Abstract: A data acquisition circuit is disclosed which provides sampled input voltage signals generated in a hostile environment to an input device, for example, the input circuitry of a computer. The data acquisition circuit provides electrical isolation to prevent damage to the input circuitry caused by electrical transients and short circuits occurring in the hostile environment and is particularly useful for sampling input data from thermocouples because it eliminates the need for an isolated power supply normally used to detect broken thermocouples.

Abstract: A double loop transmission system is provided in which not only bypass routes but also terminals are connected with a pair of transmission control units of each loop. In this manner, the transfer of a message is controlled by both the information concerning whether the smaller loop formed by a pair of the adjacent transmission control units is abnormal or not and the bypass code data contained in the message. The transmission can thus be continued no matter which loop has its transmission control units disordered. And the transmission between the terminals can be performed by the construction and reconstruction of the bypass routes when a loop which has been disordered is restored.

Abstract: In a communication network comprising block switching nodes interconnected by transmission links, a flow control mechanism is provided in each switching node for regulating the flow of addressed data blocks or messages. A hardware look-ahead mechanism effective within each node tests for each data block received from a link and buffered at an input port, whether it can be accepted at the appropriate output port of the same node for further transmission. A token mechanism effective over links permits maintenance at each output port of a node of an indication whether any data block can be accepted in the input port at the other end of the respective link. By the combined operation of look-ahead mechanisms and token mechanisms the flow of addressed messages in a direction where the transmission path is already filled up is prevented. This has a positive smoothing effect on overall traffic flow where short-time or local overloads occur.

Abstract: A low-pass filter passes a spectrum of electrical signals which are utilized to establish a threshold level with which electrical signals having frequencies in a relatively higher range are compared to determine if a warning sound is present in the sounds in the vicinity of a receiver unit for receiving the ambient sound. If the rectified magnitude of the signals having the higher frequencies exceeds the rectified and variably adjusted magnitudes of the signals having lower frequencies, a visual indication is given to communicate the existence of a warning sound in the ambient sounds.

Abstract: The proximity switch has a capacitive sensor which comprises a metallic support mounted on a printed circuit board and supporting, on a surface parallel to said board but facing away from it, a layer made of electrically conductive foam material. The latter nestles against a cover plate made of glass which provides the dielectric of a capacitive sensor actuatable by the stray field of the mains. When this alternating stray field is concentrated by a part of a human body brought into the vicinity of the sensor, the latter will actuate an electronic switch connected to it.

Abstract: An electromechanical interactive terminal system is disclosed, utilizing a split keyboard to accommodate convenient use, even by disabled or infirm persons. The elements of a conventional typewriter (or console) keyboard are provided in two separate and distinct keyboard units, one of which includes the keys normally activated by the right hand while the other has the keys conventionally assigned for use by the left hand. Control and coding keys are similarly assigned. The two separate keyboard units can be used in various positions as by being affixed to a support member so as to be held in spaced-apart relationship, contiguous to the hands of an operator with his arms apart and supported at rest. The keyboard units each incorporate electrical apparatus for providing electrical signals representative of data symbols associated with the keys. Additionally, certain keys are coded to provide control signals used in association with display means, a data processor, and a printer.

Abstract: Apparatus is disclosed for generating a signal representative of a co-ordinate position of a movable indicating member, the member being constructed for interacting magnetically with sensing coils. The apparatus includes a plurality of sensing coils (2 to 11) for interacting magnetically with such a member, the coils being positioned substantially in or adjacent to a real or imaginary surface in or adjacent to which such an indicating member may be moved, the sensing coils being positioned to divide an area of interest in the surface into regions, each of the coils encircling part of the area of interest and having conductors in the area substantially along region boundaries only, each of the regions being within an arrangement of the sensing coils particular to that region. A further coil (1) is positioned substantially in or adjacent to the real or imaginary surface and surrounds the entire area of interest.

Abstract: Apparatus for producing updated information on a tangible medium including a hand-held type instrument having an optical character reader to read present information on the medium, a programmable bus-oriented computing type network, spaced from the instrument, which stores and compares the updated information with the present information being read and which outputs control words corresponding to the updated information if the updated information is different from the present information, and an ink jet printer, included in the hand-held type instrument, which prints the updated information on the medium in response to the control words. The computing type network can include a micro-computing unit which can be a microprocessor, for example, and memory units which can be RAM, ROM, etc.

Abstract: A system for monitoring the internal conditions in a rotary kiln is disclosed wherein a series of sensors, such as thermocouples, are installed in ports at various longitudinal and angular coordinates along the total length of the kiln for providing temperature signal samples in the form of sequenced millivolt signals, and a single thermocouple is provided which is insertable in a second series of ports along the kiln to permit immediate localized temperature sensing. The sequenced millivolt signals and the single thermocouple millivolt signals are both fed to respective millivolt-to-milliamp converters mounted on a heat shield on the kiln surface, which shield also mounts two sets of continuous slip rings encircling the kiln. The respective milliamp signals are communicated from the converters to the respective slip ring sets from which they are picked off by suitable stationary contact means disposed adjacent the kiln and conducted to appropriate recorders in a control room.

Abstract: A transparent intelligent communication network having nodes and communication links between the nodes and providing improved system input features by including the sampling of customer inputs at different rates according to their output rates of data at the exit node or at faster rates if there is a spare channel capacity available.

Abstract: A marker channel telemetry system for use with a pacemaker or other medical device for transmitting event identifying codes to a remote receiver to indicate the occurrence of specific events such as sensed and paced events in a dual chamber pacemaker. The structure of the system includes latches to store event information and for forming the marker codes. The system also includes a serial telemetry transmitter for transmitting the data to the remote receiver.

Abstract: A rotational shaft home position sensing transducer is provided which comprises a rotor mounted on the shaft having a planar surface with a first radial array of conductive elements on the surface in combination with a fixedly mounted stator having a planar surface parallel to the planar rotor surface and a second corresponding radial array of conductive elements on the stator surface adjacent and spaced from the first array. The structure further contains a unit for applying an alternating electrical signal to the first array of elements and a unit connected to the second array of elements for sensing the capacitive effect induced in the second array by said electrical signal. The first and second arrays must be arranged so that a single home position in the relative motion between the rotor and stator will induce a single unique capacitive effect in the second plurality of elements.

Abstract: A decoupling arrangement for non-insulated track circuits is disclosed wherein the receiving circuit of the evaluating unit for the AC track currents is electrically separated from the traction-current-carrying parts of the track. The cross bonds between the two rails of a track may be shorting bonds or so-called S bonds. The arrangement according to the invention improves the tuning behavior of the track circuit receivers considerably.

Abstract: A photoelectric circuit for reading punched data tape wherein the circuit compensates for variations in phototransistors and light emitting diodes, dust accumulation and degradation of the light emitting diodes by comparing the light transmitted through a punched section of the tape to the light transmitted through a solid section of the tape.

Abstract: A line test termination device to provide a characteristic signature recognizable by the telephone central office when a continuity test is made on a subscriber line having a pair of electrically conductive paths includes a resistor and a diode connected in series between the conductive paths. A neon tube device placed in series with the resistor and diode will be illuminated when a ringing voltage is applied to the line and no telephone ringing circuit is connected thereto.

Abstract: A method is disclosed for automatically detecting a trunk that is likely to be defective even though it passes operational tests incident to switching it into service. In a telephone system, such a trunk might, for example, be so noisy or ineffective for transmission that customers cannot communicate over that trunk. Resultingly, the trunk is likely to handle a much higher than normal number of calls with short holding times since the customers quickly discover that they cannot communicate and terminate the calls. The method is implemented via telephone call processing, memory lists, and a program routine integrated into the call disconnect sequences. It allows such defective trunks to be identified by the steps of: detecting all calls with short holding times, successively processing trunk identities which have a repetition of such short holding-time calls, and alerting the maintenance force when such trunks have been processed through several memory lists.

Abstract: Edge terminations for polygonal impedance or resistance surfaces provide linearization of current flow to and/or from the surface through electrical connections at the vertices of the polygon. The edge terminations are constituted by a series of parallel ranks or rows of connective segments overlaid, inlaid or printed at each edge of the polygonal surface with the innermost row or rank being short straight segments and the length of each segment of the next innermost row, respectively, being longer. The central segment in each row or rank is electrically interconnected with the central segments in the other rows. A guard plane of conductive metal insulated from the impedance or resistance surface is also provided.

Abstract: An improved telephone circuit module incorporating a bridge lifter switching means which permits direct connection of party line subscriber circuits to a terminal block with the elimination of prior art saturable bridge lifters normally mounted upon a main distributing frame, and accompanying cable runs. The bridge lifter module comprises a solid state thick film circuit formed upon a ceramic substrate, suitably encapsulated, and is sufficiently small in overall size to fit within a connecting module which engages a part of a housing, and electrically conductive wire wrap terminals of certain types of known connector blocks.

Abstract: A time division electronic switching system including, as main structural elements, a central processing unit, a multi-frequency signal receiver unit, a signal processor and a time division switch including a speech path memory. Dial information from a subscriber or from another telephone office is detected in the multi-frequency signal receiver unit, the output of the multi-frequency signal receiver unit is written into the speech path memory, and an access circuit reads out the information written in the speech path memory and supplies it to the signal processor as read out information.

Abstract: A fail-safe magnetic sensing arrangement including a first and a second object relatively movable in relationship to each other. The first object includes a magnetic structure having a permanent magnet and a pair of pole pieces to develop a magnetic field. The second object includes an a.c. oscillator which is coupled to an amplifier by a saturable reactor transformer and the amplifier feeds a negative d.c. maker which normally energizes a relay except when the saturable reactor transformer is saturated by the magnetic structure which signifies that the second object is in the vicinity of the first object.