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:
Feb. 17, 1981
Filed:
Oct. 18, 1978
Dietmar Pfefferkorn, Hemsbach, DE;
BASF Aktiengesellschaft, Ludwigshafen am Rhein, DE;
Abstract
A method and apparatus for measuring the electroacoustic properties of magnetic tapes by means of recorded test signals of varying frequency and amplitude, wherein measured values of the reproduced signals which depend on the biassing current and correspond to predetermined parameters are obtained; for each of the relevant values of the biassing current the amplitude of the test signal to the recorded is varied until the predetermined value of the reproduced signal is attained, and the measured value of the reproduced signal obtained in this way is registered, an amplitude-modulated test signal is recorded and, by means of a test programming unit and upon the attainment of a parameter value which controls this programming unit, the relevant measured value of the reproduced signal to be determined is transmitted to an intermediate storage device for further evaluation and the biassing current is varied in order to determine the next value to be measured.