Abstract: When triggering a bipolar switching transistor the control current for switching on the bipolar switching transistor must be set properly. If the transistor is oversaturated, the switch-off time response is poor. With too low a control current, however, high forward losses occur. A method and circuit configuration for base current regulation of bipolar transistors in periodic switching operation is introduced. The method provides defining as a measure of the saturation of the switching transistor the base current time integral required for sweeping the base region of charge carriers, and setting as a function of this value the base current for switching on the switching transistor.

Abstract: A computer operated controller for controlling and/or monitoring a physical object and a logical abstraction related to the physical object is disclosed. The controller comprises a physical object entity representing the physical object. The physical object entity includes storage for physical-object-specific data and a script describing the behavior of the physical object. The controller further comprises a logical abstraction entity representing the logical abstraction. The logical abstraction entity further includes storage for logical-abstraction-specific data and a script describing the behavior of the logical abstraction.

Abstract: A process for making metallized holes in a dielectric substrate which, after galvanic growth of the conductive paths delimited by photoresist on the substrate, includes a drilling step of the substrate and electrogalvanic creation of rivets protruding beyond the edges of the holes on the front of the substrate. The steps of completion of the conductive and resistive paths on the front, deposition of metals on the back, reinforcement of the rivets and galvanic growth of the back and of the metals deposited inside the hole then follow.

Abstract: A comb-line band-pass filter with circular cross section is made up of internal rods constituting the resonators of the filter and brought to resonance by the use of tuning screws and alternating with coupling screws. In the filter the rods are inserted in such a manner that each one is rotated in relation to the preceding one by an angle of 0.degree.<.alpha.<90.degree. while the coupling screws are placed at an intermediate angle. For equal electrical characteristics the length of the filter is also a function of the rotation angle of the rods.

Abstract: Thyristors utilized as protective elements receive trigger current by way of a respective semiconductor switch having a control electrode thereof coupled to a supply battery. The supply battery thus need only supply the sum of control currents for respective semiconductor switches whereas the current required by the protective thyristors is provided by the interfering source, for example, by a stroke of lightning.

Abstract: A radar system operating by the line-of-sight method requires an accurate measurement of the relative position of at least two objects. By sending out coded radar transmission pulses, control data are transmitted to a guided flying body in a radar beam, which sends back an echo signal to the receiver via a transponder. In order to measure the passive signal and the transponder echo signal in the radar beam as accurately as possible, common reception channels are provided for both echo signals containing, inter alia, arrangements to equalize the dynamic levels of the echo signals. The returned transponder echo signal corresponds with respect to coding and bandwidth to the transmission pulses originally generated in the transmitter and that are phase-coded but not provided with the control code.

Abstract: A low offset transconductance amplifier, in an analog electronic cochlea comprises: first and second differentially connected input transistors; an input current source transistor; an output current sink transistor; first means for inducing a current in the output current source transistor in response to the first input transistor; and second means, for inducing a current in the output current sink transistor in response to the second input transistor, including a cascode transistor.

Abstract: A method of altering a refractive index, as for an optical waveguide, as in a buried heterostructure laser, by inducing disordering in a region of a semiconducotr body comprises exposing a surface portion of the semiconductor body to plasma etching, coating at least a part of the surface portion with an oxide layer, heat treating the semiconductor body.

Abstract: To an output terminal of a hybrid circuit with output signals mutually phase shifted 90 degrees is connected a half-wave line section while to the second output terminal is connected a low attenuation filtering network having a phase characteristic which is -90 degrees at the center frequency and varies with the frequency like a half-wave line section.

Abstract: The invention relates to a photo-laser transistor with a base-collector pn-junction biased in the non-conducting direction and a base-emitter pn-junction biased in the conducting direction. With the invention, the functions of optical to electronic conversion, amplification, electrical to optical conversion, and, in particular, that of an optical repeater are to be realized in one single semiconductor element. For this purpose, the invention provides that the base-emitter pn-junction is formed as laser diode, that the laser diode is driven with a base precurrent to approximately its threshold value, and the residual current, which needs to be made available for stepping over the threshold, stems from the amplified photocurrent of the base-emitter pn-junction.

Abstract: A method is disclosed for controlling the release of jobs from a pool of pending jobs into a factory, which includes a plurality of machines processing jobs-in-progress, which comprises the following steps. First, a continuity index (CI) is calculated for one of the jobs in the job pool, which is related to the total amount of processing time required by that job, and the antipicated time to finish that job. Second, a mean continuity index (MCI) is calculated related to the CI of all of the jobs processed by the factory in a predetermined period of time. Third, a lower range (r.sub.1) and an upper range (r.sub.2) are calculated which are releated to the utilization factor of the machines and the fraction of jobs which are on time. Finally, a job is released from job pool into said factory if:MCI-r.sub.1 .ltoreq.CI.ltoreq.MCI+r.sub.2otherwise, the steps are repeated for the other jobs remaining in the job pool.

Abstract: In a radar system, comprising a digital expander, two analog modulation signals are generated with two digital to analog converters and raised to an intermediate frequency range through a quadrature modulator. The amplitude and phase ripple of the output signal occurring in the quadrature modulator due to limited carrier and image frequency suppression are compensated through a multiple regulating circuit. To this end, if necessary calibration signals, of constant amplitude and different phase positions, are generated sequentially by means of the two digital to analog converters and the amplitude of their output signals measured in an amplitude detector. Setting values for the multiple regulating circuit are determined from the averaged amplitude measured values in a phase and amplitude correction unit which via setting elements set the requisite offset and phase and amplitude symmetry values until the deviations of the output signal in amplitude and phase disappear.

Abstract: An echo canceller circuit contains a network of capacitors binary-stepped in their capacitance, whose one set of plates, representing a center of the network, each are switchably connectable to a reference potential or, in the case of less significant bits of digital information to be converted, to ground potential, or to a fraction (U3, U4) of the reference potential. To avoid difficulties which might result from the offset voltage of an integrated operational amplifier (V) connected to the capacitor network, the network is composed of two symmetrical halves (COo' to C32o; COn' to 32n).

Abstract: A telephone subscriber circuit of a telephone exchange comprising active circuit elements with a capacitively-complex input impednace, wherein the signal which is to be transmitted from the exchange to the subscriber is amplified by two operational amplifiers operating in push-pull and is fed via two coupling arms, formed by a series arrangement of a capacitor and a resistor, into the subscriber loop which is itself supplied with d.c. current via two supply resistors. The subscriber circuit in accordance with the invention serves as a compensation network which directionally isolates the signals of the two speech directions and which includes two arms via which the symmetrical subscriber signal is supplied to a subscriber amplifier. In accordance with the invention the entire complex input impedance is sub-divided into a complex and a real component. The complex component serves as a coupling arm which supplies the LF-signal which is to be transmitted and which blocks the d.c.

Abstract: Line trunk groups coupled to a double central switching matrix by way of two PCM lines and including sub-switching matrix and group control units are allocated to one another in pairs. Prepared for stand-by service switch-over by the central switching matrix and the processor are subscriber and trunk lines within each line trunk group pair, which are connected to the sub-switching matrix of a first line trunk group and are switchable to that of a second line trunk group, such that their group control unit also assumes the control functions. The processor going into service with the stand-by switch-over is connected with the group control units of all first line trunk groups via its central switching matrix, while all switching service continues with those of all second line trunk groups. Connection data of all existing connections are stored in all group control units.

Abstract: A semiconductor component. The semiconductor component has two superimposed semiconductor layers of different conduction materials. An upper layer is provided with an opening through which a lower layer is exposed. A space saving scheme for connecting electrically the two layers is provided, by depositing a connecting layer which contacts the upper layer at an edge only and the lower layer is contacted at its depth where its doping material maximum is located. This requires a doping equal to or greater than 10.sup.19 cm.sup.-3 for the upper layer, which is dependent on thickness.

Abstract: A circuit arrangement for telecommunication switching systems, including PCM time division multiplex telephone switching systems, with double central switching matrix by which two corresponding line trunk groups comprising a sub-switching matrix each and a group control unit each, are allocated to each other in pairs via two time-division-multiplex lines. The line units and the PCM-lines leading to the central switching matrix, which are individually respectively allocated to the two line trunk groups, and which are connected with the respective sub-switching matrix of their own line trunk group during normal service, are switchable, during emergency service of one of the two line trunk groups, to the sub-switching matrix of the respective other line trunk group.

Abstract: A transformerless hybrid circuit arrangement for a subscriber line interface circuit of a telecommunications exchange is disclosed. A preferred embodiment of the hybrid arrangement comprises a first and a second operational amplifier plus a differential amplifier connected together in the following manner: The non-inverting input of the first operational amplifier is connected to a first reference voltage and the output of this amplifier is connected (1) via a first resistor to one wire of the two-wire subscriber line, and (2) via a third resistor to the inverting input of the amplifier. The non-inverting input of the second operational amplifier is connected to a second reference voltage and to the receiving branch of the four-wire line of the telecommunications exchange.

Abstract: A circuit arrangement includes a memory arrangement in which data signal bits forming the data signals can be read in at read-in times determined by a first clock pulse train and from which these data signal bits can be read out at read-out times determined by a second clock pulse train. A monitoring arrangement periodically and repetitively provides a test bit which can be read into or as the case may be out of the memory arrangements in parallel to the data signal bits. At its initialization, this monitoring arrangement enables the reading out of data signal bits previously entered in the memory arrangement with a delay, such that thereafter a predetermined phase relationship exists between test bits read into and read out of the memory arrangement. The monitoring arrangement provides a control signal which disables the memory arrangement lilmited in time with regard to the reading out of data signal bits and test bits when a defined predetermined change in this phase relationship is exceeded.

Abstract: A telephone station subscriber line interface circuit for connecting a telephone subscriber station to a telecommunications transmission line comprises a loop current sensing circuit for providing an output signal proportionately representative of DC resistance in the telecommunications transmission line. A ring-side driving circuit is coupled to the loop current sensing circuit and is responsive to the output signal for providing an alternating current voltage source and a direct current voltage source to a transmit amplifier in periods of high constant DC resistance in the telecommunications transmission line, the ring-side driving circuit maintaining the output of the alternating current voltage source constant to the transmit amplifier and automatically transferring from a constant direct current voltage source to a constant direct current current source in the event of a decrease in the DC resistance in the telecommunications transmission line sensed by the loop curent sensing circuit.