Abstract: A velocity servo system for a disk drive, the servo system being responsive to digital signals and generating a control signal for moving a read head of the disk drive from a current track position to a commanded track position. The servo system includes a circuit for reading current track address information and servo bursts recorded on a disk in said disk drive and for generating threshold signals when said read servo bursts are of a predetermined amplitude. An appropriately programmed data processing system provides a decoder responsive to the current track address read by the reading means and to the threshold signals for generating a current half track address, a first comparator which compares the current half track address with the commanded track position to generate half tracks-to-go digital data in response thereto; and generates commanded acceleration data in response to the half tracks-to-go data and to successive half track addresses.

Abstract: A magnetic tape reel (10) is illustrated which includes a central hub (A) and a back flange (B) and a front flange (C). The central hub (A) is symmetrical about a plane represented by line (26) which is normal to the reel axis (28) passing through the axial center of the reel. Through a section of the central hub there is provided a compression resisting Y-shaped section (D) that includes a transversely widened web stem (44) which carries an enlarged compression-resisting body at the top thereof which carries the tape winding ring (12). The compression-resisting body includes a shoulder (46) and a Y-shaped crossarm (48). Winding of tape on the tape winding ring (12) causes compression forces which are effectively resisted by the structure afforded through the Y-shaped web section (D). Attachment between the back flange (B) and the central hub is had between a ledge supporting surface (78) and a side of the shoulder (46b).

Abstract: A standard magnetic tape storage reel in combination with an insert for decreasing the tape storage capacity of the reel. The insert fits over the hub of the reel and is welded to the flanges. The insert is of integral construction and includes an inner circular rim portion which has an opening dimensional to fit over the reel hub, an outer circular rim portion which forms the new hub about which the tape is wound, a flat central web rib portion which extends between the outer and the inner rim, a plurality of radial ribs extending on both sides of the central web rib portion between the inner and outer rim portions, and a circumferential rib, concentric with the rim portions, located on either side of the web integrally connecting the radial ribs and the central web rib portion.