Abstract: An ergonomic support for portions of the forearm, wrist, palm and hand of a user of data entry devices. The support raises shaped hand cradles to a position whereby the user's fingers and thumbs may access all keys, balls, rollers and switches of the data entry devices while being supported thereby reducing loading on the upper extremities of the operator. The hand cradles are mounted on a tower fixed to a foot pad which are fabricated to slide over the support surface in front of the devices. An optional glide board may be placed under the devices if the support surface inhibits easy sliding of the foot pads. The front edge of the keyboard may be raised to accommodate the toe of the foot pads. A mouse support may be placed under a mouse device to raise the mouse to a height compatible with the keyboard.

Abstract: A keyboard, forearm, wrist and hand support device for use in conjunction with the keyboard of a video display terminal work station. The support device is adapted to reduce occurrences of repetitive strain injury by reducing stress on the user's shoulders, arms, wrists and hands. The support device comprises an elongate guide track and a pair of support assemblies which are adapted to support a user's forearms, wrists and hands thereon. Each of the support assemblies comprises a carriage member slidably engaged to the guide track and a linkage member pivotally connected to the carriage member. Pivotally connected to the linkage member is a support member which is sized and configured to support the user's forearm and wrist and the palmar surface of the user's hand.

Abstract: This invention relates to a keyboard forearm, wrist and hand support device for use in conjunction with the keyboard of a video display terminal work station. The support device of the present invention is adapted to reduce occurrence of repetitive strain injury by reducing stress on the user's shoulders, arms, wrists and hands. The support device comprises a pair of support members which are interfaced to a frame member via a pair of carriage members. The carriage members are adapted to permit the support members to be movable laterally and longitudinally relative the frame so as to provide complete access to the work surface of a keyboard positioned upon the frame. The support device may further include a finger-activated cursor control interfaced directly to the frame or to a keyboard positioned thereon for selectively positioning a cursor upon a display screen comprising a video display terminal workstation.

Abstract: A low frequency pilot signal having predetermined positive and negative excursions is applied to an electrical modulation signal input (26) of a Mach-Zehnder electrooptic modulator (18) together with an electrical input signal. A bias voltage VB selected to bias the modulator (18) at a linear point (V.pi./2) is also applied to the signal input (26). The optical output signal of the modulator (18) is sensed, and the magnitudes of the positive and negative excursions of the output signal which correspond to the positive and negative excursions of the pilot signal are compared with each other. If the modulator (18) is linearly biased as desired, the excursions will have the same relative relationship as the excursions of the pilot signal. If the modulator (18) has drifted away from the linear bias point (V.pi./2), one excursion will have a larger magnitude relative to the other than in the pilot signal, indicating the direction of deviation.

Abstract: A DC-to-DC up-converter of the type wherein voltage is built up across a capacitor by alternately connecting a coil by means of a pulse width modulator-controlled switching transistor across a low DC voltage source and, in series with that source, across the capacitor. Operation is initiated by converting the switching circuit into a blocking oscillator, running the oscillator from the low DC voltage source, and using the up-converted voltage to power the rest of the up-converter, making it possible to run the entire up-converter circuit from a very low voltage source.

Abstract: A quartz crystal oscillator is controlled entirely by digital elements to phase lock with a reference square wavetrain by alternately switching the tuning circuit of the oscillator between first and second configurations. The ratio of the times during which the tuning circuit is in its respective configurations is a function of the relative phases of the oscillator output and the reference wavetrain and serves to determine the precise frequency of the oscillator so as to keep its output locked to the phase of the reference wavetrain.

Abstract: The combination of headset receivers (10) and storage system (50) therefor is used in an aircraft passenger entertainment system. Each receiver comprises a housing (12) including electronics for receiving infrared wireless transmission, which is converted into audible signals and supplied to a listener's ears through stems (14). Storage of the receivers is in a case (56, 58, 72) having grid plates (74, 76) and a slitted sanitizing pad (78), for receiving and storing the receivers, and for sanitizing their housings and stems.

Abstract: In the present invention, a novel magnetic circuit maximizes the electrical power generated upon manual actuation of a push-button switch while minimizing the required weight of the magnetic materials. In particular, the magnetic circuit of the power supply of the present invention includes the following magnetic materials: an unmagnetized core (comprising iron) around which a coil is wound, the coil being connected to supply power to the transmitter; a permanent magnet (comprising iron having a permanent magnetic moment) mounted on a vibrating reed, at least one pole of the permanent magnet facing at least one end of the core. Actuation of the push-button switch induces oscillatory motion of the reed and of the permanent magnet. An advantage of this novel magnetic circuit is that, in at least one embodiment, the oscillatory motion of the permanent magnet causes a complete flux reversal through the coil during each cycle of the mechanical oscillation of the reed, a significant advantage.

Abstract: The invention is an electronic wire length measuring apparatus for accurately measuring and indicating the height of a traveling block above a fixed reference point in oil well drilling applications where a traveling block is hooked to a cable and pulley arrangement and to a winch drum, said winch drum being used to vary the height of the traveling block. The wire length measuring apparatus produces an output visual indication of the height of the traveling block independent of variations in drum size, wire size, number of layers on the drum, and the weight load on the traveling block, which causes a lower actual traveling block position due to stretching in the wire.