Abstract: A method for producing a fixed value memory (Read only memory, ROM) in the form of a programmable, monolithically integrated circuit, in which the fixed information is introduced into a semiconductor memory as binary coded bit pattern in process stages integrated into or following the conventional production sequence for semiconductor circuits including the direct transfer of the occupation of the memory cells, as prepared by software, with the elimination of masks. An electron or ion beam, which is deflected by means of deflecting means under the control of a computer is used to produce a mask on the surface of the semiconductor memory to correspond to the coded bit pattern, and thereafter, by selective process steps, the memory cells of the memory circuit below are caused to receive the desired stored value.

Abstract: An integrated circuit arrangement comprises a semiconductor body carrying an integrated circuit which is embedded in an insulating material casing together with a plurality of flat strip lines for making electrical connection with the semiconductor body, and a layer of electrically conductive material in or on the casing in a plane substantially parallel to the flat strip lines only on the side of the semiconductor body in which the construction elements forming the integrated circuit are located.

Abstract: A circuit arrangement for digitally indicating the frequency to which an AM/FM radio receiver is tuned in which the oscillations of the AM and FM oscillators are amplified and converted to rectangular oscillations whose frequency is counted by means of electronic counters and then digitally displayed. The oscillations of the AM oscillator and the oscillations of the FM oscillator are amplified and converted to rectangular signals by means of a common broadband amplifier which has a sufficiently broad bandwidth so that the oscillator frequencies for the AM range as well as those for the FM range are both passed and amplified, and the coupling of the input of the broadband amplifier to the outputs of the tuning oscillators is so loose that the tuning oscillators are not noticeably detuned by changes in capacitance of the broadband amplifier. The common broadband amplifier includes two inverters which are each designed as an integrated circuit, and have a fast rise-time.

Abstract: A device for exchanging substances, in particular, an oxygenator or dialyzer, comprises a stack of semipermeable membranes each having a plurality of longitudinally oriented capillaries embedded therein which open at each end. A porous tissue mass is disposed between adjacent membranes and define transverse gas flow paths therethrough from one side of said stack to the opposite side. A non-porous member closes off the top and the bottom of the stack and each longitudinal end of the tissue mass between adjacent membranes. A connecting piece is arranged at each end of the stack to provide for a flow path, for example, for blood, into the capillaries of each membrane and a similar connecting piece is arranged at the opposite end for the off-flow of the blood. Connecting pieces are arranged at each side for the inflow of a gas, for example, oxygen, into the tissues and for the outflow of the gas on the opposite side of the stack.

Abstract: An apparatus for irradiating a flowing material with an electron beam includes an electron beam accelerating device having an electron beam emitter; an irradiation device having an inclined irradiation tray arranged underneath the electron beam emitter and determining a flowpath for the material to be irradiated; and a material feeding arrangement for introducing the material onto the inclined irradiation tray. The material feeding arrangement comprises a riser vessel having an upper portion, a bottom portion and an overflow edge situated at the upper portion and adjoining the irradiation tray upstream thereof as viewed in the direction of material flow and at least one diffuser communicating with the bottom portion of the riser vessel for introducing the material thereinto.

Abstract: A process for the production of a tungsten carbide catalyst by carburization of tungsten oxides, comprises, directing a mixture of carbon monoxide and carbon dioxide over tungsten oxide while heating it in a heated reactor at a heating rate and gas flow rate such that the reduction of the tungsten oxide occurs more slowly than the diffusion of the carbon into the tungsten and into tungsten carbide which is formed during the reaction with the diffusion being faster than the separation of carbon from the gaseous phase according to the rate of adjustment of the Boudouard equilibrium. The carbon monoxide is charged at a rate of 560 1tr/h and the carbon dioxide is charged at a rate of 40 1tr/h and, after a reactor containing the sample of tungstic acid is positioned in a closed reactor, the reactor is flushed with the gases for around ten minutes and then placed into a muffle furnace. The reactor is heated to a temperature of 670.degree. C.

Abstract: In a fire control system for a weapon installed on a vehicle and including a stabilized sighting mechanism and a stabilized weapon, a range finder coupled to the sighting mechanism, and a fire control computer for calculating the lead and elevation angles to a target, circuitry is provided to automatically compensate for the inherent movement of the vehicle in the computation of the lead angle.

Abstract: The isolating transformer has two windings galvanically separated from each other and each connected to a respective point, which points are set at various high voltage potentials. At least one additional transformer is provided in series with the isolating transformer, and has two galvanically separated windings, with one winding being galvanically separated from the isolating transformer and the second winding being galvanically connected to a first winding of the isolating transformer.

Abstract: During the successive discharge and conveyance, along a conveying path, of items of mail from a stack by a continuously driven conveying device and an externally controllable removal member arranged to transport successive items from the stack to the region of action of the conveying device, the desired spacing between each pair of successive items is established automatically as a function of the length of that item of such pair which is the leading item on the conveying path such that for a leading item whose length exceeds a predetermined length value, the next succeeding item is transported from the stack when the distance between the trailing edge of that leading item and the leading edge of the next succeeding item reaches a given first spacing value, and for a leading item whose length is less than the predetermined length value, the next succeeding item is transported from the stack when the distance between the leading edge of that leading item and the leading edge of the next succeeding item reaches

Abstract: A sorting conveyor for flat rectangular items has a guide surface extending in a conveying direction; a drive continuously moving along the guide surface in the conveying direction; a plurality of pusher fingers attached in a spaced relationship to the drive for individually engaging and serially conveying the items along the guide surface in the conveying direction; and at least one feeding station operatively coupled to the sorting conveyor for introducing items thereinto.

Abstract: In order to monitor the conduction cutoff phase angles of a plurality of controllable rectifiers arranged in two groups in a rectifier bridge, a signal proportional to the angle for each rectifier is stored in a respective sample and hold member after each occurrence of a positive blocking voltage at that rectifier, and the minimum of the currently stored signals is observed.

Abstract: A semiconductor arrangement for switching large currents comprises a drive transistor and an output transistor connected together in the manner of a Darlington circuit and being of the same region sequence, a further three region semiconductor component of opposite sequence being connected by its central region to the base of the drive transistor, by the outer region to the base of the output transistor and by its other outer region to an electrode of the output transistor which is not connected directly to the drive transistor.

Abstract: Electronic switch for use as a crosspoint in switching networks of space-division telephone exchanges where it is connected to function as an open circuit stable negative resistance provding ON-attenuation compensated signal transmission, the switch being constituted by a circuit arrangement which lends itself to monolithic integration and which, when switched off, prevents undersirable attenuation of crosspoints connected to the same row or column of the switching system.

Abstract: A contact structure for a multiple semiconductor component comprises at least two adjacent hand shaped connecting contact arrangements with the fingers parting in opposite directions and splayed out, each finger being interrupted by one of the individual semiconductor components.

Abstract: A fine tuning circuit for a superheterodyne receiver including an oscillator whose output frequency is automatically regulated to the value of the rated frequency when the frequency of the oscillator deviates from the rated tuning frequency assigned the receiving channel by means of a control arrangement including a counter for periodically producing a count representative of the oscillator output frequency in a manner such that successive counting states of the counter correspond to oscillator frequency differences which are smaller than the frequency differences between adjacent rated tuning frequency values and with selected counting states being associated with the rated tuning frequency values, and a signal generating arrangement for deriving the control voltage from the counting state of the counter.

Abstract: An oscillator for producing rectangular pulses comprises a Schmitt trigger controlled by an R.C. element connected in series, a constant current source for charging up the capacitor and a current image circuit for ensuring that the discharge current of the capacitor is consistent with its charging current.

Abstract: A method of determining the fundamental frequency or pitch period of a voice signal from a difference signal, formed with the aid of predictors, between the original voice signal and the voice signal estimated by the predictor. Only the significant characteristics of the difference signal are then auto-correlated and the maxima of the correlation coefficients determine the fundamental frequency or pitch period.

Abstract: A pulse generator comprises a comparator to the inputs of which are connected a capacitor chargeable by a power source and a voltage divider respectively, two transistors being connected to the output of the comparator, one to set the voltage ratio of the voltage divider and one to provide a discharge path for the capacitor and two additional transistors being selectively connected to the comparator output, one providing a different voltage ratio of the voltage divider and the other providing an independent discharge path for the capacitor.

Abstract: A microwave input circuit including a parametric upper sideband down converter for receiving an input signal whose frequency is not much different from the intermediate frequency produced at the output of the down converter. The down converter may be either of the series type or of the parallel type and has its signal input directly connected to a microwave antenna and terminated by the real antenna resistance (R.sub.g) or the real antenna conductance (G.sub.g), respectively, at the input signal frequency (f.sub.s1). The parametric down converter comprises a cascade connection of a parametric down converter stage and a parametric up converter stage with both of said stages being of the series type or of the parallel type. The down converter stage is terminated at its image frequency (f.sub.sp) with a real resistance (R.sub.sp) or a real conductance (G.sub.sp), respectively, and satisfies the following relationship for a series type down converter: ##EQU1## WHERE R.sub.

Abstract: In the control of power supplied to a load from an a.c. power source by varying the phase angle of the a.c. power alternation at which conduction is initiated, conduction triggering pulses are generated by the use of a single capacitor which is first charged at a selected rate starting from a time corresponding to a predetermined phase angle of the a.c. power alternation, until the voltage thereacross reaches a first value, whereupon a triggering pulse is initiated, and the capacitor is then charged at a selected rate until the voltage thereacross reaches a second value, whereupon the triggering pulse is terminated.