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. 18, 1977
Filed:
Oct. 31, 1975
David W Osburn, Kokomo, IN (US);
General Motors Corporation, Detroit, MI (US);
Abstract
A preamplifier circuit for a tape player includes a voltage-follower transistor which is operable when turned on to establish the output bias voltage of the preamplifier circuit at substantially a reference voltage. In turn, a voltage divider network develops the reference voltage coincident with energization of the tape transport mechanism. Due to the inertia of the tape transport mechanism, the speed of the tape remains below that necessary for undistorted operation during a start-up time period immediately following energization of the tape transport mechanism. An RC network is responsive to development of the reference voltage to provide a time delay such that the voltage-follower transistor is prevented from turning on until after expiration of the start-up time period. Thus, the output bias voltage of the preamplifier circuit is not established until the tape speed is sufficient to permit undistorted operation.