Patents by Inventor Al Fischler

Al Fischler has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 4894734
    Abstract: Method and apparatus for providing constant density recording is described. A single set of reconfigurable electronics is employed to control the write frequency for a plurality of frequency zones on a magnetic storage disk. The reconfigurable electronics include means for selectively switching a frequency response determining element within a common channel. Switching is controlled by a digital signal provided by a disk file control microprocessor, avoiding the necessity of mechanical linkages and/or changes in spindle rotation rate. The plurality of zones need not be of equal radius in width but the recording frequency within each zone is fixed throughout that zone. Zone selection is under the control of a disk file control microprocessor which produces a digital code to appropriately configure the electronics for the particular zone. Zone switching is done only when a seek across a zone boundary occurs so that no access time penalties result.
    Type: Grant
    Filed: May 15, 1987
    Date of Patent: January 16, 1990
    Assignee: Maxtor Corporation
    Inventors: Al Fischler, Ross Wilson