Abstract: An array of like system modules linked to a common control unit by connect lines, bussed and connected to all the modules by respective removable pin units so that each module address can be generated solely according to which said pin units are not connected.

Abstract: Principal embodiment teaches method and apparatus for fine positioning (centering) of a magnetic recording transducer relative to the concentric tracks of a rotatable magnetic disk having an "embedded" format (i.e., work data and servo data interspersed in alternate sectors along each track -- vs. "dedicated servo tracks"). The servo data sectors comprise repeating groups of servo tracks used to provide coarse and fine radial positioning signals for the transducer relative to the work data tracks.The servo system controls head-positioning carriage means to keep the transducer gap "centered" during Reading and Writing operations using improved fast digital AGC circuit means and also provides timing information (synchronized clock signals, timing-decode) determined by the drive, rather than external means.

Abstract: Principal embodiment teaches method and apparatus for radial positioning of a magnetic recording transducer relative to the concentric tracks of a rotatable magnetic disk having work data and servo data interspersed in alternate sectors along each track. The servo data sectors comprise repeating groups of servo tracks used to provide coarse and fine radial positioning signals for the transducer relative to the work data tracks.The servo system control hard-positioning carriage means [to seek target track and keep transducer gap "centered" during Reading and Writing operations] and also provides timing information (synchronized clock signals, timing-decode) determined by the drive, rather than external means. An "embedded" format, rather than "dedicated", is used for laying down the servo information.