JPH0489605A - Recording and reproducing device - Google Patents

Abstract

PURPOSE:To reduce scale by arranging respective compressed audio signals without being superimposed and unifying reproducing processing systems into one system by adjusting an inter-gap distance between a recording format and a stagger head and reducing time width for one block of the time base compressed audio signal rather than recording start time difference between adjacent tracks. CONSTITUTION:A stagger head 1 scans the surface of a magnetic tape 4 in an arrow direction, a video signal recording track 2 is formed and continuously, a time base compressed audio signal recording track 3 is formed. In the case of recording, the rotary stagger head 1 records every three tracks and timing is shifted, however, only for time difference corresponding to an inter-gap distance (d) between respective head chips. Then, this time difference becomes recording start time difference DELTAt between adjacent tracks. In this case, since time width tA of the time base compressed audio recording signal is set shorter than the recording start time difference DELTAt, the audio signals reproduced by the stagger head 1 are not superimposed but become sequential signals. Thus, the reproducing system of processing audio signals, which are recorded while dividing the channels, can be formed as one channel.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a multi-channel recording helical recording/reproducing apparatus.

BACKGROUND ART In order to record and reproduce a wideband signal such as a video signal, a method is used in which the signal is divided into a plurality of channels and recorded in order to reduce the frequency band of the circuit system. however,
As the number of channels increases, the number of head chips increases, so in order to mount the rad more efficiently in space, a configuration called a staggered head, in which two or more head chips are mounted on one support, is used. .

In addition, VH
There are two methods: recording and reproducing each signal using a head dedicated to video signals and a head dedicated to audio signals, as in the case of the 3-system, and a method of recording and reproducing each signal using a head dedicated to video signals and a head dedicated to audio signals; There are ways to record and play back video and audio. Also, as seen in professional VTRs, the video signal and audio signal are recorded and played back using the same head, and the audio signal is compressed and recorded on a part of the same track as the video signal for easy editing. There is a way to do that.

(For example, Japanese Patent Application Laid-open No. 54-125014) In multi-channel recording means, the number of heads that can be mounted is limited, so it is desirable to use one head for recording and reproducing both video and audio. Since it is easy to edit, it is common to compress the audio signal on a time axis and record it on a part of the same track as the video signal.

Problems to be Solved by the Invention When performing multi-channel recording using staggered heads, each head is very close to each other, so the timing of signal processing between each channel hardly changes. For example, in the case of three-channel recording using the helical scan method, a configuration in which single heads are arranged at equal intervals will be arranged at 60 degrees as shown in Figure 2 (a), and the timing of signal processing between each channel will be determined by the rotating drum. The difference is the amount of time it takes to rotate 60 degrees. On the other hand, Fig. 2(b)
When a staggered head is used as shown in FIG. 2, there is a slight time difference corresponding to the head gap distance d.

For this reason, in the method of compressing and recording the audio signal on a part of the same track as the video signal, when playing back the audio signal, the recording start time difference Δt between adjacent channels is longer than the time width L of the time axis compressed audio signal. If it is also large, then Figure 3 (a)
When reproduced audio signals are time-base multiplexed as shown in Figure 2, no signal overlap occurs. However, if this time difference Δt becomes smaller than the time width tA of the audio signal, the third
As shown in Figure (b), there is a period during which signals exist in two channels at a certain time, and when multiplexed, the reproduced signals overlap.

Therefore, in the configuration of Fig. 2(a), which has a large time margin, recording and reproducing audio signals could be easily achieved with a single channel circuit configuration after multiplexing, whereas in the configuration of Fig. 2(b), In some cases, it is necessary to take measures such as providing at least a delay circuit so that the signals do not overlap, increasing the compression ratio of the audio signal, or creating a three-channel circuit configuration so that the signals do not overlap.

The present invention solves the above problems, and aims to provide a recording and reproducing apparatus in which each compressed audio signal is sequentially arranged into signals without overlapping, and can process audio signals in only one channel.

Means for Solving the Problems In order to achieve the above object, the present invention uses a rotating staggered head with a plurality of head chips mounted on one support to transmit video signals and time-base compressed audio signals to a plurality of channels. In a helical scan type recording/playback device that performs recording and playback by dividing the video signal and records the time-domain compressed audio signal continuously with the video signal on an extension track of the video signal recording track, ■ time-domain compressed audio signal per track. The recording time is set to be shorter than the time difference between when one head chip in the rotating staggered head starts recording on a track and when the adjacent head chip starts recording on an adjacent track. be.

Operation The present invention has the above-described configuration, and although it uses a multi-channel recording system, the audio signal recording and reproducing circuit can be integrated into one audio signal without deteriorating the sound quality at all compared to a conventional VTR.
This can be realized with a channel circuit configuration.

EXAMPLE Hereinafter, an example of the present invention will be described with reference to the drawings. FIG. 1 is a magnetic tape format diagram of a recording/reproducing apparatus according to an embodiment of the present invention, and shows a case where the number of recording channels is three.

In the figure, 1 is a rotating staggered head, 2 is a video signal recording track, 3 is a time axis compressed audio signal recording track, and 4 is a magnetic tape. The staggered head 1 scans the magnetic tape 4 in the direction of the arrow to form a video signal track 2 and successively a time-base compressed audio signal track 3. During recording, the rotary staggered head 1 records three tracks at a time, but the gap distance d between each head chip (Fig. 2(b)
), and this time difference is equal to the recording start time difference Δt between adjacent tracks (Δt in Figure 3).
).

Therefore, if the time width (corresponding to tA in FIG. 3) of the time-axis compressed audio recording signal is set shorter than the recording start time difference Δt, the audio signal reproduced by the staggered head 1 will be adjusted as shown in FIG.
As shown in waveform 31 in a), the signals are sequential without overlapping.

Therefore, the playback system for processing audio signals recorded in channel division can have a one-channel configuration.

To define this condition using numerical values for the running system, let us assume that the scanning time of the staggered head per track is t seconds, the wrapping angle to the rotating drum per track is θ degrees, and the wrapping angle assigned to the audio signal is 61 degrees. , θ〈θ・Δt/l . . . It is necessary that (1) holds true.

Furthermore, since Δt is a function of the distance between the heald gaps, it can be seen that the recording format on the tape and the distance between the heald gaps may be adjusted to satisfy equation 1).

In this example, ■ the wrapping angle θ to the rotating drum per track is 190 degrees, the wrapping angle θ4 assigned to the audio signal is 7 degrees, and the scanning time t per track is l/60.
seconds, and the recording time difference Δt between adjacent tracks was 9×10 −′ seconds. As a result, θ·Δt/l = 10.26 degrees, which satisfies equation (1).

As described above, according to the recording and reproducing apparatus of the embodiment of the present invention, each head chip of the staggered head can be arranged so that the time width of one block of the time-axis compressed audio signal is smaller than the recording start time difference between adjacent tracks. Therefore, each compressed audio signal is sequentially arranged as a signal without overlapping, and the audio signal reproduction processing system can be integrated into one system.

Although the present embodiment has been described based on three-channel recording, it goes without saying that the same effect can be obtained using a multi-channel recording system of two or more channels using a staggered head.

Effects of the Invention As is clear from the above embodiments, according to the present invention, even in a multi-channel recording system, by adjusting the relationship between the recording format and the gap distance of the staggered head,
Since the time width of one block of the time-axis compressed audio signal is arranged to be smaller than the recording start time difference between adjacent tracks, each compressed audio signal is arranged sequentially without being superimposed, and therefore the audio signal It is possible to provide a recording and reproducing device whose scale is reduced by combining the reproducing processing systems into one system.

[Brief explanation of the drawing]

FIG. 1 is a magnetic tape format diagram of a recording/reproducing apparatus according to an embodiment of the present invention, FIG. 2 is a head arrangement diagram, and FIG. 3 is a timing chart when audio signals of each channel are multiplexed. 1... Rotating staggered head, 2... Video signal recording track, 3... Time axis compressed audio signal recording track.

Claims (2)

[Claims] (1) Using a rotating staggered head with multiple head chips mounted on one support, video signals and time-axis compressed audio signals are divided into multiple channels for recording and playback;
and a helical scan type recording and reproducing apparatus that records the time-base compressed audio signal continuously with the video signal on an extension track of a video signal recording track, wherein the recording time of the time-base compressed audio signal per track is is set to be shorter than the time from when one head chip in the staggered head starts recording on a track until the head chip adjacent to it starts recording on an adjacent track. (2) Scanning time of the rotating magnetic head per track t
seconds, the wrapping angle to the rotating drum per track is θ degrees, the wrapping angle to the rotating drum assigned to the time-base compressed audio signal is θ_A degrees, and the recording start time difference between adjacent tracks is Δt seconds, θ_A
2. The recording/reproducing apparatus according to claim 1, wherein the recording/reproducing apparatus is arranged such that <θ·Δt/t holds.