The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 02, 1998
Filed:
Oct. 13, 1994
Hiroya Abe, Hiratsuka, JP;
Hideo Nishijima, Katsuta, JP;
Kouji Kaniwa, Yokohama, JP;
Kouji Minabe, Katsuta, JP;
Yoshio Narita, Katsuta, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
A tracking method and apparatus used in a helical scan magnetic recording/reproducing system is based on an automatic tracking control using an envelope detection signal of a reproduced signal. The tracking apparatus is provided with a circuit for controlling the rotation speed of a capstan motor which transports a magnetic tape, a level comparing circuit for making the comparison for the level of an envelope signal of the reproduced signal, a circuit for applying a predetermined deviation to the rotation speed in accordance with the result of comparison, a circuit for detecting a steady speed deviation between a recording apparatus and a reproducing apparatus from a speed deviation signal generated in the process of the automatic tracking control, and a circuit for correcting the speed deviation.