Abstract: A receiver for receiving a reception signal defining a measured value is connected to a two-wire transmission line used for transmitting a digital command signal from a communicator, a digital measured value signal from a transmitter, and a response signal responding to the command signal. The receiver includes a timer for discriminating that a nonsignalling state of the two-wire transmission line has continued for a predetermined period, and a CPU for validating a specific period of a reception signal received after the discrimination operation of the timer.

Abstract: In a communication system having a communication channel for transmitting data between a base station and a plurality of mobile radio units, wherein each radio unit has a unique identification (ID) code and wherein transmissions from each radio unit to the base station include the unit's ID code, a method is described for identifying which units are within RF communication proximity of the base station. The method includes: transmitting a range message, including a low ID code parameter and a high ID code parameter, from the base station over the channel to elicit a response from at least one of the mobile radio units having an ID code between the low and high parameters; determining whether radio units transmitted a message in response to the range message; and storing, responsive to transmission by the units, in an ID list a signal representative of the respective ID code assigned to such transmitting units.

Abstract: A keyboard assembly is disclosed comprising a waterproof portion which includes a sheet of printed key tips mounted on a cover support member overlying an indicia sheet identifying the key tips, first and second switch-matrix electrical conductors separated by an insulator sheet mounted on printed circuit board, a plurality of light-emitting diodes mounted in the printed circuit board for selectively lighting one of the key tips when operated, a plurality of I.C. circuit elements secured to the lower surface of the printed circuit board and connected to the electrical conductors forming an electrical circuit associated with the operation of the keyboard and a key operated switching mechanism extending through the keyboard to sense light emitted from elements mounted in the lower surface of the printed circuit board for controlling the operating mode of the keyboard.

Abstract: Self contained radio transmitting modules are mounted on power conductors at various places along electrical transmission lines. The modules are capable of measuring current, voltage, frequency and power factor (or the Fourier components thereof), the temperature of the conductor and the temperature of the ambient air. Up to fifteen modules may transmit on a single channel to a single local receiver. Each module transmits at intervals which are an integral number. The intervals between transmissions of all modules do not have a common factor and the average interval is the desired transmission rate.

Abstract: A data terminal interface device for use with personal computers having small or limited display capacities. A plurality of specific node setting capabilities of the computer. Designated keys are associated with the display to enable the operator to easily step through one general format or another.

Abstract: A telemetering system wherein a transmitting device responsive to an input signal derived from a sensor representing a metered variable, such as temperature or flow rate, is adapted to generate a corresponding direct-current signal. This signal is conveyed over a two-wire line to a receiving station through a terminal resistor across which a voltage signal is developed corresponding to the incoming current signal. The receiving station includes a DC power supply whose output is fed over the same two-wire line to the transmitting device to provide operating power therefor. In order to enhance the power available to the transmitting device, the current signal generated by the transmitting device lies in a 0% to 100% signal range in which the ratio of direct-current I.sub.o at 0% signal to direct-current I.sub.100 at 100% signal is greater than 1/5 or 0.2.

Abstract: An optical translator device capable of providing information indicative of the amount and direction of relative movement between the device and a surface positioned relative thereto. The device comprises a light source for providing at least partially coherent radiation and the source radiation is directed toward an area of the surface area. The reflected coherent radiation or light at the surface area undergoes optical interference due to the texture of the surface thereby forming a speckle pattern consisting of light and dark features. A detector array at the device comprises a plurality of photodetector cells and positioned in the path to receive the reflected light and to detect the light and dark features as represented by the cells in the array detecting light features in the reflected light thereby representative of a sample of the speckle pattern. Means is provided to compare consecutively produced samples which are indicative of the translatory information.

Abstract: A turn signal cancelling apparatus for a vehicle having a handlebar and a blinker unit which is operable to be activated by a manual operation and is operable to be deactivated by a cancelling signal.

Abstract: An aircraft automatic fault reporting system having a plurality of ARINC 429 low-speed data buses between the aircraft maintenance control panel and the aircraft communications addressing and reporting system provides two-way communication therebetween. Detected faults through an eight-digit fault code are by means of a transient logic circuit under certain conditions of the aircraft communications and addressing systems provided to maintenance personnel thereby eliminating flight crew use of FRM's.

Abstract: This invention is an input device that enables the user to take symbol sequences such as whole words, phrases, sentences, paragraphs, or other multi-symbol sequences from a computer's memory and have these symbol sequences printed out or displayed by some other means such as a computer monitor. This invention uses a grid of points of switch closure, where each point is identified by an alphanumeric or other code; and where each point of switch closure can be individually activated by the user. Printed sheets of material are accurately positioned over this grid of switch closure points. Printed on these sheets of material are: 1, symbol sequences; and 2, response areas adjacent to each symbol sequence. Each response area lies over one of the switch closure points.

Abstract: A control panel having a display for displaying selected statements from a plurality of stored statements containing one or more separate elements of alterable information; four selectively operable push-button switches; and a computer for storing the stored messages and controlling the display. The switches include left and right scroll switches and up and down-increment switches. The computer controls a cursor on the display movable left and right between one or more pre-programmed positions in each displayed statement in response to operation of the scroll switches. Each of the pre-programmed positions corresponds to one of the segments of alterable information. The scroll switches cause the computer to scroll left or right for sequentially displaying the next left or right statement. Scrolling to the next stored statement is in response to the scroll switch indicating an attempt to move the cursor left or right beyond the leftmost or rightmost pre-programmed position for the displayed statement.

Abstract: A static monitoring system for use with an electronic manufacturing work area, typically a conventional work bench having an electrical conducting strap for connecting the operator's wrist to earth ground, and including a circuit for indicating when there is an earth ground connection and circuitry for indicating when an electrostatically charged object, such as another human, approaches the work station. An antenna is positioned at the work station spaced from the working surface and from the operator, with the antenna connected as an input to an amplifier circuit which measures the change in electrostatic field strength and hence the approach of a charged object, with an indicator providing a visual or audible alarm or both. An oscillator provides an ac signal to each input of a differential amplifier, with one input connected to circuit ground through a capacitor and the other input connected to a wrist strap or the like on the operator.

Abstract: A two wire transmitter controls loop current as a function of a sensed parameter such as pressure or temperature using analog sensing and signal processing circuitry. Corrections, such as for zero, span, and linearity are provided in the form of analog correction signals by a digital circuit which includes nonvolatile memory, a microcomputer, and a digital-to-analog (D/A) converter. The microprocessor controls the D/A converter as a function of stored digital correction values to produce the analog correction signals used by the analog signal processing circuitry to control the magnitude of the loop current flowing through the two wire transmitter.

Abstract: An electrical signalling apparatus including a transmitter and receiver connected to the same electrical power distribution network wherein a signal generated by the transmitter is used to control apparatus connected to the receiver. The system uses a pair of amplitude-modulated low frequency signals as the control signals that react with the receiver to control apparatus connected thereto. The transmitter has an oscillator modulated by twin tuning forks and provides a signal for a period of, for example 10 seconds, determined by a time-delay relay. The receiver has a demodulator followed by two filters connected to integrators. As soon as the integrated signals reach a predetermined value, a control signal is transmitted to the output. This apparatus provides a communication system which is virtually insensitive to interferences on the distribution network and operates perfectly with weak signals.

Abstract: A computer control includes a control member movably mounted for movement in two dimensions wherein orthogonally related gratings are moved to the corresponding directions to generate pairs of quadrature related signals. Circuitry produces binary signals defining four states for each cycle of quadrature signals to change a corresponding count indicating position of the control member. In another variation patterns each having a plurality of spots with a unique combination of gray levels are sensed by a rectangular array of photosensers to determine the position of the movable member.

Abstract: A video art electronic system for drawing and coloring on a conventional color television video monitor includes a first joystick for drawing and a second joystick for coloring. The operation is in real time and is simple enough for a child to operate.

Abstract: To make possible a technically uncomplicated and reliable absolute displacement determination--in particular for the position determination of robot drives--a cyclic position transmitter (L) and a revolution transmitter (U) rigidly coupled therewith are provided, the sum signal of which indicates the displacement. As revolution transmitter there is used a transmitter (U) which makes use of the Wiegend effect.

Abstract: A finger-touch coordinate input apparatus according to the present invention comprises printed circuit boards provided between a display screen and its front frame and having light-emitting and light-receiving element groups thereon, and LED filters provided outside the printed circuit boards at a predetermined distance therefrom, constituting side edges of the display screen, and having light-transmitting portions at part thereof, wherein spaces formed between the printed circuit boards and the LED filters are connected to an air supply source so that an air flow is generated in at least one space, thereby easily and properly eliminating degradation of the detection function due to dust or the like at photodetectors in which the light-emitting and light-receiving elements for coordinate position detection are arranged.

Abstract: A system for warning the pilot of a rotary wing aircraft such as a helicopter of a flight condition that, if left uncorrected, would result in the tail of the aircraft striking the ground monitors the altitude above ground, descent rate, pitch and pitch rate of the aircraft and provides a warning if the relationship between the aforementioned parameters is such that a tail strike is imminent.

Abstract: Existing auditory warning systems are in general too loud and it is often difficult to distinguish between a number of different warnings. Further under different conditions warnings may change character due to masking by varying noise. A warning system is disclosed which is based on a microprocessor and waveforms for each warning sound stored in a ROM. The waveforms are read out to DACs and used to drive a loudspeaker by way of programmable attenuators. Each waveform is devised to have at least four quasi-harmonically related frequency components at a power level in the range 15 to 30 dB above threshold. In this way the sounds are distinctive and do not change character with varying noise levels below threshold.