Abstract: A call charge allocation arrangement is implemented for a business communication system to track those situations in which a toll call is transferred from a first station to a second station. The arrangement tracks such transfers by establishing a first call record at the time the call is placed and establishing a second call record at the time the call is transferred, such that call charges which accrue prior to the transfer are entered in the first call record and call charges which accrue subsequent to the transfer are entered in the second call record.

Abstract: A time manager for a personal terminal can be generally characterized as a things-to-do file in which the user inputs a to-do reminder message along with a data and time that the terminal user wants to be alerted (reminded). The notion of a terminal time manager is advanced by displaying reminder messages directed to calling a named entity that is contained in the terminal telephone directory and by automatically calling the named entity when the user points to the displayed reminder. If the user inputs the actual telephone number to be called in place of the named entity, then the telephone number will be called even though the telephone number is not contained in the directory.

Abstract: The optical fiber connector of the present invention comprises a plurality of spaced-apart optical fiber receiving holes (or tubes) formed at one end of the connector and a spherical mirror formed at another end of the connector. The receiving holes are disposed on respective sides of the principal axis of the spherical mirror and the bottoms of the holes are collinear with and equidistant from the center of curvature of the mirror. Light signals emitted by an optical fiber inserted in one of the holes impinge on the mirror and are reflected in the direction of an optical fiber inserted in another one of the holes. The connector may be readily adapted to optically connect N+1 fibers together.

Abstract: A personal computer connected to a display and touch screen panel is provided with a form entry system integrated therewith. The form entry system is adapted to display a predefined form and to automatically display a predefined tool, such as a keyboard, menu, calculator, etc., to facilitate inputting information in a respective field of the form or chart. Specifically, the user is prompted as to which field is to be filled in by highlighting the field and concurrently displaying as an overlay (window) the tool that the user will use to input the information called for by the highlighted field. In the case where a field calls for illustratively the insertion of a name, the system may be adapted to display a menu of names as the tool for filling in that field. The user selects the name that he or she desired to be inserted in the field by touching that name. The system responsive thereto inserts the name in that field, highlights the next field to be filled in and displays the tool for filling that field.

Abstract: A sample clock signal generator is implemented to output a signal that is phase-synchronized with an external signal having a frequency that is significantly lower than that of the output signal. The output signal is obtained by generating a series of time-separated signals each having the desired frequency and selecting as the output signal that one of the series having a falling edge occurring after a predetermined transition of the external signal.

Abstract: The generation of individual moments of an image is advantageously achieved by generating a plurality of filtered signals in which each filtered signal is a linear combination of individual ones of the desired moments rather than the actual moment themselves. These filtered signals are obtained by passing the image signals through a series of single pole digital filters arranged as a matrix of filters. Each moment is formed at the end of an image frame by dematrixing the filtered signals. An illustrative embodiment uses repeating circuit patterns so that it can be easily integrated onto a circuit chip.

Abstract: An interface unit connected to one end of a communication path is arranged to conduct a transmission test of the path before exchanging information with an interface unit connected to the other end of the path and to signal the results of the test by terminating the test when the results show an absence of transmission errors and continuing the test when the results show the presence of such errors, the test being the transmission and reception of a predefined sequence of signals.

Abstract: A touch-sensitive device comprising a photoelastic screen having light reflecting edges and a unique light emitting/receiving module placed at two of the four corners of the screen advantageously determines the location at which a force is applied to the screen. Circularly and linearly polarized light focused into the photoelastic screen by the modules reflects off the edges of the screen and is returned to the modules where it is absorbed by a circular polarizer. The polarization of light passing through a point at which the screen is touched is changed thereby allowing these rays or signals to pass through each module's absorber. The location as well as the magnitude and direction of the force imparted to the screen by the touch is then determined from the changes in the signals that pass through the absorber.

Abstract: The sensitivity of an optically-based touch screen is substantially impro by adaptively establishing the detection threshold based on the peak trapped light measured over a number of frames on the screen being painted. In accordance with one feature of the invention, the peak trapped light from a target area painted on the screen is compared with a priorly established threshold as a way of determining that a target area is being touched by the user. In accordance with another feature of the invention, the threshold is modified in a way that compensates for possible erroneous touch indications due, for example, to bright spots on the screen.

Abstract: Circular paths in a multinode connection are avoided by passing an adaptive routing state, from node to node, which specifies the path options that the current node may use in its selection of a next step in the connection. The routing state, which is characterized by, for example, a single digit, is updated by the current node and is a function of the recent path history of the connection. The single-digit routing state controls the advancement of the connection by specifying whether the next selected step can be either a forward step, a null step or a backward step, or any combination thereof. A forward step advances the connection toward its destination, a null step does not advance the connection and a backward step causes the connection to step backward to a node not yet in the connected path. When a node selects a next step, it adapts the routing state digit to reflect its selection and passes the new routing state digit to the next node.

Abstract: A stored directory is searched from a display station set to obtain the telephone number of a sought-after name. The arrangement uses the station set keypad to generate signals corresponding to the spelling of the sought-after name. The arrangement adds each entry it receives to previously formed sequence of entries and, for each newly formed sequence, returns to the station set the name and telephone number contained in a directory record having a string of characters that compare to the newly formed sequence. The arrangement also provides means for scrolling through the directory.

Abstract: In order to cool heat generating components on an electronic assembly without contamination by particles carried in a cooling gas stream, a cold plate is disposed adjacent the assembly, defining a gap region therebetween. The cooling gas is directed in proximity to the cold plate, dissipating heat transferred from the components to the plate. To enhance overall heat dissipation of the apparatus, an aperture is defined between the gap region and the gas stream, so that a negative pressure is induced in the gap by virtue of the Bernoulli principle. This pressure difference induces convection within the gap, increasing heat flow between the components and the plate, and resulting in overall improvement in heat dissipation. Embodiments in which the gas stream flow is parallel and transverse to the cold plate are described.

Abstract: A transient power alarm is often the result of a traffic overload placed on a communication system circuit carrier circuit. The disclosed power control arrangement recognizes such transient power alarms and outputs a special message to alert the system user to the possibility that traffic grading across carrier is unbalanced. The control arrangement also monitors the time that the system is powered solely by reserve battery and sheds its traffic load if the time that the system is operating solely on reserve battery exceeds a first threshold. Also, the system is programmed to automatically disable itself if the reserve battery time exceeds a second threshold.

Abstract: There is disclosed a multifrequency tone distribution arrangement for a communication system having a common time division multiplexed bus in which digital samples of tone frequencies are supplied from a central signal generating circuit to system port circuits via selected time slots. Each port circuit automatically accepts selected signals from the common bus for conferencing to produce multifrequency digit tones and service tones.

Abstract: The disclosed arrangement of digital signal processor and echo cancellor is connectable to four wire transmission facilities on a per port basis for providing adaptive signal conditioning to reduce noise and improve level contrast among conferees of a digital conference connection. The digital signal processor applies an adaptive gain value to incoming speech signals for either increasing or decreasing the level of these signals to meet a predetermined threshold. A fixed gain adjustment is applied to incoming noise signals to reduce the level of these signals. The arrangement also provides a last-talker holdover mode in which the last gain adjustment applied to last-talker speech is applied to idle channel noise on that line.

Abstract: There is disclosed a control channel interface circuit for interfacing a port processor of a distributed multiprocessor communication system to a common time division multiplexed bus. The detection, extraction and synchronization of control messages passed between a central processor and port processor via a TDM bus are handled by the interface unit thereby relieving a port processor of this burden. A group of control time slots within a system frame are dedicated for the transfer of control messages between port processors and a central processor. The interface unit also monitors the operability of a respective port processor and automatically disables a faulty processor.

Abstract: There is disclosed a circuit pack carrier molded as a single structure having an ample draft angle between the circuit pack guides to facilitate removal of the circuit pack carrier from the mold. The guides are cantilevered from the front and arranged into groups and a backplane board connected to molded alignment pins brings the circuit pack guides into parallel alignment. A slight inward flexure of the circuit pack guides is created for firmly gripping and holding in place inserted circuit packs. The unitary constructed carrier has special molded-in side wall channels for easily mounting the carrier to a frame or cabinet.

Abstract: There is disclosed a precision linear comparator for a speakerphone circuit having two rectifying constant voltage nodes for separately summing two groups of signals derived from a speakerphone transmit channel and receive channel and supplying at an output terminal a signal representative of the difference between two unblocked summed signals. Each node blocks its summed signal if the signal is not representative of a true voice signal. A null signal is supplied at the output terminal during the absence of unblocked summed signals.

Abstract: There is disclosed a speakerphone circuit employing precision peak detectors in which the processing of talk down signals and switch guard signals is partitioned in order to accurately control complementary switched gain in the transmit and receive channels to achieve improved sensitivity to talk down switching action by setting a low switching threshold.