Abstract: An improved process for fabricating photonic circuits is disclosed. The inventive process starts with a growth of a base wafer comprising a stack of epitaxial layers of various materials. At least a portion of each of the material layers will ultimately be a functioning part of any of a number of devices which will form the PIC or will serve a role in at least one of the fabrication processing steps. Specific inventive processing steps are addressed to (1) interconnecting passive waveguides, active devices, and grating filtering regions without the substantial optical discontinuities which appear in the prior art, and (2) etching continuous waveguide mesas to different depths in different regions of the PIC so as to optimize the performance of each PIC device.

Abstract: Apparatus and method are disclosed for controlling the tone spacing (2.omega..sub.d) and output power level in an FSK lightwave transmitter. An arrangement is utilized which splits a tapped-off portion of the output data stream into two essentially equal components. A first component is then delayed and scrambled (polarization state) with respect to the second component. Self-heterodyning of the two signals results in forming a signal at the beat frequency, or tone spacing value. By comparing this beat frequency with a predetermined tone spacing value, adjustments may be made to the transmitter to maintain the desired tone spacing value. The self-heterodyned signal will also contain a component indicative of the data signal power level and may be utilized to adjust the transmitting device so as to maintain a constant power.

Abstract: A diversity receiving system for a differential phase shift keyed digital signal having symbols occurring in successive time periods comprises at least one antenna and a plurality of receiving branches. Each receive branch operates on a different version of the digital signal and detects different type prescribed components of the phase difference between successive symbols of the branch version. A detected prescribed component of the phase difference of each type is formed for each successive time period by processing the same type detected prescribed phase difference component signals from the receive branches.

Abstract: Disclosed is a connector module for making electrical contact between two essentially parallel boards which include contact pads on the edges. The connector includes at least one conductive member adapted to extend from a pad on one board to a corresponding pad on the other board. The connector also includes an insulating support member formed to extend from the top of one board, around the edge of that board, and to the top of the other board. This support member fixes the distance between the boards, permits the conductive members to make electrical contact for test purposes prior to clamping, and provides an appropriate clamping force for the connection to the first board.

Abstract: A telephone cord employs as an insulator for the conductors therein an extrudable blend of a styrene-ethylenebutylene-styrene copolymer with polypropylene.

Abstract: A novel low sintering temperature ceramic composition particularly suitable for multilayer ceramic capacitors is disclosed. The composition comprises a mixture represented by the formula(1-x)Bi.sub.2 (ZnNb.sub.2(1+d))yO.sub.3+6y+5dy (x)Bi.sub.3 (Ni.sub.2 Nb)O.sub.9where 0<x<1, 0.6.ltoreq.y.ltoreq.1.1 and -0.05.ltoreq.d.ltoreq.0.05.

Abstract: A ceramic capacitor with high Q factor and small temperature coefficients is made using a sintered dielectric comprising(1-y)Pb(Zn.sub.x Nb.sub.1-x)O.sub.3.5-1.5x.yPbTiO.sub.3wherein x is from 0.3 to 0.4 and y is from 0 to less than 0.1.

Abstract: A method and apparatus for rapid initialization of the transversal filter efficients in an echo canceler or echo measurement device is described. During initialization, a first data sequence is applied to a transmission channel, and an error signal representing the difference between the resulting echo and a replica thereof generated by the transversal filter is formed. The coefficients used to form the replica (in the case of an echo canceler) or to model the transmission channel (in the case of an echo measurement device) are then updated as a function of the error and a second data sequence which is orthogonal to the first sequence.

Abstract: A laser surgical instrument uses a CO.sub.2 laser source and an articulated arm structure to maintain single mode transmission of a 10.6 .mu.m beam to probe. In one configuration, high power is maintained for photo-transection and/or photocauterization. A second probe embodiment introduces other degrees of functionality such as aspiration, irrigation and internal viewing. Internal illumination is achieved by using the sheaths of quartz waveguides to transmit visible light while the laser beam is propagated internally in the waveguide structure.

Abstract: There is disclosed a circuit pack carrier molded as a single structure having an ample draft angle between the circuit pack guides to facilitate removal of the circuit pack carrier from the mold. The guides are cantilevered from the front and arranged into groups and a backplane board connected to molded alignment pins brings the circuit pack guides into parallel alignment. A slight inward flexure of the circuit pack guides is created for firmly gripping and holding in place inserted circuit packs. The unitary constructed carrier has special molded-in side wall channels for easily mounting the carrier to a frame or cabinet.

Abstract: There is disclosed a microcomputer having access sequence timing tailored to the requirements of a particular user. The device is arranged with a register for holding a parameter corresponding to a desired access cycle of the microcomputer. The register is adapted to receive from a user, either during manufacture, or during the execution of instructions, any desired parameter. Once the parameter is loaded into the register it will serve to control the cycle time of the microcomputer until such time as the parameter is changed by the user. Provision is made for changing the parameter on an instruction-by-instruction basis so that every instruction may have an independent execution time.

Abstract: In the disclosed coded telephone ringing signal method and circuitry, audibly distinguishable ringing codes are generated by alternately shifting between at least a pair of single frequency tones at different modulation rates. Other distinguishable ringing codes are generated by changing both the modulation rates and tone frequencies utilized.

Abstract: A circuit board connector (14) is assembled to a printed wiring board (11) by first aligning a plurality of leads (18) by urging them into spaced guide grooves (49) of a workholder (41). The spacing of the guide grooves (49) corresponds to the spacing of terminals, also referred to as solder lands (19) on the printed wiring board (11). Within the guide grooves (49) the leads (18) are retained against a possible, lateral resilient stress while a deformable material, such as a solder, is formed across the leads and into spaces between the leads (18). The solder temporarily retains the spacing between the leads while the leads are removed from the workholder and become aligned with the lands (19). During the assembly of the connector (14) to the printed wiring board (11), the leads become resiliently deflected perpendicularly to the plane of the printed wiring board (11). The deflection generates a resilient force which frictionally urges the leads and the lands into contact with each other.

Abstract: An electronic device assembly (11) includes a heat dissipating substrate (18) having a seat (16). A device (14) is uniformly spaced from a base surface of the seat (16), and a layer of solder of uniform thickness occupies a gap between the surface of the seat and the device. Leads (31) and (33) extend at a shallow, acute angle from the device. A lead (32) is mounted to a support (28) extending from the substrate (18). Inner portions of the leads (31, 32, 33), the device (14) and portions of the substrate (18), are encased by an envelope (22), while outer portions (67) of the leads and a mounting tab (19) of the substrate extend from the envelope.

Abstract: A cable which is capable of being made in a large pair size and yet which has excellent mechanical properties that maintain its integrity notwithstanding extremes in temperature during installation and shipping as well as during the rigors of installation includes a sheath system having a corrugated steel outer shield that is adhesively bonded to a plastic jacket. The corrugated steel shield which is formed to have a longitudinal overlapped seam that is preferably unsealed encloses an aluminum inner shield that in turn encloses a multiconductor core. Advantageously, the sheath system includes a plastic jacketing material which is capable of resisting biaxial stresses which are aggravated in a bonded sheath system. This results in jacket integrity about the longitudinal seam of the outer shield notwithstanding a notched cross-section and an unsupported bridged portion of the plastic jacket adjacent to the seam.

Abstract: A communications path having at least two stations coupled thereto. During time intervals when no station on the path has a packet to transmit, start-of-cycle packets for timing and synchronizing the stations are routinely transmitted between respective ends of the path. When a station has a packet of information to transmit, the station monitors the path for detecting whether or not the path is busy. On the one hand, if the path is not busy, a predetermined delay is introduced before the station is permitted to transmit a packet. The delay is related to the electrical distance between the station, which has the packet to transmit, and a station, which priorly transmitted a packet including a start-of-cycle packet. Also, the delay begins when the priorly transmitted packet is received by the station.

Abstract: A coating material is applied to drawn lightguide fiber in a manner which substantially prevents the inclusion of bubbles and which causes the fiber to be disposed substantially concentrically within the coating layer. The lightguide fiber is advanced through a continuum of coating material, which extends from a free surface of a reservoir and through first and second dies that are arranged in tandem, at a velocity which causes air to be entrained in the coating material. A pressure gradient is established between portions of the first die adjacent to its exit orifice. The first die communicates with the reservoir and is spaced from the second die to provide a chamber which communicates with a pressurized supply of the coating material.

Abstract: An enclosed electrical device (42) includes an electrical circuit (50) having elements (48-68) which lie substantially in and along a plane (115). A member (70) is applied to a one side and a member (85) is applied to another side of the circuit (50) for at least partially enclosing the same. Conductors (48) and (49) of circuit (50) are fixedly penetrated, preferably by pins (74) which are fixedly engaged to enclosure members (70) and (85). Such engagement is advantageously provided by making the pins (74) an integral part of member (70), for example by including pins (74) in a premolded member (70). Such engagement is also advantageously provided by making pin-engaging sockets (94) an integral part of member (85), also for example by including the sockets (94) in a premolded member (85). By a preferred friction fit of pins (74) and sockets (94), the enclosure members (70) and (85 ) and circuit elements (48-68) are sufficiently fixed relative to one another to resist forces applied thereto in service.

Abstract: A line powered loudspeaking telephone is implemented entirely from electronic components, eliminating inductors and transformers. A three stage (521, 523, 525, 532) output amplifier is used with the loudspeaker impedance forming the output stage impedance. A feedback network (527, 528, 529, 530) is used between the amplifier input and output stages to provide the desired gain at audio frequencies while forcing the DC gain to unity. The circuit then functions to provide proper gain for audio frequency signals received from the communication line while reflecting onto the communication line the resistive component of the output stage impedance scaled by biasing circuit elements (518, 519) of the amplifier input stage, thereby maintaining the proper voltage-current characteristic of the communication line.

Abstract: A split-barrel connector terminal is presented wherein a wire connected to the terminal is released as a new wire is being connected. This feature is provided by aperture (13) located a predetermined distance from the wire receiving end of slot (12). When insertion tool (51) forces wire (61) into slot (12), wire (52) is pushed into aperture (13) terminating its mechanical and electrical connection to terminal (11). Terminal (11) has locking shoulders (17) and (18) which permit insertion of the terminal into insulation sheet (32) but prevent removal of the terminal. Sheet (32) and sheet (33) are molded pieces which fit together to provide insulating housing structures for terminal (11). Slot (43) in the housing secures the wires connected to terminals (11) and provides a strain relief function. This arrangement reduces the number of parts making an otherwise complex assembly easily and economically manufacturable.