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:
Sep. 20, 1988
Filed:
Oct. 05, 1984
Thomas D Sharples, Redwood City, CA (US);
Michael L Collette, San Francisco, CA (US);
Kelly Quan, San Francisco, CA (US);
George Wong, San Francisco, CA (US);
Otari Electric Co., Ltd., Foster City, CA (US);
Abstract
A synchronizer for synchronizing a slave tape recorder to a master tape recorder. When the speed of the master recorder exceeds 2.5 times the nominal play speed, the synchronizer causes the slave recorder to lag behind the master recorder by an amount related to the speed of the slave recorder. At lower speeds, the synchronizer causes the slave recorder to lock onto the position and speed of the master recorder. The synchronizer employs time-code readers to read time-code on address tracks on the master and slave recorders. The time-code readers produce not only time-code but also clock pulses which are employed to determine the speed of master and slave with high resolution. Both the time-code readers and a resolver employed in the synchronizer are constructed from gate assemblies rather than processors to reduce execution times for the processor in the synchronizer. The resolver is a digital resolver which includes a phase comparator which produces pulses having a width related to the phase difference between indications of the synchronization word in the time-code and polarity to indicate whether the master leads or lags the slave. This signal is applied to a counter which generates a digital error signal based on the phase difference which is employed to control the speed of the slave recorder.