Abstract: Improved flexible disk magnetic storage systems and associated sub-assemblies and media are illustrated in the embodiments as comprising a pack of flexible magnetic recording disks stacked for co-rotation at high rpm on a manipulator assembly which includes a pneumatic separator-hub adapted to be shifted axially along the disk array so as to direct an air jet between selected disks and thus "partition" the stack for entry of a transducer assembly.

Abstract: Improved disk pack media for data storage illustrated as comprising a pack of flexible magnetic recording disks perforated for partitioning and adapted for stacking each in a different respective rotational orientation to facilitate partitioning. All disks are hole-encoded in a common pattern, then stacked to dispose each in a unique rotational "misregistration" relative to all others -- thereby opening-up and/or closing-off adjacent "partition bores" and permitting associated automatic apparatus to selectively partition the pack and expose any desired disk-side for operation thereon.

Abstract: Improved flexible disk storage media comprising a pack of flexible recording disks adapted for compact stacking in superposed registration. Each disk is hole-encoded to permit associated disk partitioning apparatus to provide automatic selective partitioning of the pack for selecting a desired disk for the performance of a recording and/or reproducing operation with respect to a surface thereof. Each multiple disk pack is removably contained in a protective jacket during partitioning and transducing operations. The jacket cooperates with automatic jacket-opening means so as to provide for convenient insertion and withdrawal of a disk pack while permitting selective partitioning of the pack while contained in the jacket for the performance of a transducing operation on a selected disk in the pack.

Abstract: Improved apparatus for controlling tape speed in a reel-to-reel magnetic tape transport system. A controllable reel drive motor operates in response to a control signal derived from an accumulated count of reel revolutions so that the driven reel is driven at a varying angular velocity chosen to produce a substantially constant predetermined tape speed as the tape is wound. In order to more accurately maintain a constant tape speed an indication of tape speed error is obtained by measuring and comparing with a reference the elapsed time between the writing and recording of a signal using a magnetic head arranged for read-after-write operation, any resulting tape speed error being employed to change the accumulated count in a direction which reduces the tape speed error.