Patents by Inventor Herman Lia

Herman Lia 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: 4761695
    Abstract: To improve recording of data on a magnetic recording medium such as a magnetic tape, amplitudes of write signals supplied to a magnetic head are modified, dependent on distances between edges of the write signals. The modification occurs such that, given a short spacing, a respective write signal has a greater value than given a large spacing. Amplitudes of the write signals are modified in three steps when the GCR method is employed as a writing method for recording the data, distances of the edges of the write signals being capable of assuming three different values.
    Type: Grant
    Filed: September 18, 1986
    Date of Patent: August 2, 1988
    Assignee: Tandberg Data A/S
    Inventor: Herman Lia
  • Patent number: 4547818
    Abstract: High-frequency magnetic bias signals are superimposed on the data signals and are synchronized with the data signals. For the data signals and for the magnetic bias signals in each instance a separate write amplifier with two logic elements is provided which are alternately switched in dependence upon the binary values of the data signals and the magnetic bias signals, respectively. Mutually corresponding logic elements in the write amplifiers are interconnected at the output side via resistances. The magnetic head is connected between the connection points of the resistances. The resistances determine the respective current through the magnetic head. As logic elements preferably integrated NAND circuits without output-side collector resistances are provided.
    Type: Grant
    Filed: September 7, 1983
    Date of Patent: October 15, 1985
    Assignee: Tandberg Data A/S
    Inventor: Herman Lia
  • Patent number: 4479151
    Abstract: Encoded digital information signals are magnetically recorded on a magnetic recording medium with the assistance of a magnetic head to which write current is supplied. As a function of the encoded information signals, a head change is carried out wherein the current applied to the magnetic head is changed from a first current value to a second current value and vice versa. After each head change, an amplitude of the write current is varied in stepwise amounts from the first or second current value, respectively, and wherein the number of steps depends on a chronological spacing of the head changes from one another. Distortions of resulting read signals are reduced given the method and apparatus of the invention.
    Type: Grant
    Filed: March 30, 1982
    Date of Patent: October 23, 1984
    Assignee: Tandberg Data A/S
    Inventors: Herman Lia, Erik Solhjell