Abstract: The fabrication of a printed circuit board (26) usually includes the step of testing the board with a testing machine (24) to verify operability. The testing machine accomplishes such testing by transmitting test signals to the board via a transmission line (36) and then analyzing each response signals returned from the board in response to the test signals. To reduce the incidence of error, the testing machine (24) is compensated for the propagation delay of the line (12) which is measured by launching a first string of pulses into one end of the line whose opposite end is left open. A second string of pulses is sinultaneously launched into a programmable delay line (16) which delays each second pulse by an adjustable interval. After the generation of each first and second pulse, a check is made whether the first pulse has been reflected back to the first end of the transmission line at the same time the second pulse reaches the output of the delay line.

Abstract: A circuit package comprises at least one IC chip bonded directly in a hole provided in a wafer such that the surface of the chip and the surface of the wafer are in the same plane thereby accommodating TAB bonding of the chip to bonding pads provided on the wafer. The structure can include multilayer circuitry on the wafer.

Abstract: The process of interpolating between two different sampling rates at any point in a sampling interval is obtained using a transversal filter arranged as a continuously variable digital delay line in which the tap coefficients of the delay line are made to be a function of the coefficients of an nth degree polynomial and the delay between the two sampling rates.

Abstract: An actuator including a device made of thin film shape memory material mounted to a substrate. The thin film device is deformed from its original shape. Thereafter, the device is heated to restore the device to its original shape. Motion of the device occurs in the deforming and restoring steps, which is used to produce some form of work result.

Abstract: A switching mode converter with current mode regulation includes a passive network operative to waveshape a ramp signal in order to attenuate the leading edge spike of the sensed switch current. A passive pulse generating network generates a pulse in response to the generated ramp with the proper timing and polarity such that when superimposed on the sensed current waveform effectively cancels the leading edge spike of that waveform.

Abstract: A communication channel ownership arrangement where two call units (switching modules) each own certain ones of the bidirectional channels between the units. By virtue of ownership, a call unit can immediately assign owned channels to calls without consulting the other call unit. While the ownership of channels to calls may be artibrary at system initialization, ownership is modifiable on a per-call basis to dynamically adapt to the actual directional traffic patterns that are present at a given time to minimize the coordination and communication required between the call units.

Abstract: A switching power amplifier circuit has the functions of a power inverter and a switching amplifier embodied into one integral circuit. Two high frequency switching inverter circuits are connected back to back sharing the same inverter power transformer. One switching inverter circuit processes power from an input rail to an output capacitor while the other switching inverter circuit processes power from the output capacitor to the input rail. The output capacitor voltage is regulated with respect to a signal input in order to obtain the desired output signal waveform. A blocking capacitor in the output absorbs the DC component of the output capacitor voltage and allows a pure AC ringing signal to be applied to the load. In an application as a ringing generator circuit the signal input is supplied by a ringing signal oscillator circuit.

Abstract: A differential pulse code arrangement reduces the bit rate of a composite color video signal by sampling the video signal at a predetermined rate of m times the color sub-carrier frequency, predicting the present video signal sample from reconstructed past samples and forming signal representative of the prediction error in a first predictive loop. The bit rate is further reduced in a second predictive loop embedded in the first predictive loop by generating a signal predictive of the error signal and forming a signal corresponding to the difference between the error signal and the signal predictive thereof. The difference signal is quantized and encoded for transmission. The error signal is reconstructed by summing the quantized difference signal and the predicted error signal and the prediction of the error signal is formed responsive to the sequence of past reconstructed error signals.

Abstract: A system for selecting multiple interexchange carriers serving telephone switches interconnecting user telephone lines. Apparatus and a method interactive with telephone users creates data base records of user selected interchange carrier resources and encodes the user created data base records into telephone switch messages. The telephone switch messages are transmitted to telephone switches to enable the telephone switches to selectively interconnect user telephone lines with ones of the interchange carrier resources in accordance with user created data base records.

Abstract: The present invention relates to a method for providing noise fill in a communication system. The method comprises the detecting (16) of active and inactive information signal transmission periods to a destined end user, and the measuring (17) of background noise normally found in the transmission of the information signals to the destined end user. A noise fill signal is generated (21,22) and transmitted to the destined end user during information signal transmission gaps to that end user, which noise fill signal is at level below that of the measured background noise. Such attenuated noise fill level was found to provide improved subjective performance in, for example, speech transmissions when the noise fill is between -dB and -6 dB of the measured background noise level, with best subjective performance noted between the -3 and -6dB noise match levels.

Abstract: In a hermaphroditic connector (20), an optical fiber cable (24) extends through a cap (46) into a tapered passageway of a flanged bushing. Optical fibers extend through a bore in a wedge (65) having a truncated conical shape and being received in the bushing. Portions of non-metallic filamentary strength member (28) of the cable are captured between surfaces of a wall of the tapered passageway and the wedge which are substantially smooth to avoid damage to the strength members. Forces applied to the cable cause the wedge to be seated further in the bushing. The included angle between diametrically opposite lines on the wedge surface that lie in a plane passing through the longitudinal axis of the wedge enhances the locking features. The fibers also extend through a retention nut (70) which is turned threadably over a portion of the bushing and each fiber is connected to a plug (94) mounted adjacent to an end of the connector with one plug being received in an alignment sleeve (130).

Abstract: A technique for avoiding accidental actuation of communications system devices which respond to a predetermined pattern of signals. In accordance with the present invention, data to be transmitted through the communications system is scrambled so as to reduce the likelihood of the customer data mimicking the predetermined pattern of signals. At the receiving end, the scrambled customer data is descrambled to its original condition.

Abstract: An opto-electronic organizer on a printed wiring card includes a plurality of opto-electronic devices each having electrical leads and at least one optical fiber extending therefrom and an optical fiber channel in the form of a closed loop for directing optical fibers. The opto-electronic devices are attached to the optical fiber closed loop channel at predetermined locations therealong and the optical fibers extending from the devices are directed into the closed loop channel wherein they are selectively interconnected. The closed loop channel has first and second portions and at least one channel joining the first and second portions so that optical fiber passing therethrough can reenter the closed loop either clockwise or counterclockwise. The organizer is affixed to the printed circuit card in predetermined alignment whereby the electrical leads extending from the opto-electronic devices are connected to prescribed electrical elements on the printed circuit card.

Abstract: The cordless static electric discharge unit for discharging static electricity from a human body into the air. The apparatus consists of a discharge unit attached to the wearer's wrist by a wrist strap. The discharge unit utilizes a radioactive source to ionize air and the flow of the ions discharges the human body. If the human body is at a positive potential with respect to ground, the negative ions flow to the human body whereas the positive ions flow from the discharge unit to a grounding point. The discharge unit is mechanically constructed such that sub-atomic particles emitted by the radioactive material are prevented from entering the human body or flowing into the surrounding air.

Abstract: This invention is a new type of Fabry-Perot cavity, and an optical communication system using such a cavity. The inventive Fabry-Perot cavity comprises both a waveguiding portion and a nonwaveguiding portion. In this manner, tunable cavities of desirable mid-range length, necessary to obtain required free spectral ranges, may be fabricated with minimal diffraction losses otherwise associated with cavities of such length. The cavity length may be varied using, for example, piezoelectric elements, and the various cavity elements may be aligned and connected, using fiber connector technology.

Abstract: Apparatus for mounting component magazines on a component insertion machine ncludes a pair of pins extending from one surface of each of the magazines and a pair of corresponding openings in a plate mounted on the machine, the openings being adapted to accommodate the pins. A lever slidably mounted on the plate has openings adapted to engage recessed cylindrical surfaces forming the bottom of annular grooves in the pins thereby locking the magazine in place.

Abstract: Ionic drift in integrated optical devices is reduced by the utilization of a gettering layer interposed between the surface dielectric and the electrodes. The material used to form this layer is capable of gettering the mobile ions at a relatively low temperature (for example <600.degree. C.).

Abstract: A stream of binary bits is converted into blocks of eight parallel bits. A first group of five of the eight bits addresses a memory device which has thirty-two code words each having four numbers representing the coordinates of signal points in four-dimensional space. The remaining three of the eight bits are expanded to four bits by a convolutional encoder having three bits of memory. These four bits are then used to multiply the four numbers of a code word read out from the memory device. This method permits a block of eight binary bits to be coded into any one of five hundred and twelve four-dimensional code words.