Patent ID: 6268974
Filing Date: 2001-07-31
Classification: G11B

Abstract:
A method for selecting an optimum gain for an amplifier used to amplify readback signals transduced from a magnetic recording disc, comprising steps of:(a) providing a first value of gain to the amplifier:(b) using the amplifier to amplify a readback signal by the first value of gain to generate an amplified readback signal;(c) applying the amplified readback signal to an automatic gain control circuit comprising a variable gain amplifier which operates to apply a variable gain over a selected range to the amplified readback signal to maintain an amplitude of an output signal provided by the automatic gain control circuit at a nominal amplitude, the automatic gain control circuit providing an indication of a magnitude of the variable gain; and(d) using the magnitude of the variable gain from step (c) to determine acceptability of the first value of gain for subsequent use by the amplifier.