Abstract: A method and an apparatus for manufacturing rigid computer memory disc substrates is disclosed wherein the apparatus comprises a circular base plate, the base plate being mounted horizontally for rotation about a vertical axis; a plurality of spindles rotatably mounted on motors mounted on the base plate, the spindles extending radially outwardly from the base plate, in equally spaced relationship therearound, the outwardly extending end of each spindle including a fastening means for mounting a rigid disc to be processed thereon; a plurality of work stations spaced around the circular base plate for performing work operations on the discs; and a motor for rotating the base plate so as to convey each of the discs consecutively to each of the work stations.

Abstract: The method of finishing the surface of a disc, such as a disc whereon information is magnetically recorded for use in computers and the like. It involves urging against one side of a rotating disc, a polishing pad having a polishing compound or medium thereon, and simultaneously urging a non-polishing pad against the opposite side of such disc in alignment with the polishing pad. To simultaneously polish the opposite side surfaces of the disc, a second pair of pads (one polishing and one non-polishing) is equiangularly spaced on the disc in relation to the first pair of pads, but the pads of the second pair of pads are reversed so as to cause the finishing process to occur on the disc side not being polished by the first pair of pads. Any desired even numbered pairs of pads may be employed.The polishing and non-polishing pads are caused to rotate relative to and against the respective side of the disc as the disc itself is caused to rotate about its axis.

Abstract: A peripheral controller, designated as a data link processor, is used for linking a main host computer system with a plurality of magnetic tape transport units. Upon receipt of instructions from the main host system, the data link processor will initiate operations for the sending and receiving of data from a plurality of magnetic tape units and relieve the main host system of all housekeeping functions required for data transfers. The data link processor is made up of two units which may be mounted on separate slide-in printed circuit cards. The first unit is a standardized common unit for all types of data link processors and is known as the Common Front End. It provides micro-code storage which is used to effectuate various read, write, control and transfer operations. The second unit is designated as a Peripheral Dependent Board providing the transmission-reception interface to the peripheral magnetic tape units.