Abstract: The present invention comprises selectively locating electrical shorting rings on the male section of an optical cable connector. The particular locations of the rings chosen is commensurate with the length of the cable and provides a basis for amplifying the signals being transmitted along the optical cable. On the female section of the cable connector there are electrical contact devices which can be shorted by the rings on the male section if such rings are present. There is a selectable amplifier circuit connected to the optical cable and the contact devices, and depending upon which contact devices are shorted the amplifier circuit provides the proper amplification to the optical signals which are being converted into electrical signals.

Abstract: The present invention is a method and apparatus for passive generation of magnetic bubbles in thin layers of magnetic materials, such as garnets, and uses specially designed permalloy elements which with the rotation of an in-plane magnetic field act to generate magnetic bubbles over a wide range of bias magnetic field values. The design of a special permalloy element includes an angular portion and a contiguous remaining portion having a large surface area relative to the angular portion. Pulsing of the in-plane rotating field to higher field values as it passes through a predetermined orientation with respect to the angular portion generates magnetic bubbles in a controllable manner for fixed values of the bias field.

Abstract: A tool for molding damp sand or other capillarily held insoluble granular material is disclosed. The tool is capable of forming a channel in a mound of material or removing a block of material from the mound. The disclosed mold of the preferred embodiment has flexible walls which can be moved back and forth to prevent adhesion of the granular materials to the walls of the mold and to facilitate easy removal of the mold.