Minnesota Mining and Manufacturing Company

Marshall R Brookhart

Robert S Bradford

Bennett G Dy

Thomas J Worden

Fredrick J Hodge

An automatic track following feature for use with a helical video recorder is disclosed which enables reproduction of video fields at normal speeds, fast and slow forward and reverse speeds, and at stop motion, wherein a mechanism for moving a playback head transverse to the helical tracks on a magnetic tape is provided in order to enable the head to remain centered on the track regardless of tape speeds and directions of movement. A head position control signal is generated for driving the head positioning mechanism based on a comparison of a signal based on the instantaneous tape speed with a reference speed indicating signal.

Automatic track following feature for helical video recorder

A head positioning transducer is disclosed for use with a rotating drum assembly for scanning a magnetic tape along a plurality of adjacent helically positioned record tracks, wherein the transducer includes a permanent magnet field assembly and a drive coil positioned adjacent thereto mounted on a cantilevered beam, at one end of which a playback head is mounted, such that a drive current supplied to the coil produces a field which interacts with the field of the magnet, causing a force on the coil and beam, resulting in controlled movement of the head transverse to the record tracks.

Head positioning transducer for helical scan video reproducer

A recorder for storage and retrieval of digitized signals on a single track of a suitable record medium is disclosed. The recorder includes networks for partitioning digitized signals into successive frames, each of which preferably contains a plurality of alternate data words and parity words, followed, at the end of each frame by an error check code word and a sync word. The parity words of a given frame are generated from data words of other frames sufficiently spatially remote from the given frame to minimize the probability that a single drop out or other defect in a record medium will, upon playback, cause the loss of data associated with both the given frame and the other frames. During playback, each frame is checked for errors, and if found, corrected data words are reconstructed from the parity words and data words of the other frames and are inserted in the data stream in place of the erroneous data words.

Single track digital recorder and circuit for use therein having error

A recorder for storage and retrieval of digitized audio signals on a single track of a suitable record medium is disclosed. The recorder includes networks for partitioning digitized audio signals into successive frames, each of which preferably contains a plurality of alternate data words and parity words, followed, at the end of each frame by an error check code word and a sync word. The parity words of a given frame are generated from data words of other frames sufficiently spatially remote from the given frame to minimize the probability that a single drop out or other defect in a record medium will, upon playback, cause the loss of data associated with both the given frame and the other frames. During playback, each frame is checked for errors, and if found, corrected data words are reconstructed from the parity words and data words of the other frames and are inserted in the data stream in place of the erroneous data words.

Growing community of inventors

Thousand Oaks, CA, United States of America

Marshall R Brookhart