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:
Jan. 23, 1979
Filed:
Jul. 01, 1977
John C Beery, Locust Grove, VA (US);
Harvey L Huston, Fairfax, VA (US);
Signature Systems, Inc., Springfield, VA (US);
Abstract
An improved method and apparatus for reducing wow and flutter associated with recording devices are disclosed. Two input signals containing useful information and a constant reference signal are recorded and reproduced by a three channel recording and reproducing system. The reproduced signals contain, in addition to the recorded signals, frequency deviations caused by wow and flutter of the recording and reproducing system. Reproduced signals are converted to frequency-dependent voltages and the constant reference signal is subtracted from the reproduced reference voltage to provide a reference error voltage. The reference error voltge is transmitted to a multi-state control circuit in which the reference error voltage cancels the error voltage components of the two reproduced information frequency-dependent voltages leaving only the frequency-dependent information input signal voltages which are then transformed into frequency signals substantially equal to the recorded information signals.