Abstract: A multi purpose capacitive sensor suitable for indicating close proximity of a person to a surface along a large-size truck as well as along a medium-size painting or a pocket-size mobile phone is disclosed. The sensor comprises a voltage measuring device provided with a signal ground connected to a first pole of an oscillating voltage source that has a second pole connected to a signal input of the voltage measuring device. This input has a first capacitance to earth and a second capacitance to the signal ground. A third capacitance is exhibited to earth by the second pole of said voltage source. According to the invention, a prebias component is connected between the second pole of the voltage source and the signal input of the voltage measuring device.

Abstract: A multi purpose capacitive sensor suitable for indicating close proximity of a person to a surface along a large-size truck as well as along a medium-size painting or a pocket-size mobile phone is disclosed. The sensor comprises a voltage measuring device provided with a signal ground connected to a first pole of an oscillating voltage source that has a second pole connected to a signal input of the voltage measuring device. This input has a first capacitance to earth and a second capacitance to the signal ground. A third capacitance is exhibited to earth by the second pole of said voltage source. According to the invention, a prebias component is connected between the second pole of the voltage source and the signal input of the voltage measuring device.

Abstract: A security system comprises a signal transmitter (1) with a first sensor (2) for conveying status information to a receiver (3) via a telecommunication channel (4), the signal transmitter being preferably built into a telephone set and the telecommunication channel preferably comprising a subscriber line in a regular telephone network. A second sensor having a higher sensitivity than the first sensor, is arranged to be influenced by the same alarm situation as the first sensor to transmit alarm information to the receiver via the telecommunication channel, and a restoring circuit (6) comprising time measuring components (7, 8) with an activation input (9) connected to the second sensor is, within a time slot of a predetermined length arranged for the transmittal of the status information and the alarm information, arranged to always transmit restoring information regarding the alarm information to the receiver.

Abstract: A touch control switch suitable for fluorescent lighting, or reactive load, as well as incandescent lighting, or resistive load, installations without modification to the control circuit. The control circuit is connected between the lamp load, either resistive or reactive, and the supply circuit in the lighting installation for alternating current and comprises a semiconductor switching element, such as a TRIAC, having a gate electrode. A counting circuit with a forward stepping input and a digital control output is connected to the gate electrode of the TRIAC via a trigger pulse generating circuit for controlling the conduction of the TRIAC in accordance with the condition of activation of the digital control output. A control pulse shaping circuit has its output connected to the forward stepping input of the counting circuit and first and second input terminals connectable to a touch sensitive impedance, such as a manually controllable capacitive reactance, to enable turn on or activation of the lamp load.

Abstract: A touch control switch suitable for connection between a lamp load and a supply circuit in a lighting installation for alternating current and comprising a semiconductor switching element with a gate electrode, a counting circuit with a forward stepping input and a digital control output connected to the gate electrode of the semiconductor switching element via a trigger pulse generating circuit for controlling the conduction of the semiconductor switching element in dependence on the condition of activation of the digital control output, and a control pulse shaping circuit having an output connected to the forward stepping input of the counting circuit and a first and second input terminal for connection respectively to a first and second terminal of the supply circuit via a touch sensitive impedance. The control pulse shaping circuit comprises a clipper stage with a clipping level controlled by a first voltage-level detector circuit.

Abstract: A touch control switch suitable for connection between a lamp load and a supply circuit in a lighting installation for alternating current and comprising a semiconductor switching element with a gate electrode, a counting circuit with a forward stepping input and a digital control output connected to the gate electrode of the semiconductor switching element via a trigger pulse generating circuit for controlling the conduction of the semiconductor switching element in dependence on the condition of activation of the digital control output, and a control pulse shaping circuit having an output connected to the forward stepping input of the counting circuit and a first and second input terminal for connection to a first and second, respectively terminal of the supply circuit via a touch sensitive impedance.

Abstract: A two-terminal network includes a transistor which is arranged to switch from a low-ohmic to a high-ohmic state when a predetermined value of a potential drop across a collector-emitter path of the transistor is exceeded; a regenerative threshold circuit arranged to disconnect a base current to the transistor the predetermined value of the potential drop is exceeded.

Abstract: The invention relates to an alphanumeric terminal comprising a text generator and a display unit with a signal input connected to the text generator and a cathode-ray tube screen arranged to display a plurality of lines with an alphanumeric information generated by an intensity modulation of a line raster on the cathode-ray tube screen in correspondence to a digitally coded information stored in the text generator, the text generator comprising an alphanumeric character generator with a data input and a text memory arranged to store the digitally coded information for generating said lines with alphanumeric information and connected to the data input of the character generator.