Abstract: A signal input circuit comprising a control member for the controllable attenuation of the input signal and firmly set reactances for the selection of the input signal, wherein the reactances are connected and dimensioned in such a way that there exists a circuit point which has a large impedance compared to the impedance of the signal source, and the control member acts upon this circuit point.

Abstract: Apparatus for recording an information signal on a metallic record carrier. The information is impressed on the carrier by cutting a groove therein by means of a stylus, the groove being characterized at each point by a slope or modulation pitch angle. The stylus has a longitudinal axis, a leading edge substantially parallel to this axis and a trailing edge. The angle between the longitudinal axis of the stylus and a normal to the surface of the record carrier is greater than 10.degree. and not more than a value which would make the angle between the trailing edge of the stylus and the surface of the record carrier less than the maximum modulation pitch angle. The stylus is movably attached to a fixed structure by a mounting member and is electromagnetically excited by a driving member to shape the grooves in the record carrier in accordance with the information signal.

Abstract: The invention relates to a circuit for a computerized photoflash control which is supplied, preferably with the aid of a photographic element, with a current corresponding to the reflected light during the flash, from which an electrical quantity terminating the flash is derived. The invention consists in that the circuit contains a comparator, with a voltage derived from the current supplied at one of its inputs, while the other input of the comparator is supplied with an adjustable reference voltage. Connected to the output of the comparator is a switching path which is actuated by the comparator upon signal output, thereby terminating the flash.

Abstract: An electronically controlled ignition system is provided in which the point in time at which the primary current flowing through the primary winding of the ignition coil starts, is controlled as a function of speed so that the said primary current only reaches the value required for ignition just before the ignition time and in which immediately before the ignition time, it is ascertained whether the primary current has reached the value required for ignition, wherein if there is no primary current or insufficient primary current to prevent ignition during periodic fluctuations in speed, the electronic control arrangement is switched off for a fixed period and the time at which the primary current is used is derived directly from the control signal of the ignition pulse generator and in which, once the switch off period has come to an end, continuous and automatic electronic control is reinstituted.

Abstract: An ignition system has an electronic control unit which produces trigger pulses in response to received ignition control signals, the control unit also receiving test pulses indicating the period of time for which current supplied to the primary winding of the ignition coil is at its maximum value, the control unit extending the test pulses and supplying the extended pulses to a logic circuit which, when a trigger pulse occurs without an extended pulse simultaneously occurring, produces an output signal to indicate misfiring, and to temporarily switch off the control.

Abstract: A thermoelectric level measuring device for measuring the fill level of a container having a filling material therein and a free space above the filling material comprises a series connection of three sensing resistors, the first of which is always surrounded by the filling material, the second of which is intended to be surrounded by the filling material and by the free space and the third of which is always located in the free space and an evaluation circuit connected to each end of the series connection and to the connection points between the sensing resistors.

Abstract: In a circuit arrangement including at least one control loop composed of a controllable oscillator for producing an a.c. output signal whose frequency is a function of the value of a control signal thereto, a frequency/d.c. signal converter connected for producing a d.c. output signal which is a function of the frequency of the oscillator output signal, and a signal comparator having two inputs and an output, with one comparator input receiving a signal corresponding in value to the converter output signal, and the oscillator receiving a control signal corresponding to the signal at the comparator output, the circuit arrangement further including an a.c. signal source, and a second frequency/d.c. signal converter connected for producing a d.c. output signal which is a function of the frequency of the a.c. signal produced by the source, with the other comparator input receiving a signal corresponding in value to the second converter output signal.

Abstract: A variable capacitance diode comprises a low resistance semi-conductor substrate on which is epitaxially deposited three layers, a first layer adjacent the substrate having an impurity concentration which decreases towards the substrate, a very thin intermediate region and a relatively thin surface region of lower doping than the intermediate region, a barrier being formed on or in the outer surface of the relativey thin surface region.The invention also includes a method of making such a diode.

Abstract: A zero voltage switch comprises two parallel connected current branches for taking over the D.C. current from a D.C. current source in half cycles of an A.C. voltage and a third current branch for blocking the other two current branches in zero axis crossing phases of the A.C. voltage so as to produce control pulses, a logic unit being provided for controlling the D.C. current source whereby an extremely small current is provided up to the beginning of a first control pulse, an increased current is provided during the control pulses and an intermediate current is provided between the control pulses.

Abstract: A clock signal generator comprises a counter, a shift register and a logic circuit, the generator receiving a clock input signal of constant period and producing a clock output signal of which the period increases according to a geometrical ratio, within each shift cycle of the shift register.

Abstract: An input stage for an ignition control circuit is provided for producing an output signal from a comparator which switches the primary current circuit of the ignition coil in dependence on a control signal in which the control signal causes alternate switching of two current multipliers, a first charging current determined by a charging resistance and a second charging current determined by the first current multiplier charges a first capacitor, a third charging current derived from the second charging current charges a second capacitor, a first discharge current determined by a discharging resistance and a second discharge current determined by the second current multiplier discharges the first capacitor, a third discharging current derived from the second charging current discharges the second capacitor and a comparator compares the voltage at the second capacitor with a reference voltage to produce an output signal for switching the primary current of the ignition coil.

Abstract: A feedback amplifier which is constructed as a threshold value switch includes a current fed differential stage and additionally comprises two transistors whose emitters are each connected to one output of the differential stage with a first resistor connected between these two outputs and second and third resistors forming operating resistors connected between the supply voltage and the two transistors, each operating resistor being connected to the collector of one transistor and the base of the other transistor respectively.

Abstract: In an orientation arrangement during journeys in vehicles on land, means are provided for the purpose of ascertaining the distance covered by the vehicle and the changes in the direction of the vehicle. The distance covered by the vehicle and its respective location are ascertained and indicated with the aid of the distance measured and the changes in direction which have been ascertained.

Abstract: A method for digitally regulating the residual carrier phase error in receivers of digital data transmission systems. A comparator compares the sampled data signal or value of the carrier demodulated input signal to the receiver with the estimated value for each associated sampling time or moment as provided by a decider, to determine the deviation dk which is a measure for the phase difference between the sampled value and the associated estimated value. This deviation dk is filtered in a digital loop filter, including a proportional branch and an integration branch, and a regulating value for the demodulated input signal is obtained from a subsequently connected accumulator. A non-linear limitation on the deviation dk is included in the integration branch of the digital loop filter.

Abstract: A power connector for providing overload protection for an electrical operating station connected to a power mains, composed of at least one overvoltage arrester of a first type which is capable of quenching the power mains surge current and at least one overvoltage arrester of a second type connected in series with said arrester of the first type, with the insulation of one overvoltage arrester, in its unfired state, meeting the requirements of a basic insulation or of the supplementary insulation for a protective insulation, and both arresters being constructed for dissipating the pulses generated by a direct stroke of lightning or nuclear electromagnetic pulses without adversely affecting the protection afforded thereby.

Abstract: In an overvoltage arrester composed of two electrodes each presenting a side wall and an end wall transverse to the side wall and whose perimeter is bordered by the side wall, the electrodes being spaced apart to define a spark gap and with their end walls facing one another, and an insulating member interposed between the end walls of the two electrodes, the insulating member is dimensioned to protrude laterally beyond the perimeter of the end face of at least one electrode for causing the initiation of an arc to generate a sliding arc discharge following a curved path around the laterally protruding part of the insulating member.

Abstract: In an overvoltage arrester composed of two electrodes spaced apart to define a gas spark gap presenting an arc discharge region, and a spacer member of insulating material interposed between the electrodes and forming with the electrodes the walls of a chamber communicating with the arc discharge region, elements are disposed in the chamber to establish therein a labyrinth gas flow path between the arc discharge region and the spacer member.

Abstract: In an arrester for limiting overvoltages in a low voltage power system and for coupling conductors which are normally resistively separated from one another for lightning protection, which arrester includes at least two electrodes spaced apart to define at least one spark gap forming an arc discharge region, and an insulating member holding the electrodes in spaced-apart relation, there is provided a chamber adjacent the arc discharge region and having a chamber wall of an insulating material which emits a quenching gas under the effect of heat and which is provided with at least one outlet aperture through which the gases emitted under the effect of the heat generated during arc discharge can escape.

Abstract: The tape splicing machine comprises feed means for intermittently feeding adhesive tape from a continuous roll to a mobile head provided with sucking and blowing means and with cutting means. Said feed means comprise a grooved wheel partly wrapped by the tape and a support and guide element provided with sucking and blowing means. Said element is moved periodically to and from the head so as to transfer subsequent portions of the tape from the grooved wheel to the head.

Abstract: In an apparatus for forming a groove which is modulated to present an information track in a signal record carrier having a copper surface portion by cutting such groove into the copper surface portion by means of a cutting stylus, the stylus is formed to present, during cutting, a rake angle of between 10.degree. and 20.degree., and the copper constituting the surface portion into which the groove is cut has a Vickers hardness of between 110 and 300, and preferably between 120-220.