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:
Dec. 24, 1991
Filed:
Apr. 06, 1989
Eiji Moro, Katsuta, JP;
Hitoshi Akamine, Takasaki, JP;
Hiroyuki Torii, Katsuta, JP;
Kuniaki Miura, Ibaraki, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
A magnetic recording and reproducing apparatus having a first recording mode and a second recording mode in which a luminance signal of a video signal is converted into FM luminance signal related to a first carrier frequency and to a second carrier frequency so as to be recorded on a magnetic tape includes a discriminating device or discriminating a recording mode in which an FM luminance signal reproduced from a magnetic tape so as to be supplied to a playback circuit has been recorded. The signal discriminating device includes an automatic gain control (AGC) circuit for absorbing a dispersion of the reproduced signal, a discrimiating circuit having a first band-pass filter and a second band-pass filter for processing an output from the AGC circuit so as to discriminate the first and second modes, a detecting circuut to which the reproduced signal is supplied in a parallel fashion with respect to the AGC circuit such that an amplitude of the signal is detected and is then compared with a predetermined value so as to obtain noise information, and a latch circuit for latching an output from the discriminating circuit such that in response to the noise information from the detecting circuit, a previous value of the outpt from the discriminating circuit is held, thus producing a discrimination output of the discriminating device.