Abstract: A pulling assembly for connectorized optical fiber cables is formed of a flexible metal braided hose portion for conveying a pulling force to said cable and for providing a chamber in which the cable connectors may be housed during a cable pulling operation. A cylindrical housing is attached to one end of said braided metal hose and includes a concentrically-arranged central strength member gripping apparatus and a buffer tube alignment structure disposed about the central strength member gripping apparatus. A crimping sleeve is attached to an opposite end of said cylindrical housing fixing said concentric arrangement within the cylindrical housing and being crimpably engageable with an outer surface of an optical fiber cable.
Abstract: To extend the dynamic range of an optical receiver with a transimpedance amplifier (TIV), it is known to operate the photodiode (PD) as an AC source at high light levels by using a DC-limiting element in the DC circuit of the photodiode, and to convert, by means of an AC circuit, the alternating voltage into an alternating current serving as the input current for the transimpedance amplifier (TIV), which lies within the permissible range. According to the invention, the AC circuit (C.sub.s, R.sub.s) runs from the photodiode terminal (2) not connected to the transimpedance amplifier input to the output (U.sub.a) of the transimpedance amplifier, whereby an extension of the dynamic range is achieved. The current-limiting element is preferably a transistor circuit (R.sub.E, T) connected as a constant-current source.
Abstract: A locking handle assembly used in combination with printed wiring boards and the like has camming portions which cooperate with a rod on the housing for the boards to act as a lever thereby positively seating and unseating its associated board within the housing. The handle assembly is provided with locking serrations. The serrations are positioned along radial curves so the handle is allowed to undertravel or overtravel, thereby compensating for tolerance buildup which could prevent proper seating of printed wiring assembly. An electrostatic discharge clip of the handle assembly engages the rod on the housing to ground the same and thereby prevent static electricity from the operator from producing an adverse effect on the electronic components.
Abstract: An H4 byte generating algorithm is implemented by circuitry which includes counters for generating the H4 byte. The circuit is provisioned to indicate whether it is operating in a terminal multiplexer mode or an add-drop multiplexer mode. In the terminal multiplexer mode the counters are allowed to free run and continually produce successive H4 byte outputs. In the add-drop multiplexer mode selected counter outputs are compared with the received H4 byte and the number of mismatches is accumulated by a mismatch counter. When the mismatch counter reaches a predetermined number the value of the received H4 byte is loaded into the H4 byte counters and the mismatch counter is reset. Each time a proper match between H4 counter outputs and the received H4 byte is sensed, the mismatch counter is reset to 0. The presence of a red alarm will also result in the resetting of the mismatch counter and free running of the H4 byte counters.
Abstract: An instrument for measuring ionization radiation acting upon a person is mounted in a housing which can be carried in the pocket of a garment, the housing includes a forwardly projecting portion having a radiation detector mounted in the forwardmost portion thereof, so as to be exposed to a wide angle of ionizing radiation. A display unit is located in an upper wall of the housing facing in a direction which may be read by the person.
Abstract: A line unit interface circuit used on line units in a line shelf of a digital loop carrier provides all of the logic necessary to access two subscriber lines to a line unit interface bus connected to common equipment within the line shelf. Information received from the common equipment includes signaling data, configuration data and provisioning data, which is reconfigured and processed by the line unit interface circuit for controlling the subscriber line channels. Configuration data from the common equipment is decoded to assign time slots on the line unit interface bus to the various channels serviced by the line shelf and to further provide for a timing offset between the transmit and receive strobes provided to each subscriber line circuit. A flywheel circuit is used to prevent erroneous time slot assignment in the event of noise or interference on the line unit interface bus.
December 15, 1989
Date of Patent:
February 12, 1991
Gary B. Cole, Michael J. Gingell, Joseph E. Sutherland, Paul M. Matsumura
Abstract: A fiber optic switch is formed using cylindrical or biconic fibers optic connector components for axially aligning pairs of fibers to be switched. The ferrules of the connector are rotatably mounted within an alignment sleeve, such that a pair of fibers in a first ferrule may be rotated relative to a pair of fibers mounted in a second ferrule to effect a bypass switch operation. Various forms of switch actuators, including rotary and linear actuators, are disclosed, along with fail-safe arrangements.
Abstract: In pulse code modulation communications systems where network links, using A, AB and ABCD signaling systems having different sized bit patterns and signaling rates for signaling operations, are interfaced, apparatus is provided to control the mapping of signaling patterns at signaling rate conversion boundaries.
Abstract: A mounting device for mechanically retaining separable transfomer core portions together and attaching the transformer assembly to a printed circuit board utilizing a flat clip body and a vertically aligned spring unit to minimize the transformer assembly height and four mounting legs to allow easy installation and removal.
Abstract: Two concentric corrugated metal tubes have a space therebetween in which there is arranged a superinsulation layer. Between the inner tube and the superinsulation layer there is located a helical spacer to ensure an annular channel to facilitate the evacuation of the space between the corrugated tubes. The spacer is formed of interlaced strands to reduce heat conduction therethrough.
Abstract: A remote control transmitter contains on a circuit board (3), which is rigidly connected to the transmitter housing (1) of the remote control transmitter, a positional-deviation switch configuration (17), which in the event of an angular deviation of the circuit board (3) and thus of the remote control transmitter beyond a particular trigger angle (a.sub.o) from a particular given or instantaneously determined reference operating position generates an output signal designating the direction of the positional deviation. In a signal converter (5) of the remote control transmitter, this direction-dependent output signal is converted as a control command into a transmission signal, and emitted via a transmitter element (4) of the remote control transmitter to a remotely controlled electrical appliance.
Abstract: By providing two comparators, each of which have a reference voltage level source connected to one input, and separate voltage level producing/enhancing circuits connected to the contacts of a relay, so that each alternate switch configuration produces a different voltage level at the two comparators, a unique relay switch detection circuit is attained. Preferably, three separate voltage level producing/enhancing circuits are employed, with one circuit connected between the relay output and the two comparators, while the other two circuits are connected to the primary or the secondary relay contacts. Futhermore, the voltage level resulting from each particular switch configuration is pre-set relative to the reference voltage level source imputs to assure that the two comparators produce different combined outputs for each alternate switched condition.
Abstract: A tool is provided for the purpose of allowing access to optical fibers held within a buffer tube. The buffer tube is held in a closed channel formed by the engagement of a clamp against a main body. A blade is inserted from the main body into the buffer tube so as to define a chord across the cross section of the buffer tube. The tool is drawn along the buffer tube so as to remove a portion of its protective covering threby allowing access to the optical fibers held therein.
Abstract: The application describes how the control of entertainment electronics apparatus or combinations thereof can be simplified to the point that even an unpracticed user can make all necessary or desired adjustments as easily as possible. Even in a large combination, all functions can be controlled from a single control unit. The control unit has only a limited number of clearly arranged, distinct control elements.
Abstract: An optical fiber cable having a predetermined length includes a plurality of optical fibers, each fiber having first and second ends. The first ends of the fibers are located coincidental with a first end of the optical fiber cable. The optical fibers are provided with differing lengths so that the second ends of the optical fibers are disposed at different locations along the length of the optical fiber cable. Indicia are provided on the cable to indicate the locations of the second ends of the fibers.
Abstract: A low speed channel bypass apparatus is described for reprovisioning the time slot multiplexer associated with an add/drop multiplexer so as to insure that particular low speed channel(s) within a high speed channel are passed through the add/drop multiplexer via the time slot multiplexer when the operation of an associated network controller is determined to be faulty. The low speed channel bypass apparatus is particularly directed for use with a high speed channel conforming to the synchronous optical network communication standard (SONET). A watchdog timer is used to monitor the performance of the network controller. The watchdog timer when timed out not only prevents further operation of the network controller, but instructs an associated reprovisioning apparatus to instruct the time slot multiplexer to connect through selected channel(s) from the east high speed interface to the west high speed interface.
Abstract: In a telephone system, a composite detection circuit and method for use in mechanized loop testing to detect both AC ringing and DC coin control voltage at a test access unit. An equalization circuit distinguishes between the two voltages and selectively amplifies the DC components of the voltages, thus amplifying the positive DC coin control voltages out of the detection range of the negative AC ringing voltages and vice versa. Two distinct outputs indicate either a positive or negative voltage detected. Two identical circuits are used, one on the ring line and one on the tip line, to detect positive and negative ringing and coin control voltages.
Abstract: By providing control logic for initiating a predetermined test sequence depending upon the known state of a relay, a unique testing circuit is attained whereby the relay drivers connected to the opposed sides of the relay coil are fully evaluated without causing the relay to be activated. In the preferred embodiment, the relay comprises a latching-type relay and the relay drivers comprise separate high-power CMOS devices. In this configuration, the control logic separately activates each transistor of each of the high-power CMOS devices without causing the relay to be switched between its two alternate configurations. Furthermore, the control logic originally sets the latching-type relay into one of its two configurations and then shuts off the power until activated for initiating the test sequence. In addition, the control logic is employed to check each transistor during the test sequence and assure its operation.
Abstract: An optical fiber cable contains a central strength member surrounded by a plurality of fiber-carrying guides traversing the length of the cable along reversing helical paths. A plurality of strength members are provided in lieu of selected symmetrically spaced guides. The strength members provide axial and torsional stability due to their reversing helical path. Periodic bandmarks are provided on each fiber for identification. An excessive length of fiber is provided in each guide to minimize fiber stress.