Abstract: A ringing signal generator includes a low power signal generator for generating a relatively low power signal representing a ringing signal, a bipolar pulse generator for generating a series of bipolar pulses having widths representing the amplitude of the low power signal, wherein adjoining pulses have opposite polarities, and a high power ringing signal generator for producing a high power ringing signal in response to the series of bipolar pulses. An analog sine wave signal is superimposed upon a DC bias signal to produce the low power signal.

Abstract: In a chip carrier for microwave components with an electrically conductive support and with a dielectric substrate, the electrical leads should be able to be impedance-matched in a simple manner. Such a chip carrier should be easy to insert in a microwave circuit and should have a simple construction. A recess (3) in the dielectric substrate (1) is in shape and size to the microwave component(s) to be mounted. The dielectric substrate (1) rests on the electrically conductive support (2). At least one microwave semiconductor component (4) is inserted in the recess (3) of the dielectric substrate (1). The ground terminals (11) of the microwave semiconductor component (4) are connected with the support (2) inside the recess (3). In the connection surface between the dielectric substrate (1) and support (2), the substrate (1) protrudes beyond the support (2).

Abstract: A variable-frequency I-V measurement system for testing the IC device, such as a GaAs MESFET, has probes for measuring the bias voltage, drain voltage, drain current, and gate signal voltage, a gate signal source, and a computer controller for controlling the gate signal source to provide, in sequence, gate signals varied in waveform, voltage, and frequency, in order to measure the I-V characteristics of the device in response to variable frequency gate signals. Values for maximum drain current (Imax) and percentage drop in Imax at different frquencies are derived and used to predict the RF performance characteristics of the device and to select good wafers early in the fabrication process, as well as for non-destructive testing of frequency dispersion effects on the device.

Abstract: A circuit for the conversion of an unregulated input voltage (UE) into a regulated DC output voltage (UA) is specified, with which the input voltage (UE) can assume both a higher and a lower value than the desired output voltage (UA). In addition to a set/actual value comparator (SIV), a current simulation (SNB) is provided, which simulates the current (JL) in the storage choke (L2) during charging as capacitor voltage, a common driver circuit (TRS), designed as switched constant current source, for both semiconductor switches (V1, V2), an input voltage monitoring (ESU), which switches off the switched-mode regulator when there is too low an input voltage (UE) and an output monitoring circuit (ASU), which reduces the set value of the regulating circuit on crossing in the downward direction of a selectable threshold.

Abstract: An overload protection circuit for power supplies and telecommunications apparatus such as multifrequency ringing generators causes the output voltage to become zero when a current overload is detected. The voltage is kept at zero for a predetermined period of time. Then the output voltage is restored. If an overload is still detected, the output voltage is again brought to zero.

Abstract: A sandwich ink-jet print head constructed in planar technology is welded into a dual in-line plug-in package which has on its top side a receiving opening for the sandwich ink-jet head and on its underside a contacting and balancing opening which can be sealed so as to be tight with respect to ink, as well as an ink inlet orifice for supplying the printing fluid. After insertion of the sandwich ink-jet head into the dual in-line package, the sandwich ink-jet head is electrically balanced via the contacting and balancing opening, to be precise by means of a resistor array arranged on the sandwich ink-jet head. As a result of the arrangement in a dual in-line package, the ink-jet print head can be mounted so as to be exchangeable in a mounting on the printer carriage. The ink-jet print head is connected to the ink supply system of the printer via a resilient adaptor.

Abstract: Casting of votes takes place by the dialing of a subscriber number of a stated destination switching center. By omitting establishing a connection to the destination switching center in the source switching center only the appropriate connection requests are summed and, after a predetermined sum value has been reached or after a given length of time has passed since the beginning of the vote taking, the particular sum value is signaled to the destination switching center via the common signal channel.

Abstract: A series ringing signal generator is disclosed which comprises a source of a user control signal. A programmable ringing signal generator is provided for generating an analog sine wave signal having a selectable amplitude and frequency in response to a selection signal. Finally, sequencing means, coupled between the source of the user control signal and the programmable ringing signal generator, is provided for generating a sequence of selection signals in response to said user control signal.

Abstract: The present invention describes a robust register circuit for protecting critical control points in data transmission and telecommunications equipment against software included failures. A circuit is provided wherein duplicated data words are written into a pair of registers of any desired bit length. A digital comparator determines whether the two data words are the same, and initiates a data transfer into a third register for transmission to critical hardware control points only when two identical sequential data words are recognized. When no such recognition occurs, new data is not transferred to the third register, and the hardware control points remain controlled by the previous data in the third register.

Abstract: A frequency multiplier is disclosed for producing an output signal having a frequency greater than the frequency of an input signal by a factor (1+N/M). The frequency multiplier comprises an input terminal and an output terminal; and a plurality of frequency multiplying stages, coupled between the input and output terminals, each producing an output signal having a frequency greater than the frequency of its input signal by a factor having the general form (1+1/P).

Abstract: With the switching node at least one coupling element is associated which has a number n of input lines and n output lines optionally connectible to the input lines via a space switch with a buffer store being assigned to the input lines in which k data packets occurring sequentially on the particular input line are storable before being routed further to the output lines indicated by the address signals contained in the particular data packet. The buffer stores have each a plurality m.ltoreq.k output terminals via which simultaneously m data packets stored in the particular buffer store and to be routed further to m different output lines are suppliable to a space switch having m.times.n input terminals and n output terminals.

Abstract: A semiconductor component with a power MOSFET and control circuit for controlling the power MOSFET. Both the power MOSFET and the control circuit have separate semiconductor bodies. The semiconductor body of the control circuit is arranged on one of the main surfaces of the semiconductor body of the power MOSFET. The control circuit is electrically insulated from the MOSFET by an insulating layer and mechanically coupled to the MOSFET by means of a bonding layer. The MOSFET is fastened to a cooling body which serves as a heat sink for the semiconductor component. The terminals of the control circuit and the MOSFET are attached to housing connections with leads.

Abstract: A circuit and method which eliminates the voltage spike generated by inductive kick, and generates a signal which is active while a relay is being released and for a given period thereafter. This signal can be used to power down circuits supplying signals to relay contacts, thereby allowing the relay to release without current or voltage potentials at its contact, e.g. dry switching. The generated signal may also be used to disable sensors which might give false indications while the relay contacts are switching. In telephone line circuits, the generated signal can be used to disable the telephone hook switch detector or to power down the battery feed circuit feeding the subscriber line. The relay coil energy generates a signal which is active while the relay is being released. The invention uses a minimum number of components and the circuit is adjustable as to how long the generated signal remains active after the relay is released.

Abstract: An adaptive compensator circuit is provided which includes a first echo compensator, responsive to data signals from the transmitter, for providing a first compensation signal for compensating an echo signal component which is linearly related to the digital signals to be transmitted. A second echo compensator, responsive to both the first compensation signal and the corrected received signal provides a second compensation signal for compensating the nonlinear echo signal component. An adder, responsive to the first and second echo compensation signals, provides a summed compensation signal. The data signals from the receiver are corrected by means of the summed compensation signal. In another embodiment, the second echo compensator is responsive to both the corrected received signal and the current symbol being transmitted by the transmitter and the (N-1) preceding symbols.

Abstract: The sealing and cleaning apparatus for an ink head consists of an electromotively driven endless band, on which two wedge-shaped wiping lips are arranged. For cleaning and sealing, the nozzle head is brough a close distance in front of the endless band, a surface of the endless band not provided with wiping lips serving as spraying surface for the squirting-out of the ink head. A cleaning device of wiping edge or cleaning roller removes the ink on the endless band. For covering in breaks in recording, the endless band has, furthermore, a depression formed by bulges, which is brough into contact in front of the nozzle plate or covering. For sealing, a convexly formed flexible pad, which is arranged between the endless belt, is pressed by means of a pressure-applying device against the endless band and cosequently against the nozzle plate. Due to the convex form, no air entrapment can occur in the region of the nozzle plate.

Abstract: Coefficient signals are generated for a transverse filter which receives data signals assuming W different amplitude values as input signals, with N successive input signals being stored in a serial-in-parallel-out (SIPO) storage arrangement having N storage cells. According to the input signals stored in the storage cells of the SIPO storage arrangement, predetermined filter signal coefficients possible for the W possible amplitude values individually are added and W corresponding partial sum signals made available. The partial sum signals are each multiplied by a factor corresponding to the particular amplitude value and subsequently added to form a sum signal. At least some of the product signals are multiplied by an additional correction signal coefficient assigned to the particular amplitude value. The additional product signals resulting therefrom are included in the formation of the sum signal.

Abstract: A probe tip is employed to measure electromagnetic fields without the use of a metallic conducting wire or cable which would otherwise distort the field being measured. The probe tip includes a variety of different circuits, each of which contains a separate battery, a powered field measurement sensor and an amplifier. A light source, which is internal to the probe tip and coupled to the amplifier, operates to convert the measured field to an analog optical signal. The analog optical signal is transmitted via an optical fiber to a receiver/preamplifier circuit which converts the optical signal to an electrical signal at the fiber's far end. This receiver/preamplifier device can be coupled directly to an oscilloscope or other instrument which are employed and used for the display or recording the magnitude of the electromagnetic field as measured by the probe.

Abstract: A software error detection circuit is described which supplements the known concept of a simple watch dog timer. The same clock pulse used to clock and time out a watch dog timer implements the addressing of a program memory. A comparison is then made of output data with data on a data bus. A failed comparison then raises an alarm faster and more efficiently than a timer circuit alone. Furthermore, in a parallel data bus environment a predetermined data check of adjacent bus line data is recommended over an all data or a random data check.

Abstract: A circuit configuration for the routine testing of the clock supply of a large number of digital TDM telecommunication units operated with the same clock, wherein a clock supply with stand-by generator through a corresponding arrangement of several monitor circuits and arrangements of on/alter switches, the operatability of the monitor circuits themselves can be tested so that on routine testing independent of the switching position of a change-over switching device effective upon switching a generator from stand-by operation to active operation respectively the same generator always acts upon the partial distribution system.

Abstract: Telecommunications equipment used in outdoor environments are subjected to harsh electrical conditions. Circuits which utilize sequential components, such as microprocessors, can therefore become confused due to extraneous power surges which may occur in the harsh conditions existing around the equipment. Furthermore, maintenance of the equipment has become much more automated, often leaving the equipment unattended for extended periods of time. In accordance with the invention, a circuit which automatically and reliably recognizes the failure conditions in the microprocessor, and automatically forces the microprocessor to recover is described.