Abstract: Current testing/measuring apparatus 10 comprises a flexible member 12 having a first end 14 and a second end 16. In use, the flexible member 12 is arranged to locate around a conductor 11 carrying a current to be measured. In particular, the current measuring apparatus 10 comprises a Rogowski coil. The ends of the flexible member 12 are coupled together in use but a gap is created between the ends. This distance can generate errors in the current measurement and the present invention provides compensation means 28 in the form of a compensation windings. The compensation windings comprise a planar spiral conductor provided on a printed circuit board to compensate for the separation distance between the first end and the second end.

Abstract: A protective cover for an optical disk such as a CD. The cover includes a flexible and transparent base portion for covering one side of the optical disk. A first retaining portion is affixed to the top of the base portion so as to define a pocket for snugly receiving and frictionally retaining a portion of an optical disk. A second retaining portion is affixed to the top of the base portion at a distance from the first retaining portion. The second retaining portion defines another pocket for receiving and retaining another portion of the optical disk. Since the cover is transparent and snugly receives the optical disk, digitally encoded data may be readily obtained from the optical disk with conventional equipment, like a CD player, while the cover is positioned over the disk.