Abstract: A transducer for measurement of a current includes a magnetic core, a single U-shaped flat conductor which has two wings, and a crown joining the wings. Each wing has two openings, and the magnetic core passes through the openings. The two wings constitute two conductive branches in thermal contact with one another, and each branch is adapted to carry a component of the current; the current component carried by one branch differs from the current component carried by the other branch. The current components give rise to opposite respective component fluxes in the magnetic core.

Abstract: The current transformer for instruments for measuring electric currents includes a magnetic core that has two cores and an inductive current divider with three parallel current paths. The current dividers form, together with cores, two current transformer stages whose magnetic fluxes mutually cancel one another. In a current transformer for AC currents having a DC component, the ratio of the ohmic resistances of the individual current paths is in direct relation to their transformation ratio.

Abstract: A method and an apparatus for obtaining digital periodic time function signals, and wherein each time function signal is defined by an instantaneous frequency varying in dependence of time within a characteristic period T equal to the period of a first clock signal, includes a generator for generating a second clock signal, period counters for cyclically counting the periods of the second clock signal, a divider for deriving a third clock signal from the second clock signal, and wherein the third clock signal is a subharmonic of the second clock signal, a memory which has a plurality of storage cells for storing groups of binary numbers characteristic of the time function signals, respectively, an address counter for sequentially calling up and reading out the storage cells with the aid of the third clock signal, a logic circuit for enabling the count of one period counter with a predetermined delay with respect to the time of call-up of each corresponding storage cell, and bistable multivibrators for inverti

Abstract: In a method of correcting a signal having a sequence of binary bits modulated on a carrier and followed by demodulation of the signal, and wherein a distortion has been impressed on the signal during passage through a transmission channel, the steps include setting initial threshold values in dependence of initial reception conditions and wherein the threshold values normally vary as a function of time with a bit duration, comparing the demodulated signal several times within the bit duration with the set threshold values, and correcting the initially set threshold values in dependence of later reception conditions following the initial reception conditions.

Abstract: A measuring transformer comprises a measuring conductor carrying the current I.sub.m to be measured, a pre-magnetizing winding which carries a pre-magnetizing current I.sub.v, and a magnetic field comparing means which is exposed to the magnetic field produced by the current I.sub.m and the magnetic field produced by the pre-magnetizing current I.sub.v and is alternately controlled in both directions of saturation. The magnetic field comparing means is a magnetic film which may be anisotropic, operated in the magnetic preferential direction, and have a thickness of at most a few microns. It may be secured to pole shoes of a magnetic core or arranged between a flat measuring conductor and a pre-magnetizing coil of flat cross-section. The measuring transformer can be used as an input transformer in a static electricity meter. In a further embodiment, the output pulses can be obtained directly from the magnetic field comparing means.

Abstract: In an apparatus and a method for recognizing the start of a noise-corrupted received telegram signal, and wherein the telegram signal consists of an information-containing sequence of bits ahead of the telegram signal, thereafter transmitting an intermediate sequence of bits following the preliminary sequence, but still ahead of the telegram signal, wherein the preliminary and the intermediate sequences are correlated with different parts of the preliminary and of the intermediate sequence in a pre-arranged manner, and detecting the pre-arranged manner so as to positively signal termination of the intermediate sequence; recognition of the start of the telegram signal is thereby ensured.

Abstract: A receiving arrangement is provided, to receive audio frequency signals that are transmitted by way of lines of an alternating current distribution network. The audio frequency signals are decoupled from a low or medium voltage level of the network. The currents in one or more phases in such level are detected and the signal is applied to a receiver. The audio frequency signals are decoupled by means of one or more current transformers or voltage transformers and currents or voltages in secondary windings of signal transformers connected thereto are detected. Each secondary winding of the signal transformers with the ohmic resistance thereof and the load resistance thereof, forms a high-pass filter with the lowest frequency to be transmitted as its lowermost frequency. The signal transformer cooperates with an amplifier, summing or subtracting circuit in the receiving circuit.

Abstract: In a security blank which includes a substrate which has two major surfaces, a thermoplastic layer which has a predetermined refraction index and is suitable for embossing thereon a machine-readable authenticity feature in the form of an optical microstructure, and a transparent layer which has a prearranged refraction index for covering and protecting the microstructure, and wherein the prearranged refraction index has a value different from the predetermined refraction index, and the microstructure generates a characteristic diffraction effect from light incident thereonto, the improvement includes a surface of the substrate facing the thermoplastic layer, which has within a region of the microstructure diffuse reflection characteristics of a predetermined magnitude, and wherein the thermoplastic layer is transparent, and wherein the difference between the refraction indexes is sufficiently small, and the magnitude of the diffuse reflection characteristics is sufficiently large, so that the characteristic d

Abstract: A current divider for use in connection with a measurement transducer. The measurement transducer includes a magnetic core, is formed as a substantially flat and longitudinal conductor with two longitudinal slits so as to partition the flat conductor into at least a measurement conductor, and at least two shunts are connected in parallel with the measurement conductor. The shunts define a plane, and the measurement conductor is disposed in the plane between the shunts. The flat conductor has two openings along the longitudinal direction, to receive the magnetic core. One slit communicates with one opening, and the other slit communicates with the other opening.

Abstract: In a housing two ultrasonic measuring transducers are arranged opposite of the two end faces of a test tube. The test tube providing a measuring section penetrates a separating wall and interconnects two distribution chambers of the housing. The fluid to be measured flows through the test tube and influences the transit time of the ultrasonic impulses released and received by the measuring transducers. The test tube provides a constant cross-section of metallic material along the length of the measuring section. The connection between the test tube and the separating wall consists of a nonmetallic material, thus preventing echoes which may penalize the measuring accuracy.

Abstract: In a magnetoresistive current detector, which includes a conductor carrying a current to be measured, which in turn generates an external magnetic field, four bridge elements are connected to one another so as to constitute a Wheatstone bridge. The Wheatstone bridge is adapted to be fed by a supply current from a current- or voltage-source and includes two pairs of ferromagnetic and magnetoresistive thin films which have hard and easy axes, respectively, and each thin film constitutes a respective bridge element. The thin films of each pair are magnetostatically coupled to one another, so that the portion of the supply current flowing in each thin film of each pair generates an auxiliary magnetic field, which has a direction along the hard magnetic axis of the other thin film of the same pair.

Abstract: In a method and an apparatus for enhancing the probability of substantially error-free reception of a signal including a sequence of discrete bits with the aid of a time-variable threshold value, and wherein each bit has a predetermined duration, and the threshold value may change during the bit duration, the steps include comparing at least a selected one of the received bits a multiple number of times with the threshold values, so as to establish the probable validity of the received bits in dependence of the comparison results.

Abstract: A cell which is arranged to allow the transfer of charges between two electrodes, includes two electrically conducting electrodes spaced apart from one another, and a solid dielectric material disposed between the electrodes, and including a certain quantity of carriers of a positive charge trapped therein.

Abstract: In an electronic energy consumption meter using a mark-space amplitude multiplier, including a current-frequency transducer, a first supervisory circuit is coupled to, and supervises the mark-space modulator multiplier, a second supervisory circuit is coupled to, and supervises the current-frequency transducer, and a fault indicator is coupled to the output of each of the supervisory circuits for indicating a fault in the meter.

Abstract: In a measuring process for determining a tariff value for energy consumed, fixed quantity pulses are produced by means of a pulse generator 6 associated with a consumption meter 3. Measurement values which are proportional to the reciprocal of the time intervals between the fixed quantity pulses are summed in a summing means 9. The expectation value P of the power, the quotient of the expectation value P and the mean value P of the power, and the form factor of the load curve, are determined in an evaluation device 11, from the measurement value Z.sub.2 of the summing means 9 and the measurement value Z.sub.1 of the consumption meter 3. The summing means 9 and the consumption meter 3 are connected to the evaluation device 11 by way of a communication channel 10. A microprocessor may be used for determining the reciprocal.

Abstract: A mixture of two to three ingredients, which ingredients may be stored on their own, are used for the manufacture of a thermochrome lacquer. The first ingredient is a compound of heavy metal or noble metal dispersed in a resin base solution, the second ingredient is a sulfur/carbon-covalent compound dispersed in the resin base solution, or in a hardener for the resin base, and the third ingredient, if required, is the hardener. The resin base is related to the hardener, and the metal compound to the sulfur/carbon covalent compound in respective stochiometric ratios. The metal compound is a metal compound of an oxide forming metal sulfide compounds with the sulfide ions, the metal sulfide compounds being irreversibly darkened, or a metal compound of an inorganic anion, or a metal compound of a monocarboxylic acid, or a metal compound of a dicarboxylic acid. The resin base consists of a prepolymerizate of a methacrylic acid, or of a glycide lather, and the hardener consists of a diol or an amine.

Abstract: A current-measurement transducer comprises a thin-film magnetic coil for passing an alternating premagnetizing current, generating an alternating premagnetizing field, and a magnetic-field comparator which includes first and second magnetic anisotropic films disposed in respective substantially parallel planes. Each film is composed of ferromagnetic and magnetoresistive material, and defines a magnetic easy axis, along which the film is relatively easily magnetizable, and a magnetic hard axis, at right angles to the easy axis, along which the film is harder to magnetize than along the easy magnetic axis. A non-magnetic and electrically at least poorly conducting layer separates the films, and the films are coupled to one another sufficiently tightly so that a current passing in one magnetic film generates an auxiliary magnetic field along the hard magnetic axis of the other magnetic film.

Abstract: An apparatus adapted for thermally erasing or changing machine readable optical markings previously entered on a carrier of thermoplastic material which has two major sides, and wherein the optical markings cause a predetermined modification of any light rays impinging on the optical markings by either diffraction or refraction, include a erasing device adapted to be located on one major side of the carrier, for erasing or changing the markings, a reading device, operative during operation of the erasure device, and including at least two light sensors adapted to be located on the other major side of the carrier, so as to check the erasure or change of the markings effected by the erasing device. The light sensors provide output signals of respective opposite polarities following erasure or change of any one of the markings.

Abstract: To transmit signals over an alternating current power distribution network, the network load parameters are modulated by means of non-linear elements or by varying the characteristics of components by electrical action dependent on a reference signal. A reference current, a capacitor voltage, a correction signal for varying an inductance of the network load, the network voltage, an external current source, the total current flowing through a divided network load or its zero passages and those of the network current form the reference signal. The network load is connected by a transformer to the network and comprises at least one series-resonant circuit.

Abstract: A measuring transformer comprises a measuring conductor carrying the current I.sub.m to be measured, a pre-magnetizing winding which carries a pre-magnetizing current I.sub.v, and a magnetic field comparing means which is exposed to the magnetic field produced by the current I.sub.m and the magnetic field produced by the pre-magnetizing current I.sub.v and is alternately controlled in both directions of saturation. The magnetic field comparing means is a magnetic film which may be anisotropic, operated in the magnetic preferential direction, and have a thickness of at most a few microns. It may be secured to pole shoes of a magnetic core or arranged between a flat measuring conductor and a pre-magnetizing coil of flat cross-section. The measuring transformer can be used as an input transformer in a static electricity meter. In a further embodiment, the output pulses can be obtained directly from the magnetic field comparing means.