Abstract: A method and apparatus for determining the angular position of a point in rotational motion which includes a disk coupled to rotate with the rotating part. The disk includes a plurality of alternating teeth and spaces located about its periphery. At least one of the teeth has been removed to form an absolute or reference mark. A transducer is located adjacent to the disk to produce an electrical signal representative of the passage of teeth and spaces past the transducer. The electrical signal is processed to produce one or more output signals representative of the instantaneous angular position of the rotating part. Accurate results are produced even when large variations in instantaneous speed of the rotating part occur.

Abstract: An electronic pushbutton tunable radio (10) having various audio controls is disclosed. A single pushbutton (22) is utilized to implement volume, fader and balance modes of operation during which up/down pushbuttons (20,21) control the overall and relative magnitude of audio signals produced by four speakers (24-27) while at the same time a single display (17) is utilized to display, respectively, either the channel to which the radio is tuned, the relative magnitude between right and left speaker audio signals, or the relative magnitude between front and back speaker audio signals. The radio has tuning pushbuttons (14) for direct recall of preset radio channels in a tuning mode operation.

Abstract: For use in combination with "crash type" non-synchronous gear boxes, a gear ratio indicator which not only calculates actual ratio of transmission input shaft speed to output shaft speed, but also compares this determined ratio to the various available gear ratios within the transmission. The actual or determined ratio of input to output speed is then displayed in terms of the available gear ratios so that the operator is provided information as to the precise moment for engaging the transmission and also information as to which gear to engage.

Abstract: An improved telephone system selector unit employing an electronic control arrangement is capable of directly replacing or being added on to existing electro-mechanical switching arrangements of the Strowger or other types which position themselves directly in response to subscriber dial pulses. The electronic circuitry establishes rapid outlet scanning via a matrix of twelve-pole relays, each of which permits selection of three four-wire lines or four three-wire lines, depending upon a pre-selected operating mode. A digit treatment circuit evaluates the counter digits, selects the appropriate outlet group, and precludes scanning of restricted lines or numbers not present in the numbering plan. During scanning each three or four-wire circuit of each relay is scanned in turn until an available circuit is found. The digit treatment arrangement permits additional outlet groups to be added without regard to the numbering sequence.

Abstract: A circuit arrangement for determining the connection condition of a plurality of subscriber lines in a telecommunication network, each of the subscriber lines having two wires extending between a subscriber station and a subscriber line interface circuit and being connected via respective resistors to the two poles of a DC voltage source. For a group of such subscriber lines the operating conditions are consecutively monitored by sampling the voltage occurring at two sampling points of both wires by a respective multiplexor and passing it to a comparator having inputs which are temporarily inter-connected by filter capacitors each separately associated with a respective subscriber line interface circuit. In addition, the comparator receives a reference voltage determining a threshold voltage. For ground key indication one of the sampling points is connected to one input of a further comparator which second input is supplied by a corresponding further reference voltage.

Abstract: An electrically controlled safety mechanism for a highway exit ramp for detecting vehicle movement in the wrong direction, including a series of electrically controlled detection devices provided within the roadway, a warning member and support housing for the mechanism located adjacent to the roadway, and some distance beyond the road bed located detection devices, the warning member of the housing being pivotally mounted with respect to its base and capable of disposition in a nonoperative vertical position, but pivotal into a horizontal position when the detection devices sense the presence of a vehicle traveling in the wrong direction, a motor, brake, and speed reducer associated with the housing, for operation of the warning member, and for initiating its pivotal movements, the circuitry of this device including time operative electrical relay and electrical controller relays connected together for providing timed operations to the said motor and related mechanisms, so that the warning member will be con

Abstract: A system for providing an aircraft pilot and/or autothrottle and go-around pitch axis control with information when a go-around should be initiated during an approach in response to either a hazardous flight status of the aircraft or to wind shear encounter by the aircraft. The present system utilizes a gain schedule control law based on the bug speed set by the pilot and on pilot go-around criteria to trigger a go-around signal for the pilot and/or the automatic control systems.

Abstract: A circuit for coded symbol conversion has first and second memories and a switching stage. Standard code characters from a keyboard are entered into the first memory and if the entered character is one which can be represented by a single binary word the switching stage enables transmission of the single word. If the entered character is one requiring more than one binary word for representation the input is transmitted to the second memory which generates an equivalent set of binary words to represent the symbol and further transmission is delayed until all such binary words are generated.

Abstract: Current detection circuit arrangement for an automatic telephone exchange for detecting currents in a system of two conductors having earth as the common return conductor. This circuit arrangement comprises a pair of measuring resistors R.sub.1, R'.sub.1 and a pair of voltage dividers R.sub.2, R.sub.5 and R.sub.3, R.sub.4 which are connected cross-wise and form a bridge. The loop current I.sub.d can be detected with this circuit arrangement. It is also desirable for the circuit arrangement to enable the detection of the longitudinal currents in the conductors. The present circuit arrangement comprises a pair of connecting points for a detector for the longitudinal currents, one point of which is connected to the tapping point of one and to the tapping point of the other voltage divider, respectively, by way of separate resistors, the other point being a point of reference potential.

Abstract: The input surface of the apparatus for detecting X and Y coordinates of the input points comprises a first parallel electrode group, a second flexible parallel electrode group opposing and intersecting the first parallel electrode group. A pressure conductive rubber sheet which becomes conductive when the pressure is applied to the input surface is interposed between the two electrode groups. First and second resistors are provided which are in electrical contact with terminal ends of the two electrode groups. Electric signals from the first and second resistors are used to detect X and Y coordinates of input points on the input surface.

Abstract: A telephone fault isolation device is installed between customer telephone equipment, such as a PBX or KSU, and telephone company trunk lines feeding into such equipment, and is used to determine whether possible trouble is in the telephone company trunk lines or in the customer equipment. The device includes a monitoring device, such as a telephone handset, and an array of switches each associated with a telephone trunk line. Each of the switches, in a normal condition, connects the trunk line to the equipment, and, in a test condition, connects the trunk line to the monitoring device. A telephone customer can switch over each of the switches in turn and determine whether he can obtain dial tone on that respective trunk line.

Abstract: A system for providing within the cockpit of an aircraft to the operator thereof a dynamic indication of climatic conditions at an airport. Such climatic conditions might include wind direction, wind speed, visibility, barometric pressure, temperature, and cloud height, among others. A transmitting station within the airport includes one or more climatic condition sensors such as a wind vane, an anemometer, a barometer, etc., an encoder for providing an encoded signal indicative of the sensed climatic conditions, and a radio transmitter for transmitting the encoded signal. A receiving station within the aircraft includes a radio receiver for receiving the transmitted encoded signal, a decoder for decoding the encoded signal to provide the dynamic climatic condition data, and a display for displaying that data.

Abstract: A telautograph system allows a user at one location to write on a special surface, such as a chalkboard, and have the image appear at remote screens. Presently, a user wishing to call attention to an entry already written on the board must make a new line or must circle the item to which the remote viewer's attention is to be drawn. This procedure unduly clutters the image and a system has been devised which provides for a cursor (a graphical hand) to appear on the remote screen when the user touches the input surface at a point. The cursor also appears when the user is writing on the surface so as to call attention to the newly formed images. When pressure on the writing surface is released the cursor remains on the remote screen for a finite period and then automatically disappears, leaving the image unencumbered. When information is being removed from the input surface a graphical eraser appears at the remote screen at the site of the removed information.

Abstract: A subscriber line interface circuit is described wherein current supplied to a telephone subscriber line from a shared voltage source such as a DC/DC converter is regulated thereby permitting a regulated line current to be supplied to a plurality of line circuits from a single shared voltage source. In accordance with the present invention, both the dc line feed and the ac transmission requirements of a subscriber line interface circuit for a telephone exchange are implemented in a single circuit incorporating ac and dc impedance synthesis techniques. A significant reduction in the heretofore required expensive and bulky discrete components of the subscriber line interface circuit is achieved.

Abstract: A transparent intelligent communication network characterized by the rythmic storage and forwarding of multi-user packets comprised of mini-packets of customer data, wherein interconnection bandwidth is dynamically expanded when normal currently received information is insufficient to occupy all available bandwidth, thereby reducing backlogs of stored information and increasing efficiency of use of channel capacity.

Abstract: A graphic position-determining system incorporating two Sell-type transducers that generate acoustic shockwaves and receive their reflections from a surface whose position is to be determined and from fixed calibration reflectors positioned at known distances from the transducers. The design of the transducer includes plastic microspheres between a metalized membrane and a back-electrode to improve the sensitivity, the back-electrode having non-parallel surfaces to reduce unwanted vibrations and permit rapid damping. Apparatus is illustrated for determining the position of a movable cursor and for the verification or transmission of handwriting.

Abstract: A transparent intelligent communication network having both terrestrial and satellite links between nodes and providing improved channel utilization by including a system of reservations through successive links for the incoming data.

Abstract: The modular switching network for time-division telephone exchanges, which may be applied to small-capacity time-division telephone exchanges, is constituted by the direct connection of pairs of subscriber and trunk line connecting units by PCM digital trunks, each connecting unit comprising a concentration-deconcentrator device for serving the subscribers associated with this connecting unit.

Abstract: A sheet of optical fibers, circular at one end thereof and unfurled at the other end to form a straight line, is used to transmit laser-emitted light through a rotating prism and onto a photosensitive surface for electrophotographic printing or copying.

Abstract: A control circuit for momentarily energizing an electromagnetic coil in a teleprinting device recorder has a pair of switching transistors respectively operated by control pulses having a lag between respective switching times and a control transistor biased by a single operating voltage source. When a first of the switching transistors is switched on a rapid current rise in the coil takes place for immediate and rapid activation of the coil plunger which is followed by a maintenance time during which the first switching transistor is either switched off or is in pulsed operation and also during which the energy stored in the electromagnetic coil serves as the maintenance current source, which is followed by switching on of the second control transistor. By the addition of a diode between the coil and the operating voltage source, a feedback circuit is formed so that after disconnection of the electromagnetic coil, the energy stored in the coil is fed back into the operating currents supply network.