Abstract: A system for preventing unauthorized copying of recorded information has a number of independently identifiable storage media holding the information in encrypted form and a number of drives for the storage media, the drives each having a key which decrypts the information on at least one of the storage media. The drives are in communication with a host computer which compares the identities of the storage media with each other and with an authorized list of identities. Should an identity be unauthorized or duplicated, indicating unauthorized copying, the host computer can send a message to the corresponding drive that disables either that drive or the storage medium having that identity. The host computer periodically revises the encryption codes of the control and storage media that are authorized and not duplicated.

Abstract: A drive system for capstan driven magnetic tape rolls in which a power belt is trained around a drive wheel and a pair of belt guides. The belt guides are closely spaced relative to the capstan so that the back side of the belt transfers power to the capstan roller while the inner surface of the belt contacts the drive wheel and belt guides. The angular spacing of the belt guides relative to the capstan roller is such that the angle between the axial centers of the belt guides with respect to the axial center of the capstan roller is as large as practical, thereby increasing the frictional surface transferring power from the drive wheel to the capstan roller.

Abstract: A method of making and of reading markers at control positions on a length of magnetic tape having light-impeding coatings on opposed sides of a transparent tape substrate. Markers are recorded by directing focused beams to control positions along longitudinal areas of the magnetic tape. The beams have an energy sufficient to ablate the coatings, but to leave the tape substrate intact. Raster scanning of the control position provides rectangular markers at prescribed positions. The longitudinal extent of these rectangular markers generally conforms to the ANSI Standard for end of tape and beginning of tape marker patterns, while the transverse extent of the markers is greter than the longitudinal extent.

Abstract: A method of making and of reading markers at control positions on a length of magnetic tape having light-impeding coatings on opposed sides of a transparent tape substrate. Markers are recorded by directing focused beams to control positions along longitudinal areas of the magnetic tape. The beams have an energy sufficient to ablate the coatings, but to leave the tape substrate intact. Raster scanning of the control position provides rectangular markers at prescribed positions. An optical splitting element is used in reading the markers. The element is a heptagonal prism which receives light from a tape drive and forms two parallel, spaced apart beams which are first directed at separate elevations through the markers in the magnetic tape, then converged to the light sensors in the drive. Preferably the optical path through the prism is a path formed by folding a hexagonal prism, with the fold being a reflective surface.

Abstract: A method for fabricating upright pins in a base plate, in a mutually orthogonal relationship with respect to the base plate. A first set of holes is made in a base plate at locations needed within an apparatus such as a tape cartridge. The holes are slightly oversize with respect to pins to be permanently seated therein. A second set of holes, a mirror image of the first set of holes, is made in a pin holder plate, except that the holes are not oversize. The second set of holes is adapted to hold pins in frictional contact therein. Once the pins have been disposed in the second set of holes, the holder plate is made to overlay the base plate with the outwardly facing ends of the pins brought into flush alignment with the back side of the base plate by projection through the base plate, but without the pins touching the base plate. The bottoms of the pins are now welded in place by means of a high pulse-power welding apparatus such as a laser working on the back side of the base plate.

Abstract: Tape path stabilization apparatus for establishing vertical tape alignment from a base with respect to a transducer featuring an axially floating, radially symmetric crown pulley and a tape reel with a downwardly extending annular outrigger rib or boss maintaining contact with the base. The crown pulley will chase tape which loses alignment, tending to center the tape at the peak of the crown. The reel with the annular outrigger will feed or receive tape in a desired vertical height, tending to limit the extent of motion of the floating crown pulley, tending to center the pulley in its range of motion.

Abstract: A method for fabricating upright pins in a base plate, in a mutually orthogonal relationship with respect to the base plate. A first set of holes is made in a base plate at locations needed within an apparatus such as a tape cartridge. The holes are slightly oversize with respect to pins to be permanently seated therein. A second set of holes, a mirror image of the first set of holes, is made in a pin holder plate, except that the holes are not oversize. The second set of holes is adapted to hold pins in frictional contact therein. Once the pins have been disposed in the second set of holes, the holder plate is made to overlay the base plate with the outwardly facing ends of the pins brought into flush alignment with the back side of the base plate by projection through the base plate, but without the pins touching the base plate. The bottoms of the pins are now welded in place by means of a high pulse-power welding apparatus such as a laser working on the back side of the base plate.

Abstract: A tape cartridge for one-half inch magnetic tape having a cartridge configuration which is mechanically interchangeable with an ANSI one-quarter inch cartridge. The newly provided cartridge preserves head placement, access door, end and beginning of tape sensing, tape direction, and an outwardly facing drive pulley, all associated with ANSI one-quarter inch cartridges. The present tape cartridge provides turn idlers in the corners of the cartridge so that a tape path can be established following the inner peripheral walls and regions of the cartridge, but avoiding passing in front of or underneath the drive pulley where interference would occur.

Abstract: A method for making endless metallic ribbon drive belts for tape cartridges. Metal is electroformed on a steel ring sandwiched between two non-conductive discs. After removal from the steel ring, the plated ring is thinly coated with an elastomeric coating resulting in a compound belt having a low coefficient of elasticity in the base belt and a high coefficient of friction in the coating.

Abstract: Drive belts for tape cartridges featuring a base belt of low coefficient of elasticity with an elastomeric coating having a high coefficient of friction. Three examples of such belts are: (1) polyimide or polyester film base belts with a thin elastomeric film coating; (2) nickel, copper or steel base belts with a thin elastomeric film coating and (3) spirally wound filaments of high modulus of elasticity within an elastomeric matrix having a low modulus of elasticity, the filaments forming the base belt and the elastomeric matrix forming the coating on the base belt, holding the spiral loops in place.

Abstract: A web guide system wherein misalignment of take-up and supply rolls relative to a reference surface may be compensated without tape distortion by a crown pulley and an adjacent concave web guide. The concave web guide is a fixed, flangeless post about which the web is partially wrapped. The web tends to be self-centering in the concave curved portion of the guide. Tape is fed from a roll to the concave guide and then to the crown pulley of minimum radius which is mounted for axial as well as rotational motion. Pulley axial motion promotes equal edge tension and completes web self-alignment. Final axial alignment without edge pressure is accomplished by fixed tape edge-guides in the region of the head.

Abstract: A tape cleaner head that has an arcuate surface around which tape is wrapped. The body of the cleaning head has an opening formed therein, the opening being shaped so as to form first and second knife edges at a point where the arcuate surface is in contact with the tape. The knife edges provide scraping surfaces to the tape regardless of the direction of travel of the tape over the cleaning head to thereby remove foreign particles from the tape surface to prevent signal disturbance and form a cavity to entrap the particles and remove them from the system.

Abstract: A dual magnetic tape cartridge includes a first reel-to-reel tape wound between two coplaner hubs. A tape loop, extending between the hubs, is guided along a first path and across a tape head access opening. The second tape, in belt form, is guided along a second path and across the tape head access opening at a different level. A drive belt, frictionally engaging first tape peripheries on the hubs, is entrained over portions of a forward drive roller and over portions of two spaced rear idlers. The second tape is entrained over slightly smaller diameter portions of the drive roller and over other portions of the rear idlers to thereby also function as a tensioning belt for the drive belt, causing greater tension in drive belt portions engaging the first tape on the hub acting as the takeup hub than in other belt portions engaging tape on the other hub.

Abstract: Disclosed is a peripheral belt drive tape transport system wherein an endless loop drive belt, which is relatively stiff compared to the tape, peripherally drives tape wound supply and take-up hubs to transfer tape from one to the other and maintain a tension in the tape. The drive belt is supported by non-compliant guide means including a plurality of belt guide members, and has first and second portions extending in curved paths between the peripheries of said guide members while intermediately engaging the peripheries of the tape wound on the supply and take-up hubs respectively. The guide members have corresponding portions at first and second levels, the corresponding diameters of which afford different mechanical advantages. The drive belt engages the guide members at the first level. An endless tensioning belt engages the guide members at the second level for establishing a differential in tension between the first and second portions of the drive belt so as to produce a tension in the tape.

Abstract: A dual magnetic tape cartridge includes a first reel-to-reel tape wound between two coplaner hubs. A tape loop, extending between the hubs, is guided along a first path and across a tape head access opening. The second tape, in belt form, is guided along a second path and across the tape head access opening at a different level. A drive belt, frictionally engaging first tape peripheries on the hubs, is entrained over portions of a forward drive roller and over portions of two spaced rear idlers. The second tape is entrained over slightly smaller diameter portions of the drive roller and over other portions of the rear idlers to thereby also function as a tensioning belt for the drive belt, causing greater tension in drive belt portions engaging the first tape on the hub acting as the takeup hub than in other belt portions engaging tape on the other hub.