Abstract: A time stamping method for threshold crossing points of an input signal uses a dithered threshold level. Digital data samples are acquired for the input signal and time marks are determined for the threshold crossings using interpolation. The time marks are stores as the time stamps. A threshold offset value generator generates a distribution of offset values for dithering the threshold value. Time interval values are generated from the time stamps and the number of occurrences of time interval values are accumulated in time bins. A time interval distribution histogram and statistical time interval distribution data, such as the mean, standard deviation and minimum and maximum time intervals may be generated.

Abstract: A system for producing a signal representing an envelope waveform corresponding to the minimum and maximum excursions of an underlying signal includes a source of the underlying signal and a signal acquisition circuit coupled to the underlying signal source. A circuit for calculating the envelope of the underlying signal is coupled to the signal acquisition circuit to produce an envelope signal. A rasterizer, coupled to the signal acquisition circuit and to the envelope calculating circuit, generates the envelope waveform representative signal being a single raster displaying waveforms representing the envelope signal and the underlying signal.

Abstract: A monitoring OAM (operation administrating monitoring) cell assisted method to detect bit errors occurring in ATM useful cells on an ATM transmission link generates first control bits by evaluating bits of ATM useful cells with a selected target address in the cell head prior to feeding the ATM useful cells into the ATM transmission link, whereupon the first control bits are Abramson-encoded to generate further, second control bits. The first control bits are additionally encoded to produce additional, third control bits, all of which are entered into the monitoring OAM cells and transmitted on the ATM transmission link with the ATM useful cells. At a receiver decoder the ATM useful cells are separated from the monitoring OAM cells, the monitoring OAM cells are error detected and corrected where necessary using the second and/or third control bits to provide error-free OAM cells, the first control bits of which are used to detect bit errors in the ATM useful cells.

Abstract: A thermal transfer color printer (100) utilizes a single print head (102) positioned outside a carousel (104) of monochrome ink ribbons (106) each stretched between a pair of spaced-apart spools (108, 110) mounted around the periphery of the carousel. A spool spacing (112) provides sufficient clearance for the thermal print head to be positioned between to spools to contact the ribbon. A media drum (116) is positioned coaxially within the carousel. The carousel has a media opening (122) through which a print medium (118) enters and exits a medium clamp (144) attached to the media drum. To print a particular color, the carousel is rotated such that the media opening is adjacent to a media supply, and a print medium is guided from the media supply into the medium clamp. The media drum is rotated to close the medium clamp and position a leading edge (138) of the print medium adjacent to the print head.

Abstract: A testing method and apparatus employs electron beam writing and reading of conductive paths in a circuit device rather than physical probing of conductive elements. Portions of the circuit device, e.g., conductive paths, are bistably stored at a given potential and then the device is read by a reading beam to determine if proper connections exist. Read out is at comparatively high levels represented by the difference between bistable voltage values. Once a portion of the device has been tested, it may remain in stored condition such that additional cross checking or repetition of testing is rendered unnecessary.

Abstract: An electronic system is disclosed which examines the first derivative of an applied electrocardiographic (ECG) signal, recognizes the R-wave event therefrom, and discriminates against signal components which lie outside predetermined signal parameters in producing a rectangular pulse output. In addition, muscle artifact and pacers are discriminated against. The system includes an automatic gain control to eliminate the need for operator controls.