Method and apparatus for determining head parameter for helical scan recorder

A helical scan recorder apparatus which records information on a magnetic tape, the magnetic tape being transported in a tape path between a supply reel and a take-up reel in the helical scan recorder, the recorder apparatus comprising:

• a tape system for conducting a tape extraction operation for extracting the tape into the tape path;
• means for imparting linear velocity to the tape;
• a rotating drum upon which a plurality of heads are adjustably mounted, the plurality of heads including a first head for recording information on the tape and a second head for reading servo information from the tape;
• a supply reel sensor for determining a degree of supply reel rotation;
• a take-up reel sensor for determining a degree of take-up reel rotation;
• a processor which uses the degree of supply reel rotation obtained from the supply reel sensor during the tape extraction operation and the degree of take-up reel rotation obtained from the take-up reel sensor during a tape rewind operation, and which uses servo information on two adjacent tracks of the tape during a read-after-record operation, to adjust positioning of at least one of the heads of the helical scan recorder.