Patent ID: 7672076

Claim:
A servo writer for writing servo signals onto corresponding servo bands of a magnetic tape, the servo writer comprising: a magnetic tape traveling system including a supply reel and a take-up reel, the magnetic tape traveling system for traveling the magnetic tape by taking up the magnetic tape being fed from the supply reel with the take-up reel; a DC erase head for magnetizing at least the servo bands in one direction along length of the magnetic tape, while being in contact with the traveling magnetic tape; a servo signal write head for writing the servo signals onto the corresponding servo bands by magnetizing the servo bands in a direction opposite to the one direction, while being in contact with the traveling magnetic tape, the servo signal write head being provided downstream of the DC erase head in a traveling direction of the magnetic tape; a servo signal read head for reading the servo signals that has been written onto the corresponding servo bands, while being in contact with the traveling magnetic tape, the servo signal read head being provided downstream of the servo signal write head in the traveling direction of the magnetic tape; and a control device for controlling a recording current supplied to the DC erase head based on outputs read from the servo signals by the servo signal read head.