Method and apparatus for amplitude compensated write equalization.

摘要

The write-equalised recording circuit has a write head for receiving a flow of current into a magnetic field, having a polarity which is a function of the current direction. A write current source supplies to the write head a current (IW) representative of a data stream to be written onto the magnetic tape. An equalisation current source supplies to the write head an equalisation current (IEQ) for varying the amplitude of write equalisation pulses. The write and the equalisation current sources together supply to the write head current representative of data to be written onto the magnetic tape. A controller regulates current flow from the current sources through the write head, and introduces write-equalisation pulses into the current applied to the head having amplitudes different from those representative of write data. The controller has a converter for changing the data stream into write current switching control signals and equalisation current switching control signals, which govern respective switches.