Magnetic tape dimensional instability compensation by varying recording head azimuth angle

摘要

An apparatus and a method of recording and reading data to and from a multi-track magnetic tape utilize a multi-transducer magnetic head that is able to change its azimuth angle relative to the magnetic tape to compensate for variations in tape width due to sources of dimensional instability, such as age-related tape shrinkage. In one embodiment, the magnetic head contains at least eight write/read pairs positioned between two servo readers. Each servo reader includes a servo read transducer. During the original recording operation, the magnetic head is positioned at a write azimuth angle, for example, twenty degrees, such that a small change in the azimuth angle can compensate for age-related tape shrinkage. A read operation includes aligning two servo read transducers to two recorded servo tracks by laterally moving the magnetic head and changing the azimuth angle of the magnetic head to a read azimuth angle. In the preferred embodiment, the lateral movement of the head aligns the top servo read transducer to a desired servo track. Then, the magnetic head is pivoted about the top servo read transducer until the bottom servo read transducer is aligned to an adjacent servo track. The re-recording operation includes recording new data into the recorded tracks using the magnetic head that is positioned at the read azimuth angle.