Abstract: Reading and recording apparatus for cards having at least one magnetic track in which the card is held stationary and a magnetic head suspended in gimbals is utilized to read or write upon the card.

Abstract: A measuring transformer arrangement is provided for a fluid-insulated high-voltage installation with metal encapsulation carrying several conductors. The measuring transformer arrangement includes at least one conducting or semiconducting tube surrounding each conductor whereat at least one current transformer core with a system of secondary windings mounted on it is attached on the outside of the tube. The tubes are connected with each other and are attached to the metal encapsulation.

Abstract: An improved voltage transformer for use in a gas insulated or liquid insulated high voltage switching installation enclosed within a metal encapsulation and carrying several conductors, in which each conductor is surrounded by a tube which is conductive at least on its surface which faces the conductor with the tubes connected to each other through attachment means which attach them in an insulated manner to the metal encapsulation. The resulting arrangement causes each tube together with the conductor within it to form a high potential capacitor which can be coupled in series with a low potential capacitor to form a voltage divider with the voltage taken off the low potential capacitor and used to provide an indication of the voltage present on the conductor. Tubes which are plastic with conductive coatings and metal tubes are disclosed with the tubes fastened to at least one support disk of insulating material which is then attached to the metal encapsulation.

Abstract: A voltage measuring device for use with an encapsulated, high-voltage switching installation including an inner conductor within a grounded metallic outer tube. The measuring device includes means for widening the outer tube, thereby providing a space for locating certain portions of the measuring device. Positioned in the space formed by the widening means is an auxiliary electrode means, insulated from the outer tube, which forms a capacitor with the inner conductor. Measuring means and servo-indicating means are connected in various ways to the capacitor formed by the auxiliary electrode means and the inner conductor. These measuring means respond to variations in the electrical characteristics of the capacitor thus formed to thereby give an indication of the voltage of the inner conductor.

Abstract: A voltage measuring device is described which is suitable for application to encapsulated, high-voltage switching installations which include an inner conductor surrounded by a grounded metallic outer tube. The device utilizes the fact that an electric field exists between the inner conductor and metallic outer tube. It includes means for widening a portion of the outer tube to thereby form a space for locating certain portions of the measuring device. The device itself includes an electro-optical component, such as a Kerr or Pockels cell which is positioned in the space defined by the widening means, at a distance from the inner conductor which is approximately equal to the distance that the outer tube is located from said inner conductor. A metal layer is positioned on that side of the electro-optical component which is away from the inner conductor. The metal layer is electrically connected to the grounded, metallic outer tube.