Patent ID: 7190551

Claim:
A composite magnetic head comprising: a DC-erasing head, which is slidably contact with a driving magnetic tape, and which DC-erases a servo band of said magnetic tape in such a manner that the direction of the magnetization of said servo band the servo band is directed towards one direction of the lengthwise direction of said magnetic tape; a servo writing head, which is slidably contact with said magnetic tape, and which writes a servo signal thereon so that the direction of the magnetization of the servo band is directed toward the reverse direction to the direction directed by the DC erasing head; and an AC-erasing head, which is contact with said magnetic tape, and which AC-erases the magnetization of the data band of said magnetic tape; said servo writing head and said AC-erasing head being provided at downstream of the driving magnetic tape relative to the DC-erasing head, and said DC-erasing head, said servo writing head and said AC-erasing head being unified with each other.