminal at an RF output (260), and a third terminal at an RF common (230). The method includes the steps of: detecting a first voltage at the first terminal; comparing the first voltage to a reference voltage; and determining whether the RF transistor (210) is operating in a normal state or a failed state as a function of whether the first voltage falls inside or outside of a predetermined threshold value of the reference voltage.

Abstract: An oscilloscope apparatus and method of processing waveform data using a streaming architecture. The apparatus has multiple processing objects (processors) that share a common cache memory in which the waveform data is stored during processing. Each processing object performs a sequential processing operation by retrieving a “chunk” or portion of the waveform from the memory, processes the chunk of data, and re-stores the processed data into the same location in the cache memory. This process is generally repeated until the entire waveform has been sequentially processed. The apparatus operates using a “pull” design wherein the last processor requests the next chunk to be processed from the preceding processor. In this manner, the waveform data is essentially processed by pulling it through the sequence of processing objects. The multiple processing objects may be implemented as a sequence of software processing objects in a processing thread or as separate hardware processors.

Abstract: A raster scan digital signal acquisition and waveform display instrument displays a dot representing a signal event with a color parameter in accordance with the value of a corresponding data word stored in a raster scan memory. A user interface control element supplies a single color parameter control value from which multiple independent control values for influencing the values of the data words stored in the raster scan memory in response to the single color parameter control value are generated.

Abstract: A device to assist in setting up the pitch, roll, yaw and standoff of a read head relative to a scale, so as to improve the quadrature relationship of its outputs. Two superimposed Lissajous figures are produced on an oscilloscope screen. One of these figures is a rotation or reflection of the other. The read head is adjusted until the Lissajous figures coincide. Simpler, less accurate arrangements are also described, in which a variable DC output signal is produced which represents the radius of a hypothetical Lissajous derivable from the signals. The read head is then adjusted to give a constant DC output, representing a constant Lissajous radius.

Abstract: The relative gain and/or delay of two signal transmission channels may be measured by impressing on each channel a repetitive signal comprising a burst packet. The burst packets of the signals applied to the channels are of constant, but different, frequencies, and their amplitudes are related in predetermined manner. The two burst packets are timed to have a predetermined phase relationship at a selected time during the packets. The output signals of the two channels are additively combined, and a determination is made as to at least one of (a) the amplitude of the combined signal at a turning point in the amplitude of the signal envelope and (b) the time relative to the selected time at which a turning point in the amplitude of the signal envelope occurs.

Abstract: Apparatus for displaying in polar coordinates the relative phase and amplitude of a chrominance signal comprises a display device, such as a CRT display device, having a circuit for adjusting the brightness of the light dot. The apparatus also comprises a circuit for generating a blanking signal and applying it to the adjustment circuit in the event that the amplitude of the chrominance signal is below a predetermined value.

Abstract: An apparatus is disclosed which provides a display of the stereo image and aural perspective of stereophonic sounds. Left and right signal are processed to form rectified sum and difference signals which are applied to the signals which are applied to the vertical and horizontal deflection electrodes of an oscilloscope.

Abstract: Apparatus for indicating the timing relationship between a reference point of a repetitive input signal, e.g. the horizontal sync point of a video signal, and a signal element that repeats at a higher frequency than the input signal, e.g. an element of the color burst, comprises a phase-locked oscillator for generating a continuous wave signal that is in phase with the signal element. The continuous wave signal is used to generate a train of pulses having a repetition frequency that is equal to the repetition frequency of the signal element and is selectively variable in phase relative to the continuous wave signal, and this train of pulses is used to modulate a display of the repetitive input signal in a dimension other than one that is used in a normal waveform display, e.g. intensity.

Abstract: A waveform monitor for television has dual video channels displayed simultaneously side-by-side. The two channels are synchronized with each other or with an external sync signal and are input to a multiplexer prior to the display. A microprocessor controls the switching of the multiplexer according to the selection made by an operator. The first channel is displayed during the first half of the horizontal display sweep, and the second channel is displayed during the second half, the horizontal sweep encompassing two horizontal lines of video.

Abstract: A visual indication of the relationship between first and second electrical signals, such as the left and right channel signals in a stereophonic audio system, is provided through use of a video vectorscope. The first and second signals are used to modulate the amplitude of two sinusoidal waves at a subcarrier frequency and in phase quadrature, so as to synthesize the chrominance portion of a composite video signal. The two modulated sine waves are additively combined, and the resulting signal is applied to the input terminal of the vectorscope.

Abstract: Graphics display systems ideally suited for the display of certain types of graphics information are disclosed. The display systems utilize a black and white or color raster scan display having a vertical rather than a conventional horizontal raster scan. Data stored in the refresh memory of the display system is run length encoded so that a display pixel may be defined at any position along each vertical sweep of the raster scan or trace. Multiple channels allow the definition of multiple pixels on each scan, which allows the display of graph type data in a manner simulating the output of a multiple channel strip chart recorder. The system includes alphanumeric character generation and graphics character capabilities which allow the definition of grid lines and the labeling of information displayed.

Abstract: In a method and a vector scope for measuring distortion of a subcarrier signal causing color aberration of a color television signal, a carrier chrominance signal resulting from a color bar signal transmitted in a transmission system and a reference carrier chrominance signal including a signal determining levels of the amplitude and phase distortions of said carrier chrominance signal are demodulated through the same demodulating device and color difference signals thus obtained are displayed in vector, whereby only the distortion of the subcarrier by the transmission system is measured independently of the influence of the distortion of the vector scope itself.

Abstract: A method and apparatus for detecting the point of contact between a workpiece of electrically conductive material in a machine and an electrically conductive element movable relative to and insulated from the workpiece, such as the electrode of an electrical discharge machine, wherein in a time-varying signal, in particular sinusoidal, of predetermined amplitude and frequency is applied to the workpiece, a signal is derived from the conductive element or electrode resulting from the flow of current through the gap between the workpiece and conductive element in response to the applied signal, and the applied and derived signals are compared as to amplitude and phase angle. An indication of the comparison is provided with the result that the combination of an amplitude difference and a phase difference between the applied and derived signals indicates the status of the contact gap, respectively, between the workpiece and conductive element or electrode.

Abstract: A digital video analyzer apparatus which provides in a single enclosure, waveform displays, composite video line displays, differential gain/differential phase displays, and vector displays, for a number of different video input signals, the apparatus being capable of displaying the above signals for at least one full horizontal line as selected by the user, and, for a waveform display for at least a full field.

Abstract: A process and two embodiments of an apparatus are disclosed for displaying, on the screen of a conventional home television receiver, curves illustrating analog signal potential functions of the form U(x,y). The process generally requires generating first and second saw-tooth signals synchronized with the vertical and horizontal sync. signals of the picture raster of the home television receiver. At least part of each of the signal potentials U.sub.y and U.sub.x are then compared with the first and second saw-tooth signals to generate first and second impulse signals respectively when equal potential conditions are observed. The first impulse signal is then differentiated with respect to time to form a gate impulse signal of adjustable width for controlling the processing of signal potential U.sub.x. The second impulse signal is differentiated with respect to time to form a brightness control signal for output to the home television receiver.

Abstract: Apparatus for monitoring and controlling the operation of a dual platen press used in the manufacture of nuclear fuel pellets is disclosed. The apparatus includes means for indicating the displacements of both platens and imposing the displacements of the platens on orthogonal axes such that the displacements jointly control the motion of a point which traces a lissajous figure representative of the displacement and relative velocity of the press platens. A second lissajous figure representing the desired platen movements and relative velocity may be superimposed on the first lissajous figure, differences between the first and second lissajous figures indicating deviations from the desired operation of the press. Alternately, a press operator may simply use the first lissajous figure constructed from the actual platen displacements to analyze the operation of the press. The completion of preselected portions of the first lissajous figure may be detected and used to trigger subsequent press operations.

Abstract: This invention concerns a circuit arrangement for visually representing a horizontal frequency coupled input signal on the picture screen of a video display device such as a domestic television receiver. This is achieved by comparing the input signal to be represented in visual form with a vertical frequency sawtooth signal, the comparison being effected in such manner that a further signal is produced which identifies the moments when the two compared signals are equal. The further signal is then used directly or indirectly to control the brightness of the picture screen of the video display device.The further signal may be a pulse form signal with the leading flanks of the pulses corresponding to moments when the input signal crosses the sawtooth signal upwardly and the trailing flanks corresponding to the moments when the input signal crosses the sawtooth signal downwardly. The further signal is preferably differentiated prior to application to the display device.

Abstract: In an illustrated embodiment an analog signal is sampled by means of a bucket brigade store. The stored samples are then repeatedly cycled through the store during refreshment of a visual display via a controlled amplifier. The storer also receives a reference voltage sample which is also circulated and which is periodically sampled at the storer output and compared with the input reference voltage, any deviation being utilized to control the amplification of the amplifier to maintain the reference voltage sample at substantially a constant level, and thus to maintain essentially unity amplification during the cyclical operation of the storer. The reference voltage sample can be selectively obtained from the measured signal or by means of a separate reference voltage generator. In the latter instance, the reference voltage sample is to be blocked so as to avoid display thereof, a previous sample of the measuring signal, for example, being displayed instead.

Abstract: A slewed-pulse display is provided for calibrating the time-base axis of an oscilloscope. In a repetitive-sweep display, the leading edges of incrementally delayed successive pulses are slewed across the display screen. Timing and linearity adjustments may be made in the time-base generator circuits so that a leading edge of a pulse is aligned with each vertically scribed graticule line overlaying the display area.

Abstract: An oscillographic display of at least one input signal which is of arbitrary period or is aperiodic may be generated upon a standard television receiver by storing the input signal in a storage medium containing a multiplicity of storage elements and triggering the storage in synchronism with the input signal. The rate of storage of the input signal is controlled independent of the input signal rate. The stored input signal is thereafter read out at a time rate synchronized to the horizontal synchronization frequency of the television receiver and converted into compatible video signals for display. Adjustment of the rate of storage of the input signal provides a corresponding change in time scale in the displayed input signal. Color labeling and a background color is provided as well as a graticule.

Abstract: Apparatus for measuring the frequency of a reference signal which utilizes he color subcarrier signal of a television receiver as a standard frequency signal. In a first embodiment, the reference signal controls a circuit to develop bursts of a synthesized color subcarrier signal, gated at the horizontal line rate of a color television receiver. The synthesized signal is superimposed on the broadcast television signal and applied to the receiver to produce a modulation bar on the screen. Any frequency/phase difference between synthesized and broadcast color subcarrier signals will cause the modulation bar to move laterally across the screen, and/or cause the sequence of colors within the modulation bar to vary. Movement of the modulation bar is a coarse indication of frequency difference and change of the color sequence within the bar is a precise indication of phase difference.