Hitachi, Ltd.

Hiroyuki Torii

Hideo Nishijima

Katsuyuki Watanabe

Kouji Kaniwa

Hiroya Abe

Toshio Nakamoto

Hitoshi Akamine

Kuniaki Miura

Eiji Moro

An apparatus for recording/reproducing video and audio signals on/from a recording medium includes a first and second tuner which receive a video signal of a first and second format transmitted by broadcasting, respectively; a recorder which records the video signal of the first format from the first tuner on the recording medium; a reproducer which reproduces the video signal of the first format from the recording medium; and a decoder which decodes the video signal of first format from the reproducer and converts the decoded signal to another video signal of the second format. A switching circuit is provided which selects one of the another video signal of the second format and the video signal of the second format as a selected video signal, and a video output terminal outputs the selected video signal through an on-screen display unit.

Digital/analog compatible video tape recorder

A helical scanning video tape recorder for recording and reproducing video signals and audio signals to/from a magnetic tape. The video tape recorder includes an analog signal reproducing mode in which an FM luminance signal and a down-converted chrominance signal are reproduced from the magnetic tape by a pair of magnetic heads having a first azimuth angle and an FM audio signal is reproduced from a deep layer of the magnetic tape by a pair of magnetic heads having a second azimuth angle, and a digital signal reproducing mode in which a digital signal is reproduced from the magnetic tape by the pair of magnetic heads having the second azimuth angle. The digital signal is converted into a signal having a frequency in a frequency band higher than a frequency of the FM audio is signal. The video type recorder also includes a recording mode detector and a controller.

A VTR compatible with the current analog VTR and capable of recording and reproducing digital signals, determines the presence or absence of recorded digital signals and selects an operating mode for recording and reproducing in accordance therewith.

A VTR compatible with the current analog VTR and capable of recording and reproducing digital signals identifies the type of a tape cassette by the presence or absence of a cassette identification hole formed in a digital recording tape cassette determines tape speed for a recording mode on the basis of the ratio between the frequency of a control signal and the rotating speed of a capstan motor, determines the presence or absence of recorded digital signals through the synchronous detection of reproduced output, and decides the mode for recording and reproducing on the basis of those decisions. Thus, the automatic discrimination between the analog mode and the digital mode can be achieved and erroneous operations, such as an erroneous erasing operation can be prevented.

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.

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Hitachinaka, Japan

Hiroyuki Torii