JPS60216678A - Magnetic recording and reproducing device - Google Patents

Abstract

PURPOSE:To provide convenience of recording and reproduction by providing the mode outputting a sound signal reproduced from a lengthwise direction recording track as a reproduced sound and the mode outputting the reproduced sound signal reproduced from the slant track as the reproduced sound. CONSTITUTION:A video/sound signal reproduced from a head 43 is transmitted to a reproducing amplifier 28, an HPF31, an LPF34 and a BPF36 through a switch 24. The luminance component and the chrominance signal component are added by an adder 33 and the reproduced video signal is outputted. The sound signal subject to frequency modulation is outputted via a switch 30. An output from a head 44 is given to a reproducing amplifier 47 through a switch 46. The output is led to BPF48, 49. The output of the BPF49 is inputted to a pilot signal detector 50, which changes over the switch 30 to the position A of after- recording sound reproduction in detecting a pilot signal. The after-recording sound signal passing through the BPF48 is outputted via the switch 30.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a helical scan magnetic recording and reproducing device that records and reproduces video and audio signals by forming diagonal tracks on a magnetic tape using a rotating magnetic head. The present invention relates to a magnetic recording and reproducing apparatus that records and reproduces information on diagonal tracks.

In conventional simple VTRs that use cassette/magnetic tape, video signals are recorded on diagonal tracks using a rotating head, and control signals and audio signals are recorded on two longitudinal tracks provided at both ends of the magnetic tape. is used.

An example of such a cassette helical 'V'TH is shown in FIG. 1ζ. The figure shows an example of a tape loading state in the VTR, in which 1 is a cassette, 2 is a magnetic tape, and 3 and 4 are rotating magnetic heads, which are arranged on a rotating head drum as shown. 9 is a capstan, 8 is a pinch roller, and 8 and 9 feed the tape 2 in the direction of arrow 10 at a constant speed. As a result, the magnetic tape 2 is wound around the surface of the head drum and runs, and the rotation of the rotary head 6.4 in the direction of arrow 11 forms diagonal tracks on the magnetic tape. 5 is a full-width erasing head for the tape, 6 is an erasing head for only audio tracks, and 7 is a recording/reproducing head for audio and control signals.

FIG. 2 is a schematic diagram showing an example of a pattern on a magnetic tape recorded on the VTR shown in FIG. A 12-in-1 field video signal is recorded on the video track on which the head 3 and 4 video signals are recorded using a known azimuth recording method. Further, the audio signal is recorded by the fixed head 7 on the audio track 13 formed in the longitudinal direction at the widthwise end of the tape, and at the same time, the audio signal is recorded on the control track 13 at the other end.
A CTL signal for synchronizing playback is recorded.

On the other hand, in order to reduce the amount of magnetic tape consumed and to make tape cassettes and devices smaller and more compact, the recording trajectory has been made narrower and the magnetic tape running speed has been lowered by increasing the recording density of video signals. It is. However, when the running speed of the magnetic tape is extremely low, it is necessary to ensure sufficient frequency characteristics of the audio signal by the fixed head.For this reason, the composite signal of the video signal and the audio signal is the same. A method of recording and reproducing information using a rotating magnetic head has been considered.

FIG. 3 is a curve diagram showing an example of the frequency band of a video/audio signal when a composite signal of a video signal and an audio signal is recorded by a rotating magnetic head. In the figure, 15 is a low frequency converted color signal band, 17 is an FM modulated luminance signal band, and 1
6 is an FM-modulated audio signal band. Note that this band is just an example, and other combinations may be used. Conventionally, in this type of system, the video signal and audio signal are combined and recorded, so the audio signal is recorded separately. It was impossible to do so.

The present invention provides a rotary magnetic head for recording and reproducing video and audio signals on diagonal tracks.
In order to facilitate recording and reproduction, a recording track for separately recording audio is provided in the longitudinal direction of the tape, and an audio signal reproduced from this longitudinal recording track is output as the main voice again, The present invention provides a magnetic recording/reproducing device having a mode in which an audio signal reproduced from a diagonal track is output as reproduced audio.

FIG. 4 is a schematic diagram showing an example of a magnetic tape pattern according to the magnetic recording/reproducing apparatus of the present invention.

In the figure, 18 is an OTI and control signal recording track, and 19 is a track on which a video/audio composite signal is azimuthally recorded by a rotating magnetic head. 51 is an audio recording track.

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 5 is a block diagram showing an embodiment of an electric circuit for normal recording/playback and audio dubbing of a VTR according to the present invention. In the figure, during normal recording, the recording/reproducing signal switching analog switch 24 is set to recording mode (ReC), and when a video signal is input, a low pass filter (LPF) 20 takes out the luminance signal, and the luminance component of the video signal is extracted. The signal is output, frequency-modulated by an IIFM modulator 21, and added to an adder 22. Further, the color signal component of the video signal is extracted by a band pass filter (BPF) 25, converted to a low frequency by a frequency converter 26 that converts the color signal to a low frequency, and added to an adder 22. It will be done.

On the other hand, the audio signal is frequency modulated by a 7M modulator 27 and added to an adder 22.

As shown in FIG. 3, the audio frequency band 16 falls between the low frequency converted color signal 15 and the frequency modulated luminance signal 17. The output of the adder 22 is sent to the recording amplifier 25, applied to the rotating magnetic head 43 via the Re (H terminal) of the analog switch 24, and recorded on the video tape 45.

Further, during normal playback, the analog switch 24 is switched to playback mode (Play), and the after-recording signal/normal playback signal switching analog switch 5o is switched to the normal playback position N. That is, the video and audio signals reproduced by the rotating magnetic head 43 are transmitted to the reproduction amplifier 28 through the analog switch 24. The output of the reproduction amplifier is bypass filter (HPF) 51, LPF 34, BPF 56
sent to. 31 is an HPF that extracts the frequency-converted luminance component (17 in Figure 3), and this output is sent to the FMam unit 32.
It is input to a total of 32 adders 55. 54 is an LPF that extracts the color signal component (15 in Fig. 3) frequency-converted to a low frequency range.
The color signal returned to its original state by passing through the frequency demodulator 55 is added to the adder 36. The output of 35 is a reproduced video signal. On the other hand, the frequency modulated audio signal (6th
16) in the figure is inputted to the J7M demodulator 57 through the BPF 56 and outputted as an audio signal through the analog switch SO.

In the apparatus of the above type, in this embodiment, in order to enable audio dubbing, a track dedicated to dubbing recording is provided and a fixed magnetic head 44 for dubbing is provided.

During audio dubbing recording, the dubbing recording/playback signal switching analog switch 46 is switched to dubbing position A. picture·
The audio signal separated from the audio synthesis signal is sent to the 7M demodulator 5.
7 and then input to an adder 58. On the other hand, the dubbing audio signal is also input to the adder 38, and the addition level adjuster 39 attached to the adder 38 allows the mixing ratio of the pre-dubbing audio signal and the dubbing audio signal to be freely changed and output from the adder 38. be done.

The output of 68 is input to an adder 40, where a pilot signal from a pilot signal generator 41 is added. Here, as shown in FIG.
5 or less and 10 Hz is selected. Note that the band of this pilot signal may be set anywhere as long as it does not affect the audio signal. The function of this pilot signal will be described when reproducing the post-recording audio signal. The output of the adder 40 is input to a recording amplifier and bias adder 42,
Then, a bias signal is added by the bias signal generator 43. The output of the circuit 42 passes through an analog switch 46 and is sent to a fixed magnetic head 44 for post-recording on the video tape 4.
5 is recorded on the 2 tracks dedicated for dubbing recording.

After recording the audio dubbing signal, when the playback mode is set, the analog switches 24 and 26 are switched to the Play position. The output from the fixed head 44 is connected to a reproducing amplifier 47 through an analog switch 46.

The output of the playback amplifier 47 is the post-recording audio signal (sixth
The band pass filter (BP
F) 4 B and the pilot signal component (52 in Figure 6)
The signal is guided to a band pass filter (BPF) 49 which extracts the signal. Then, the output of the BPF 49 is input to a pilot signal detector 50, and when the detector 50 detects the pilot signal, it switches the output mode switching analog switch 30 to the post-recording audio reproduction position A. Moshi BPF 4
The dubbing audio signal that has passed through B is sent to analog switch 3.
0. In other words, when there is a pilot signal, the mode is such that the dubbing audio signal recorded on the post-recording track is output as reproduced audio from the audio output terminal. This output audio signal is a signal obtained by combining the post-recording audio signal input to the adder S8 and the audio signal reproduced from the original recording track at a desired ratio. On the other hand, when there is no pilot signal, the analog switch 50 is switched to the normal playback position N, and the audio output terminal is connected to the video and
This is a mode in which the audio signal separated from the audio synthesis signal is output as output playback audio.

FIG. 7 is a block diagram of a recording/reproducing section showing an embodiment of a simplified VTR according to the present invention. In the figure, 55 is a cassette for storing a magnetic tape 56, and 57 and 58 are rotating magnetic heads for recording and reproducing video/audio composite signals. The rotating magnetic head rotates at a constant speed in the direction of arrow 64. 60 is a capstan, 59 is a pinch roller, and the tape 56 is pressed against the capstan and the pinch roller, and the tape is fed at a constant speed in the direction of arrow 63 by constant rotation of the capstan. 61 is a videotape full-width erasing head, 62 is an O
Fixed head for recording and reproducing TL control signals, 6
Reference numeral 5 denotes a dedicated fixed head for recording and reproducing the audio dubbing signal of this embodiment.

In the above-mentioned embodiment, it was assumed that the voice was recorded separately, and the voice dubbing was performed, but the invention is not limited to this.Also, it is possible to record the voice after-recording again. In order to do this, it is also possible to provide an erasing head for erasing the track dedicated to post-recording in front of the tape running front of the fixed head 65 dedicated to post-recording.

Similarly, the present invention is not limited to the above embodiments, but can be modified as appropriate within the scope of the claims.

As described above in detail, the magnetic recording/reproducing apparatus of the present invention uses a rotating head to record and reproduce υ video signals and audio signals on diagonal tracks on a magnetic tape, and in this method, it is possible to avoid recording and reproducing audio separately. An output mode that uses a longitudinal track and a fixed head to output the audio signal from the longitudinal recording track as playback audio when reproducing the video signal from the tape, and an output mode that outputs the audio signal from the diagonal track as playback audio. It is equipped with an output mode in which it is output as a signal, and has a great effect in facilitating recording and reproducing in a device that separately records audio as described above.

[Brief explanation of drawings]

Fig. 1 is a configuration diagram of a recording/reproducing section showing an example of a simple VTR using a conventional system, Fig. 2 is a diagram of a recording track pattern on a magnetic tape by the apparatus shown in Fig. 1, and Fig. 5 is a diagram of the apparatus shown in Fig. 1. FIG. 4 is a diagram of a frequency band curve of a video/audio synthesized signal recorded by a rotating head in this embodiment, FIG. 4 is a diagram of a recording track pattern on a magnetic tape according to the present invention, and FIG. Block diagram showing the circuit configuration,
FIG. 6 is a frequency band curve diagram of a pilot signal and an audio signal of a longitudinal audio track in an apparatus according to an embodiment of the present invention, and FIG. 7 is a diagram showing the configuration of a recording and reproducing section of a simple VTR according to this embodiment. It is. 30... Output mode switching switch 55... Cassette 56... Magnetic tape 57.58... Rotating head 59... Pinch roller 60... Capstan 61... Full width erasing head 62...・Control signal head 65...Fixed head for audio recording and playback 66...Tape running direction 64...Rotating head rotation direction

Claims (1)

[Claims] A rotating magnetic head records and reproduces video signals and audio signals on diagonal tracks on the magnetic tape, and a fixed magnetic head records and reproduces audio signals on longitudinal tracks on the magnetic tape, and video signals are transmitted from the diagonal tracks. a first output top that outputs the audio signal reproduced from the diagonal track as reproduced audio while reproducing the diagonal track;
and a second output mode for outputting the audio signal reproduced along the longitudinal track as reproduced audio.