JP3731506B2 - Playback device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
  The present inventionThe present invention relates to a playback device.
[0002]
[Prior art]
Conventionally, for example, in a VHS standard magnetic recording / reproducing apparatus (VTR), a magnetic tape and a video and audio head are moved relatively at a speed of 1/3 with respect to a standard tape traveling speed and recorded in a triple mode. Long recording mode is realized. These techniques are described in, for example, Japanese Patent Application Laid-Open No. 59-124004. As means for inputting various data such as video and audio using control signals on the magnetic tape, there is a technique described in, for example, Japanese Patent Application Laid-Open No. 62-33388. As for the high-speed fast-forward / rewind technology, for example, there is a technology described in Japanese Patent Publication No. 1-217752.
[0003]
Japanese Patent Publication No. 2-63242 discloses a helical scan that records and reproduces audio and video by moving the video head over a track on the magnetic tape on which the audio head runs in order to improve the S / N ratio of the audio. A magnetic recording / reproducing apparatus of the type is described. In particular, a pair of first video heads for when the tape running speed is in the standard mode, a pair of second video heads for when the tape running speed is in the triple mode of nominal 1/3 of the standard mode, and a pair of audio. The azimuths are formed in such a manner that the heads are arranged at positions almost symmetrical with respect to the rotation axis of the rotating body for each pair, and the gap surface of each head is inclined with respect to the vertical plane in the head traveling direction for each pair. By making the angles different from each other and making the absolute value of the azimuth angle of the audio head and the azimuth angle of the first and second video heads different from each other, the audio recording and reproduction in the standard mode and the triple mode are the same. What is realized with an audio head is described.
[0004]
Further, the demand for long-time recording is not limited to three times, and it is desired to realize further long-time recording. Japanese Patent Laid-Open No. 5-266443 proposes a six-times long-time recording method. .
[0005]
[Problems to be solved by the invention]
However, it is necessary to provide a rational system that can maintain compatibility with the conventional standard mode and realize long-time recording of an arbitrary multiple.
[0006]
  The present invention maintains compatibility with existing systemsDoThis is the issue.
[0007]
  In particular,soundIt is an object to rationalize the configuration of a rotary head for voice and video, automatic tracking control, control at high speed fast forward / rewind, and the like.
[0008]
[Means for Solving the Problems]
  In order to solve the above problems, the present invention provides:A reproducing apparatus of a helical scan system, wherein a first video head for reproducing a video signal from the magnetic tape when reproducing a video signal recorded at a standard traveling speed of the magnetic tape, and the magnetic tape And a second video head that reproduces the video signal from the magnetic tape when the video signal recorded at about 1/5 of the standard speed is reproduced. The second video head reproduces a video signal when reproducing a video signal recorded at a traveling speed of the magnetic tape of about 1/3 of the standard speed.
[0009]
In this case, it is preferable that the video heads having different azimuth angles between the first and second video heads are arranged close to each other. Further, it is preferable that the first and second video heads are arranged with a delay of about 120 degrees in the rotation direction with respect to the audio head.
[0010]
Furthermore, the head width of the audio head is preferably formed to be not more than three times the track pitch in the N-times mode. In that case, tracking control during reproduction of a magnetic tape recorded in the N-times mode can be performed based on the level of an audio signal reproduced by one audio head.
[0011]
The head widths of the first and second video heads are preferably formed approximately twice the track pitch in the N-times mode.
[0012]
In addition, the second video head may be arranged with the height from the reference plane of the rotating body different from the audio head so that it travels more than four tracks behind the tracks formed in the N-times mode. preferable. In this case, the video recording signal to be supplied to the second video head is changed to the audio recording signal to be supplied to the audio head according to the number of tracks that the second video head is running behind the audio head with a delay relative to the audio head. It is preferable to stop the supply after a delay.
[0013]
On the other hand, when using the magnetic recording / reproducing apparatus described above, when the tape running speed corresponds to the triple mode of nominal 1/3 of the standard mode, an audio signal is recorded by the audio head, and the second video head is used. The video signal can be overwritten. In this case, it is preferable that the head width of the first video head is substantially equal to the track pitch width in the triple mode.
[0014]
When using the magnetic recording / reproducing apparatus described above, when the tape running speed is made to correspond to the nominal double mode of 1/2 of the standard mode, recording and reproduction are performed by the first video head and the audio head. it can.
[0015]
Also, high-speed fast-forward / rewind of magnetic tapes recorded with a tape travel speed recorded in a mode that is nominally 1 / N times that of the standard mode relative to a high-speed fast-forward / rewind speed of magnetic tapes recorded in the standard mode. It is preferable to set the return speed slower. In this case, the speed setting is preferably set in a range in which a control signal reproduced from the magnetic tape can be detected. For example, it is preferably set in a range in which the duty of the control signal can be determined.
[0016]
Further, the head width of the pair of second video heads for recording and reproducing the video signal in the 3 × mode and the N × mode can be made substantially equal to the track pitch in the 3 × mode.
[0017]
Needless to say, each of the above means can be applied to a reproduction-only helical-scanning magnetic reproducing apparatus. That is, the arrangement relationship between the video head and the audio head is the same. The video signal and the audio signal recorded in the standard mode in which the tape traveling speed is the standard speed are reproduced by the first video head and the audio head. Similarly, the tape traveling speed is approximately ½ of the standard speed. The video signal and the audio signal recorded in the 2 × mode are also reproduced by the first video head and the audio head. On the other hand, the video signal and the audio signal recorded in the triple mode in which the tape running speed is approximately 1/3 of the standard speed are reproduced by the second video head and the audio head. The N-times mode in which the tape running speed is approximately 1 / N of the standard speed (N is an integer of 4 or more) is the same as the 3-times mode. In this case, it is preferable to provide means for switching the reproduction mode.
[0018]
Further, the tape running speed is approximately 1 / N of the standard speed (N is 4 with respect to the tape running speed when the magnetic tape recorded in the standard mode in which the tape running speed is the standard speed is fast-forwarded or rewinded. It is preferable to provide speed setting means for setting the tape running speed when the magnetic tape recorded in the N-times mode, which is an integer above, is fast forward or rewind at a higher speed. In this case, the speed setting means sets the tape traveling speed when the magnetic tape is fast-forwarded or rewinded to a speed range in which a control signal reproduced from the magnetic tape can be detected. For example, the tape running speed when the magnetic tape is fast forwarded or rewinded is set to a speed range in which the duty of the control signal reproduced from the magnetic tape can be determined.
[0019]
Further, a helical scan type magnetic recording / reproducing apparatus that records or reproduces a video signal on a magnetic tape with a magnetic head mounted on a rotating body includes a pair of first video heads and a pair of second video heads. A first recording mode for recording a video signal at a standard track pitch with one video head, and a second recording mode for recording a video signal with about one third of the standard track pitch with a second video head And a third recording mode for recording a video signal at approximately 1 / N (N is an integer of 4 or more) of the standard track pitch in the second video head, and means for switching between these modes. Can be provided. Similarly, in the case of reproduction, first to third reproduction modes corresponding to these recording modes are provided and switched, and the audio head is preceded by the first and second video heads on the magnetic tape. The signal recorded in is played back.
[0020]
In the above, it is preferable to provide an N value setting means that can set the value of N to 5 or 6 and variably set the value of N. In this case, the N value setting means can arbitrarily set an integer of 4 or more as a value of N by arbitrarily selecting from a plurality of types of values. Further, the present invention can be applied to a VHS video tape recorder as a helical scan type magnetic recording / reproducing apparatus or magnetic reproducing apparatus.
[0021]
Furthermore, delay means for delaying at least one of the video recording signals supplied to the pair of first video heads that alternately form recording tracks on the magnetic recording medium, and the delay time of the delay means are substantially set for each recording track Preferably, the delay control means controls the horizontal synchronization signals recorded on the magnetic recording medium so that they are substantially aligned between adjacent recording tracks. Thereby, noise caused by the horizontal synchronization signal of the adjacent track can be reduced. In this case, a standard recording mode in which the delay times of the video recording signals supplied to the pair of first video heads by the delay control means are set substantially equal to each other and a long-time recording mode in which the delay time is variably set and recorded. And switching between these modes.
[0022]
A first recording / reproducing mode in which the magnetic recording medium travels at a first traveling speed, and a rotating body on which the magnetic head is mounted is rotated at the first rotational speed to record / reproduce; It is also possible to provide a second recording / playback mode in which the vehicle travels at a traveling speed of 2 and rotates and rotates the rotating body at the second rotational speed to switch between these modes. Here, the second traveling speed and the second rotational speed can be 1 / N (N is an integer of 2 or more), respectively, of the first traveling speed and the first rotational speed.
[0023]
Further, in addition to the first and second recording / reproducing modes, the third recording / reproducing is performed in which the magnetic recording medium travels at the third traveling speed and the rotating body rotates at the second rotational speed for recording / reproducing. Modes can be provided and these modes can be switched and used. In this case, the second travel speed is 1 / N of the first travel speed (N is an integer of 2 or more), and the third travel speed is 1 / M of the second travel speed (M is an integer of 2 or more). ) And the second rotation speed can be set to 1 / M of the first rotation speed (M is an integer of 2 or more).
[0024]
Further, a first recording mode for recording a video signal for one field on one recording track and a second recording mode for recording a video signal for M (M is an integer of 2 or more) fields on one recording track are provided. These can be switched and used.
[0025]
Also, a recording medium detecting means for detecting the type of magnetic tape or magnetic recording medium is provided, and the traveling speed of the magnetic tape or magnetic recording medium and the rotating speed of the rotating body are set or selected according to the result of the recording medium detecting means. enable. For example, when the recording medium detection means determines that the type of magnetic tape to be used is an S-VHS tape, a mode having an N value of 4 or more can be set or selected.
[0026]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.
[0027]
A first embodiment of the present invention will be described with reference to FIGS. 1 is an arrangement configuration diagram of video heads and audio heads on a rotating drum, FIG. 2 is an arrangement diagram showing steps in the mounting height direction of each head shown in FIG. 1, and FIG. 3 is a magnetic tape and video head in a standard mode. FIG. 4 is a schematic diagram showing the relative positional relationship between the magnetic tape, the video head, and the audio head in the 6 × mode. In these drawings, the same components are denoted by the same reference numerals.
[0028]
As shown in FIG. 1, a pair of video heads 2 and 3 for standard video recording / playback (standard mode) and a pair of 6x video recording / playback (6x mode) face the rotating surface of the rotary drum 1. Video heads 4 and 5 and a pair of audio heads 6 and 7 for audio recording and reproduction are arranged. The pair of video heads 2 and 3 are arranged on the rotary drum 1 with an interval of about 180 degrees, and their azimuth angles (angles formed by the gap facing surface and the vertical surface in the head rotation direction) are different from each other. It is formed by tilting in the direction. Similarly, the pair of video heads 4 and 5 and the pair of audio heads 6 and 7 are also arranged on the rotary drum 1 with an interval of about 180 degrees, and their azimuth angles are also inclined in different directions. Is formed. The video heads 2 and 5 and the video heads 3 and 4 are formed so as to have opposite azimuth angles, and are arranged close to each other. The interval between the two is set to Th (Th is normally set to 1 or 2) times the period of the horizontal synchronizing signal of the video signal normally recorded on the tape. The audio head 6 (or 7) and the video heads 3, 4 (or 2, 5) are arranged with an interval of 120 degrees.
[0029]
Note that the rotation direction of the rotary drum 1 is counterclockwise as indicated by the arrows in the figure. The azimuth angle of each head is, for example, about +6 degrees for the video heads 2 and 4, about −6 degrees for the video heads 3 and 5, about +30 degrees for the audio head 6, and about −30 degrees for the audio head 7. Has been. Thus, crosstalk between audio and video signals generated between adjacent and identical tracks is reduced using azimuth loss. Further, the head widths of the video heads 2, 3, 4, 5 and the audio heads 6, 7 and the height position of the mounting surface (the axial position of the rotating drum) are set as shown in FIG. In FIG. 2, the diagonal lines attached to the heads represent the relationship of the azimuth angle inclination direction.
[0030]
Here, FIGS. 3 and 4 show the track patterns of the audio track 9 and the video track 10 when recording on the magnetic tape 8 using the rotary head having the arrangement shown in FIGS. FIG. 3 shows a relative positional relationship among the magnetic tape 8, the video head 3, and the audio head 6 in the standard mode. The tape speed is controlled so that each track pitch is about 60 μm in accordance with the head width of the video heads 2 and 3 in the standard mode. As a result, an audio track 9 having the same width as the head width of the audio head 6 is formed on the magnetic tape 8. In the present embodiment, the head width of the audio head 6 is about 28 μm. On the audio track 9 thus recorded, a video track 10 having the same width as the head width of the video head 3 is formed by overwriting with a rotational phase delay of 120 degrees.
[0031]
By the way, since the video head 3 has a phase delay of 120 degrees with respect to the audio head 6, if the height positions of the video head 3 and the audio head 6 in the rotary drum 1 are the same, the audio head 6 preceded by the video head 3. The magnetic tape has advanced by (120 degrees / 180 degrees) of the track pitch (about 60 μm) until it reaches the same position on the magnetic tape. Therefore, considering the preceding portion 40 μm (= 60 μm × 120/180) + α, the head step between the two is set to about 58 μm as shown in FIG. 2 so that the video track 10 is overwritten on the audio track 9. Yes. Here, + α is a value for setting the audio track 9 near the center of the video track 10 as shown in FIG. As a result, the width of the overlapping portion of the audio track 9 and the video track 10 is about 28 μm. In this overlapping portion, since the azimuth polarities of both heads are different, interference between both signals does not matter. In general, an audio signal is recorded as a relatively low-frequency modulation signal up to a deep layer portion of the magnetic tape 8, and a video signal is recorded as a relatively high-frequency modulation signal on the surface layer portion of the magnetic tape 8, and is recorded first at that time. It is overwritten while erasing the modulation signal of the audio signal.
[0032]
FIG. 4 shows the relative positional relationship among the magnetic tape 8, the video head 4, and the audio head 6 in the 6 × mode. The tape speed is controlled so that each track pitch 9, 10 is formed at about 10 μm. The head width of the audio head 6 is about 28 μm as in FIG. 3, and the audio track 9 is formed on the magnetic tape 8. The video head 4 overwrites the video track 10 with a delay of 120 degrees on the rotating drum 1. Due to the rotational phase delay of 120 degrees, the magnetic tape 8 travels by (120 degrees / 180 degrees) of the track pitch (about 10 μm). In order to compensate for the deviation, it is conceivable that the head level difference between the two heads is set to about 7 μm in consideration of the preceding portion of about 7 μm (= 10 μm × 120/180). As shown in FIG. 2, it is about 49 μm. As a result, the overlap of the audio track 9 and the video track 10 is about 8 μm, as can be seen from FIG. 4, and the overlapping portion has the same azimuth polarity. However, since the azimuth angle is formed at different angles (6 degrees and 30 degrees) as described above, the azimuth loss can be sufficiently obtained, so that the interference between both signals is sufficiently removed. It can be said that the head width of the video head 4 is appropriately about 20 μm which is sufficiently wide for a track pitch of about 10 μm. As a result, it is possible to obtain a sufficient tracking performance by allowing the track to be bent.
[0033]
Next, with reference to FIGS. 5 and 6, the control at the recording end point required when recording in the 6 × mode using the audio heads 6 and 7 and the video heads 4 and 5 shown in FIG. This will be described in detail. In these drawings, the same components as those in FIGS. 1 to 4 are denoted by the same reference numerals, and description thereof is omitted. FIG. 6 is a block diagram showing the main part of the recording control means in the 6 × mode. The audio recording signal input from the input terminal 11 is amplified by the audio recording amplifier 12 and switched and supplied to the audio heads 6 and 7. The audio recording signal input thereby is alternately recorded on the adjacent audio track 9. The On the other hand, the video recording signal input from the input terminal 13 is amplified by the video recording amplifier 14 and supplied to the video heads 4 and 5 so that the input video recording signal is recorded alternately on the adjacent video track. Is done. The timing control circuit 15 generates a mute signal to be supplied to the video recording amplifier 12 and the audio recording amplifier 14.
[0034]
Here, the arrangement of horizontal synchronizing signals on the magnetic tape recorded as described above will be described. As an example of the horizontal synchronizing signal in the case of the VHS standard method, FIG. 18 shows the case of the 3 × mode, and FIG. 19 shows the case of the 6 × mode. In the VHS standard, as shown in FIG. 18, the amount of deviation (αH) of the horizontal synchronizing signal (H) between adjacent tracks is set to 0.5H during 3 × mode recording. For this reason, when one field (262.5H) is recorded on one track, the arrangement of the horizontal synchronizing signals (H) is precisely matched between the recording tracks.
[0035]
However, in the example of the 6 × mode to which this embodiment is applied, the shift amount αH is 0.25H as shown in FIG. 19, and the arrangement of the horizontal synchronizing signals (H) is disturbed between the recording tracks. When the magnetic tape thus recorded is reproduced by the head 4 having a width wider than that of the recording track shown in FIG. 19, a problem that a signal leaks from both adjacent tracks tends to occur. Basically, adjacent tracks are recorded with heads with different azimuth angles, so the adjacent components are considerably reduced due to the azimuth effect and reproduced, but the low-frequency conversion color signal and luminance that do not provide the azimuth effect. A horizontal synchronizing signal portion of a relatively low frequency component in the signal particularly has an adverse effect on leakage image quality. An example of the image monitor at this time is shown in FIG. As shown in FIG. 19, the horizontal sync signal portions leaking from both adjacent sides are shifted by 0.25 H on the left and right sides. Therefore, as shown in FIG. Deteriorate.
[0036]
FIG. 21 shows a case where the 5 × mode is set as an example of a measure for reducing such adjacent interference signals. By recording in the 5 × mode, the influence from both sides is greatly improved compared to the 6 × mode. That is, in the 6 × mode, 5 μm was detected from both adjacent tracks with respect to the main track of 10 μm (ratio: 5/10 = 0.5). Detection is 4 μm from the adjacent track (ratio: 4/12 = 0.33). In this explanation, the example of controlling the tracking so that it is detected in the same manner in the right and left adjacent tracks has been explained. It can be said that the same conditions are satisfied and it is strong against mechanical disturbance factors. Even in such a case, in the 6 × mode, since the head end is in contact with the same azimuth angle track of the adjacent track, adjacent contact interference that leads to further deterioration in image quality can be considered. From this point, the 5 × mode is more effective. Further, it goes without saying that a plurality of modes such as the 5 times or 6 times modes described in the present embodiment are used for a longer time than the conventional 3 times mode, and can be switched and used as necessary.
[0037]
Further, as a proactive solution to the disturbance due to the horizontal synchronization signal of the adjacent track, FIGS. 22 and 23 show an implementation method for matching the arrangement of the horizontal synchronization signals at the time of 6 × mode recording. FIG. 23 shows a specific circuit example of the video recording amplifier 14 shown in FIG. 6 and includes 0.25H delay circuits 71, 72, 73, SW circuit 74, recording amplifier 75, SW circuit 76, and delay control circuit 77. It is formed with. With this circuit, as shown in FIG. 22, by switching the delay time for each recording track in units of 0.25H, it is possible to ensure the alignment of the horizontal synchronizing signals of each recording track. That is, at each recording track, t₂= 0.5H, t₁= 0.25H, t₀= 0H, t_ThreeBy repeating the four modes = 0.75H, the horizontal sync signals of all the recording tracks can be aligned. Although this example has been described for the 6 × mode, the present invention is not limited to this, and the same can be done for the 5 × mode.
[0038]
By doing so, the position of the interference signal from the adjacent and adjacent tracks becomes substantially the same position as the horizontal synchronizing signal that cannot be seen on the screen monitor. In this control, the delay control circuit 77 in the video recording amplifier 14 shown in FIG. 23 supplies the four-mode output pattern to the SW circuit 74 in accordance with the signal from the timing control circuit, and from the 0.25H delay circuit 71. By selecting the optimum signal from the input / output 73 and supplying it to the heads 4 and 5 via the recording amplifier 75 and the SW circuit 76, recording with a horizontal synchronization signal arranged on the magnetic tape as shown in FIG. It can be.
[0039]
Next, a reproducing operation for reproducing the recording signal of the 6 × mode recorded as described above will be described. FIG. 7 shows the relationship between the relative positions of the magnetic tape 8, the video head 4 and the audio head 6 during reproduction in the 6 × mode. The basic relative relationship is the same as that at the time of recording shown in FIG. 5, but in order to realize optimum tracking, the phases of both are matched as shown in FIG. In other words, the audio head 6 performs tracking so that the audio track 9 to be reproduced is at the substantially center position of the head width. As a result, the audio tracks on both sides adjacent to the audio track to be reproduced are simultaneously scanned. However, since the azimuth polarity is different, there is no problem of interference, and one audio track having the same azimuth polarity is placed. The audio track is not scanned, and the problem of interference can be avoided. In order to satisfy this condition, it is preferable that the head width of the audio head 6 (or 7) is 3 times or less of the track pitch in the 6-times mode. That is, the relationship of audio head width 28 μm <track pitch 10 μm × 3 is set. As a result, the signal of the adjacent track is sufficiently attenuated due to azimuth loss, and the adjacent track can be prevented from being reproduced, and an audio signal with sufficient S / N can be reproduced. In addition, since the audio heads 6 and 7 are also used in the standard mode, it is obvious that the width as wide as possible within the above range is good for improving the S / N in the standard mode.
[0040]
Similarly, the head widths of the video heads 4 and 5 can sufficiently absorb the bending (± 5 μm) of both tracks in consideration of reproducing a magnetic tape recorded by another magnetic recording / reproducing apparatus. In addition, it is preferable to set a sufficiently wide width within a range of three times or less of the track pitch. However, if the head width is increased more than necessary, the S / N will be deteriorated. Therefore, the extent of covering the track bend, for example, 20 μm (track width 10 μm + track bend 10 μm), which is about twice the track pitch, is required. Is appropriate.
[0041]
Here, the reason why the step of the video heads 4 and 5 with respect to the audio heads 6 and 7 is set to about 49 μm will be described with reference to FIGS. 8 and 9. FIG. 8 shows the relative positional relationship between the magnetic tape 8 and the video heads 3 and 4 when the magnetic tape 8 recorded in the standard mode is reproduced at a high speed (almost three times the recording speed). FIG. 9 shows a block diagram of reproducing means for obtaining the reproducing operation of FIG. As shown in the figure, the video reproduction signals reproduced by the video heads 2, 3, 4, and 5 are amplified by the corresponding reproduction amplifiers 16 to 19, respectively. The reproduction signals from the video heads 3 and 4 are input to the level comparator 20 and the switch circuit 22, respectively. The reproduction signals of the video heads 2 and 5 are input to the level comparator 21 and the switch circuit 23, respectively. In other words, since the adjacent video heads 3 and 4 (or 2 and 5) are formed to have different azimuth angles, when performing high-speed playback, as shown in FIGS. When the output of the video head 3 decreases, it is desirable to take into account the level difference between the two video heads so that the output of the other video head 4 increases. 10 to 12, the output level of the video head 3 is indicated by an output waveform 25, and the output level of the video head 4 is indicated by 26. By doing so, it is possible to obtain a high-speed playback image with less noise by selectively selecting the one with the larger output of both the video heads 3 and 4 or by switching at equal intervals. For this purpose, it is desirable to arrange the head width centers of the video heads 3, 4 (and 2, 5) substantially the same. FIG. 10 shows output waveforms 25 and 26 of the video heads 3 and 4 at this time.
[0042]
On the other hand, considering at least the relative positional relationship at the time of recording in the 6 × mode shown in FIG. 4, the video head 4 (or 5) has four fields (corresponding to four tracks) to 6 from the audio head 6 (or 7). It is necessary to arrange the field (corresponding to 6 tracks) at a position for subsequent recording. FIG. 11 shows output waveforms 25 and 26 of the video heads 3 and 4 at the time of high-speed reproduction when arranged at a position for recording the succeeding four fields. FIG. 12 shows output waveforms 25 and 26 of the video heads 3 and 4 at the time of high-speed reproduction when arranged at a position where 6 fields follow-up recording is performed. From these figures, it can be seen that a high-speed playback image with little noise can be obtained in any case.
[0043]
The reproduction means shown in FIG. 9 is one example that realizes FIGS. That is, the level comparator 20 (or 21) compares the output signals of the reproduction amplifiers 16, 17 (or 18, 19) obtained by amplifying the outputs of the video heads 3, 4 (or 5, 2) arranged in close proximity. Then, the larger output signal is detected. Then, by selectively switching the switch circuit 22 (or 23), the larger output signal is always selected for reproduction output. The outputs of the switch circuits 22 and 23 are further selected by switching the reproduction signals of the video heads 3 and 4 or the video heads 5 and 2 by a head switching signal generated in synchronization with the rotation of the drum by the switch circuit 24. A continuous reproduction signal is output.
[0044]
Here, the level comparators 20 and 21 are not necessarily selected only by the magnitude of the output level of each reproduction amplifier, but as shown in FIGS. 10 to 12, each period (t2 to t3), (from t3) It is conceivable that t4), (t4 to t5) and (the sum of t1 to t2 and t5 to t6) are selected to be equal. This has the advantage that the video change point on the playback screen can be fixed at the same point and is easy to see. In order to realize this, it is only necessary to control the duty ratio of the outputs of the level comparators 20 and 21 to be 50%.
[0045]
Next, a reproducing operation for reproducing a recording signal recorded in the triple mode will be described. FIG. 13 shows the relationship between the relative positions of the magnetic tape 8, the video head 4, and the audio head 6 during reproduction in the triple mode. As shown in the figure, the speed of the magnetic tape is controlled so that each track pitch is about 20 μm. The head width of the audio head 6 is about 28 μm as in the above embodiment, and the audio track 9 is formed on the magnetic tape 8. The video head 4 overwrites the video track 10 with a delay of 120 degrees on the rotary drum 1. Due to the delay of 120 degrees on the rotating drum 1, the magnetic tape 8 advances by (120 degrees / 180 degrees) of the track pitch (about 20 μm), so about 13 μm (= 20 × 120 / The image head 4 scans the position of a value (about 36 μm) obtained by subtracting 180) from the head step difference of about 49 μm. As a result, the overlap of the same azimuth polarity portion of the audio track 9 and the video track 10 is about 16 μm. Further, since the head width of the video head 4 is about 20 μm, a track pitch of about 20 μm is secured, so that recording can be performed on all tracks without generating a guard band. This relationship can be reproduced while maintaining a substantially similar relationship during reproduction.
[0046]
Next, the operation at the time of recording / reproducing in the double mode will be described. FIG. 14 shows the relative positional relationship among the magnetic tape 8, the video head 3, and the audio head 6 in the double mode. In the figure, the same components as those shown in FIGS. 1 to 13 are designated by the same reference numerals and description thereof is omitted. The magnetic tape speed is controlled so that the track pitch of audio and video is about 30 μm. The head width of the audio head 6 is about 28 μm as in the above embodiment, and the audio track 9 is formed on the magnetic tape 8. Then, the video head 3 is overwritten and formed on the video track 10 with a delay of 120 degrees on the rotating drum 1. Due to the delay of 120 degrees on the rotating drum 1, the magnetic tape advances by (120 degrees / 180 degrees) of the track pitch (about 30 μm), so about 20 μm (= 30 μm × 120/180) of the preceding part. The image head 3 scans at a value (about 38 μm) obtained by subtracting from about 58 μm of both head steps. As a result, the overlap of the same azimuth polarity portions of the audio track 9 and the video track 10 is about 22 μm. Further, since the head width of the audio head 6 is about 28 μm, a guard band of about 2 μm is generated for a track pitch of about 30 μm. It goes without saying that this relationship can be reproduced while maintaining a substantially similar relationship during reproduction.
[0047]
As described above, with the configuration of the rotary head shown in FIGS. 1 and 2, the video heads 4 and 5 are used in the 3 × mode and the 6 × mode, and the video head 2 is used in the standard mode and the 2 × mode. Recording or reproduction can be realized by using 3 respectively.
[0048]
Next, control means for controlling the relative speed and phase between the magnetic tape and the audio and video heads in the magnetic recording / reproducing apparatus having the recording or reproducing mode at various tape speeds according to the above-described embodiment will be described. Here, the reproduction tracking control in the 6 × mode shown in FIG. 7 will be described as an example in detail.
[0049]
FIG. 15 shows a book configuration diagram of the reproduction tracking control apparatus. In the figure, the same components as those in FIGS. The magnetic tape 8 travels in contact with the rotating surface of the rotating drum 1, and the rotating drum 1 is driven to rotate by a drum motor 27. In addition, the magnetic tape 8 is sandwiched between a capstan 28 and a pinch roller 29, and the capstan 28 is rotationally driven by a capstan motor 30 so that the traveling speed of the magnetic tape 8 can be controlled. The audio signal reproduced by the audio heads 6 and 7 provided on the rotary drum 1 is switched by the head switch circuit 31, and the audio signal of one of the audio heads 6 and 7 is input to the preamplifier 32. Yes. The audio signal amplified by the preamplifier 32 is input to the audio signal processing circuit 33 and the envelope detection circuit 34. The audio signal processing circuit 33 demodulates the modulated audio signal and performs necessary audio signal processing to restore and output the reproduced audio signal. The envelope detection circuit 34 detects the amplitude component of the audio signal and outputs it to the rotating drum / capstan control means 45.
[0050]
The rotating drum / capstan control means 45 includes a drum servo control circuit 35, a head switch signal (HSW) generation circuit 36, a capstan servo control circuit 39, a reference signal generator 40, a delay circuit 41, and a tracking control circuit 42. Is formed. The drum servo control circuit 35 generates a signal for controlling the speed and phase of the drum motor 27 from the DFG signal and DPG signal generated by the drum motor 27, and controls the drum motor 27 via the driver circuit 37. The head switch signal generation circuit 36 generates the switching timing of the audio heads 6 and 7 based on the DPG signal or the DFG signal that is standardized by the DPG signal, and controls the head switch circuit 31 based on this. The capstan servo control circuit 39 runs the tape on the basis of the recording / reproducing mode set by the mode switching means 86 and the control signal and CFG signal reproduced by the control head 43 arranged in contact with the magnetic tape 8. A signal for controlling the speed and phase is generated, and the capstan motor 30 is controlled via the driver circuit 38. Thus, the relative position between the magnetic tape 8 and the sound heads 6 and 7 is controlled. In the description of FIG. 15, all the electrical processing portions are expressed as circuits. However, for example, the rotating drum / capstan control means 45 can also be configured by software using an appropriate microcomputer.
[0051]
Next, the operation of the embodiment of FIG. 15 will be described with reference to FIG. First, the signal of the audio track 9 recorded on the magnetic tape 8 by helical scanning is reproduced by the two audio heads 6 and 7 arranged on the rotary drum 1 and alternately selected by the head switch circuit 31. Read out. Although not shown, the video signal is also reproduced by the video heads 2 and 3 or the video heads 4 and 5 arranged on the rotary drum 1, and a continuous reproduction signal is obtained via the head switch circuit and demodulated. Processed and output video signal.
[0052]
On the other hand, the drum servo control circuit 35 generates a speed control signal so as to keep the period of the DFG signal constant, and compares the phase of the DPG signal and the output signal of the reference signal generator 40 to achieve phase synchronization between the two. Thus, the rotational phase of the drum motor 27 is controlled. The capstan servo control circuit 39 generates a speed control signal so as to keep the cycle of the CFG signal constant, a control signal obtained from the magnetic tape 8 via the control head 43 and the reproduction amplifier 44, and a reference signal. A phase comparison is made with a signal obtained by delaying the output signal of the generator 40 via the delay circuit 41, and the rotation of the capstan motor 30 is controlled so as to synchronize the phase of both. Further, the mode switching means 86 controls the capstan servo control circuit 39 to control various tape running speed modes.
[0053]
Here, tracking control using the capstan motor 30 is performed as follows. First, the envelope detection circuit 34 detects the amplitude component of the audio signal read from the magnetic tape 8. Thereby, the audio signal output from the envelope detection circuit 34 is shown in, for example, FIG. 16 depending on the relative relationship between the audio track 9 formed on the magnetic tape 8 and the trace phase (traveling position) of the audio heads 6 and 7. It becomes like this. That is, while the width of the audio track 9 is about 10 μm, and the head width of the audio heads 6 and 7 is about 28 μm, the output of the adjacent tracks is hardly reproduced due to the azimuth effect, but the adjacent tracks are the same. Recycled because it is azimuth polar. Therefore, when the audio head 6 or 7 traces the center of the azimuth track having the opposite polarity, a reproduction signal having a level corresponding to a width of 9 μm is detected from each of the azimuth tracks having the same polarity on both sides (the wavy line in FIG. 16). The positional relationship of the audio head 6 shown in FIG. However, since the signals reproduced from each track have no correlation, there are signal components that cancel each other out, and the signal level is lower than that reproduced from the same track. As shown in the lower part of FIG. The relative output level changes with the change of the relative phase. Using these results, the optimum tracking phase is set using the delay circuit 41. For example, as shown in FIG. 16, the optimum value may be set to the center value by detecting a place where the output levels on both sides of the relative output level are equal.
[0054]
With reference to FIGS. 24 and 25, another embodiment according to the present invention will be described. This embodiment is an example of a method of recording for a long time by reducing not only the magnetic tape feeding speed described above but also the rotating head rotational speed. FIG. 24 is a diagram showing the relative positions of the recording track on the magnetic tape and the recording head during 6 × mode recording according to the present invention. FIG. 25 shows specific circuit means of the drum servo processing circuit 35 of FIG. 15 in order to explain in detail the specific circuit means for realizing FIG. As shown in FIG. 25, the drum servo processing circuit 35 includes a double circuit 78, SW circuits 79 and 80, a speed detection circuit 81, a phase detection circuit 82, an addition circuit 83, a 6-times mode instruction input terminal 84, 1 / A divide-by-2 circuit 85 is included.
[0055]
FIG. 24 is the same as the 3 × mode recording pattern shown in FIG. 13. Just the recorded signal is changing. That is, in the 3 × mode shown in FIG. 13, the video signal for one field is recorded on one track, whereas in this example, the video signal for two fields is recorded on one track. Record the information. This method is realized by setting the traveling speed of the magnetic tape to the 6 × mode and simultaneously reducing the rotational speed of the rotary head to ½. As a result, it is possible to create a recording track pattern that is not affected by the interference signal from the adjacent and adjacent tracks at the time of reproduction. Of course, since the relative speed of the magnetic tape and the rotating head is reduced, attention must be paid to the output reduction of the high-frequency component of the frequency-modulated video signal, but the recent high-resolution mode (corresponding to the S-VHS mode in the VHS system) is used. Sufficient performance is being achieved to perform recording and reproduction in the normal mode using the realized magnetic tape and head. For this reason, for example, it is desirable to limit the present recording mode to the settable mode only when an S-VHS cassette tape is inserted.
[0056]
Next, the specific implementation means of FIG. 24 will be described in detail with reference to FIG. 15 and FIG. Since the control of the 6 × mode of the magnetic tape has already been described with reference to FIG. 15, specific circuit means for controlling the speed of the rotary head to 1/2 will be described with reference to FIG. This figure shows a circuit configuration provided in the drum servo processing circuit 35 for controlling the rotation of the rotary head. In this long time mode (six times) with respect to the normal mode, the SW circuits 79 and 80 operate in response to an instruction from the input terminal 84, and the DFG signal generated according to the rotational speed of the drum having the rotary head is The drum motor is controlled by the double frequency 78 through the double circuit 78 and the speed detection circuit 81 and the addition circuit 83 through the SW circuit 79. Therefore, as a result, the rotary head is controlled at a speed ½ that of the normal mode. The phase detection circuit 82 divides the signal from the reference signal generator 40 into ½ by the ½ divider circuit 85 and supplies the divided signal to the drum rotation phase signal DPG through the SW circuit 80. By detecting the input and phase, the 1/2 speed control can be similarly performed for the phase control.
[0057]
Although not shown, the signal input to the input terminal 84 detects what kind of magnetic tape is currently inserted by the system controller as described above. For example, only in the case of an S-VHS tape The long-time recording mode may be set. In this example, it is described that two fields are recorded in one track. However, it can be easily understood that a system for recording three or more fields in one track can be configured.
[0058]
Next, a control operation for high-speed fast-forward / rewind of the magnetic tape 8 according to the present invention will be described with reference to FIG. FIG. 1 is a block diagram showing a high speed fast forward / rewind control apparatus according to an embodiment. In the figure, the same components as those in FIGS. As illustrated, the magnetic tape 8 is wound around two reels 46 and 47. The reels 46 and 47 are engaged with reel stands 48 and 49, respectively, and the reel stands 48 and 49 are rotationally driven by a motor 54 via a driving force transmission means 55. FG (Frequency Generator) pulse generators 50 and 51 detect the rotational speeds of the reel bases 48 and 49, respectively, and output pulses having a frequency proportional to the rotational speeds. The brakes 52 and 53 provided on the reel bases 48 and 49 are driven by a brake driving means 66. The rotational speed of the motor 54 is detected by the FG pulse generator 56. Although not shown, the rotating drum and the capstan are provided in contact with the magnetic tape 8 transferred between the reels 46 and 47.
[0059]
Here, the detailed configuration of the high-speed fast-forward / rewind control device will be described together with the operation by taking the case where the magnetic tape 8 is run at a high speed of Vn as an example. The motor 54 is driven to rotate by an output signal from the motor driver 64. The driving force of the motor 54 is transmitted via the driving force transmitting means 55 to the reel base 49 when fast-forwarding and to the reel base 48 when rewinding. As a result, the magnetic tape 8 is wound on the reel 47 when fast-forwarding and wound on the reel 46 when rewinding. At this time, the speed of the reel base 48 is detected by the FG pulse oscillator 50, the speed of the reel base 49 is detected by the FG pulse oscillator 51, and the speed of the motor 54 is detected by the FG pulse oscillator 56. The detected pulse signals having frequencies indicating the rotation speeds of the reel bases 48 and 49 and the motor 54 are input to the winding diameter detecting means 57 and the speed detecting means 58.
[0060]
In the winding diameter detection means 57, for example, the winding diameter values (radius) Rs and Rt of the reels 46 and 47 are obtained by the following mathematical formula 1.
[0061]
[Expression 1]
Rs = √ {S / (π · (1+ (Tt / Ts)²))}
Rt = √ {S / (π · (1+ (Ts / Tt)²))}
Here, S indicates the total winding area of the tape including the reel hub when the magnetic tape is viewed from above, and Ts and Tt indicate the periods of pulses output from the FG pulse oscillators 50 and 51, respectively.
[0062]
On the other hand, the speed detection means 58 obtains the running speed V of the magnetic tape by the following formula 2, for example.
[0063]
[Expression 2]
V = 2 · π · Rt / Tt
The winding diameter values (radius) Rs and Rt detected by the winding diameter detection means 57 are input to the speed detection means 58 and the deceleration setting means 59. The speed data V detected by the speed detection means 58 is input to the speed error detection means 61 and the stop determination means 65. In the deceleration setting means 59, a deceleration a in which tape slack does not occur during deceleration is set by the winding diameter value (radius) Rs or Rt input from the winding diameter detection means 57. Here, in order to perform the decelerating running without tape slack, it is necessary to set the deceleration a of the tape take-up reel to be controlled to be equal to or less than the deceleration due to the load torque of the tape supply reel to be controlled. . That is, deceleration a [mm / s²] Is set by Equation 3 below. In Equation 3, T, R, and I are the load torque [gr / mm], winding value (radius) [mm], and moment of inertia [gr / mm] of the tape supply side reel, respectively.²]. The load torque T and the moment of inertia I need to be obtained in advance by measurement or the like. Here, the tape supply side is the reel 46 side when fast-forwarding, and the reel 47 side when rewinding.
[0064]
[Equation 3]
a ≦ T ・ R / I
The deceleration a set by the deceleration setting means 59 is input to the target speed switching means 60. In the target speed switching means 60, the target speed Vn is set by a speed switching signal input via the input terminal 70. The set target speed Vn is input to the speed error detecting means 61. The speed error detecting means 61 calculates an error component between the speed data V detected by the speed detecting means 58 and the target speed Vn set by the target speed switching means 60. The speed error component calculated by the speed error detecting means 61 is fed back to the motor 54 via the PWM generator 62, the integrator 63, and the motor driver 64. Thereby, the tape running speed V is made to follow the target speed Vn.
[0065]
At the time of such high-speed fast-forward / rewind, there is a control for detecting a cueing signal recorded on the control signal by duty ratio modulation from the magnetic tape 8 and stopping the magnetic tape 8 based on this. In the figure, the control signal on the magnetic tape 8 is detected by the data detection means 67 via the control head 43. The output of the data detection means 67 is input to the target speed switching means 60 and the stop determination means 65 via the adder 68. The target speed switching means 60 starts subtraction of the target speed Vn by inputting a stop signal. Here, the subtraction amount per unit time of the target speed Vn is proportional to the deceleration a input from the deceleration setting means 59. As a result, the target speed Vn changes with an inclination corresponding to the deceleration a. Accordingly, the traveling speed V follows the target speed Vn and is decelerated at the deceleration a. On the other hand, after the stop signal is input, the stop determination means 65 outputs a brake permission signal when it is detected that the speed data V input from the speed detection means 58 is equal to or lower than the allowable speed VL. The brake permission signal output from the stop determination unit 65 is input to the brake drive unit 66. The brake drive means 66 drives the brakes 52 and 53 by the brake permission signal from the stop determination means 65 to stop the tape running.
[0066]
Therefore, if the target speed Vn output from the target speed switching means 60 is a speed VH that exceeds the allowable speed VL, after the stop signal is input, the speed is decelerated from the speed VH to the speed VL, and then a brake permission signal is output from the stop determination means 65. Output and stop running. Here, since the deceleration also changes as the winding diameter value of the supply-side reel changes, the brake timing differs for each winding diameter value.
[0067]
If the target speed Vn is a speed equal to or lower than the allowable speed VL, the stop operation is stopped simultaneously with the input of the stop signal, and a brake permission signal is output from the stop determination means 65 to stop traveling.
[0068]
Further, by changing the output of the target speed switching means 60 according to which recording mode the magnetic tape 8 is recorded in from the standard mode to the 6 × mode, the usability for each application can be improved. In other words, in the case of designating the mode in which the magnetic tape 8 is simply rewound to the head portion, the highest rewound speed may be set regardless of the recording mode. However, at the time of fast forward / rewind in the mode in which the cue signal superimposed on the control signal is detected and stopped, the frequency of the control signal reproduced from the magnetic tape 8 at the same magnetic tape 8 speed is recorded in the standard mode. The magnetic tape recorded in the 6 × mode is detected at a frequency 6 times higher than the recorded magnetic tape. In this case, it is conceivable that the frequency of the reproduction control signal becomes too high to detect the reproduction control signal. The reproduction control signal is used for information for managing the tape position based on this number. If the reproduction control signal cannot be detected, the system is inconvenient. Further, even if the number of reproduction control signals can be detected, if the cue signal superimposed on the reproduction control signal cannot be detected, the system will be inconvenient.
[0069]
Therefore, means for limiting the fast forward / rewind speed in the 6 × mode is provided. That is, the target speed switching means 60 sets the high speed fast forward / rewind speed by supplying a speed switching signal from the input terminal 70. As a result, in the newly recorded tape recorded in the 6 × mode, the cue signal superimposed on the control signal on the magnetic tape is detected and stopped at the desired position even in the high speed fast forward / rewind mode. Control can be realized.
[0070]
Further, the recording mode discrimination at the time of reproduction can be made by comparing the control signal frequency that is normally reproduced and the magnetic tape speed. The input terminal 69 is an input signal when the operator manually performs a stop operation. Further, the motor 54 may be the same as the capstan motor 30 shown in FIG.
[0071]
As described above, according to the magnetic recording / reproducing apparatus according to the embodiment of the present invention, the following effects can be obtained.
(1) A video signal and an audio signal can be recorded and reproduced in the N mode (for example, 5 times or 6 times) mode for a long time together with the standard mode with the same audio head.
(2) When realizing recording / reproducing in 3 × mode, a video head for N × (for example, 5 × or 6 ×) mode can be shared.
(3) When realizing the recording / reproducing in the double mode, the standard mode video head can be shared.
(4) By using an audio head output as an optimal tracking method at the time of reproduction in N times (for example, 5 times or 6 times) mode, both audio and video can be optimally tracked.
(5) When recording in N times (for example, 5 times or 6 times) mode is stopped, the audio signal recording is first stopped for a period of at least 4 fields, thereby reliably overwriting the video track on the audio track. be able to.
(7) By setting the high-speed fast-forward / rewind speed in N times (for example, 5 times or 6 times) mode to a low speed compared to the tape speed in the standard mode, the cue signal from the magnetic tape is surely obtained. Can be detected.
(8) It is possible to align the horizontal sync signals between adjacent tracks of the recording pattern in the N times (for example, 5 times or 6 times) mode, thereby making it difficult to see the influence of adjacent crosstalk on the screen. .
[0072]
【The invention's effect】
  According to the present invention, the compatibility with the existing system is maintained, and the triple mode is exceeded.
Long timeAgainRealize life.
[Brief description of the drawings]
FIG. 1 is a configuration diagram of an embodiment of a rotary head of a magnetic recording / reproducing apparatus according to the present invention.
FIG. 2 is a diagram showing the positional relationship of each head of the rotary head shown in FIG.
FIG. 3 is a diagram showing a relative positional relationship between a magnetic tape and each head during standard mode recording.
FIG. 4 is a diagram showing a relative positional relationship between a magnetic tape and each head at the time of recording / reproducing in a 6 × mode to which the present invention is applied.
FIG. 5 is a relative positional relationship diagram illustrating recording stop timings of the video head and the audio head when recording is stopped in the 6 × mode to which the present invention is applied.
FIG. 6 is a control block diagram for controlling the recording stop timing of the video head and the audio head when recording is stopped in the 6 × mode.
FIG. 7 is a diagram showing a tracking phase relationship between a magnetic tape and each head during 6 × mode reproduction to which the present invention is applied.
FIG. 8 is a diagram showing a relative positional relationship between a magnetic tape and each head during search reproduction in a standard mode to which the present invention is applied.
FIG. 9 is a control block diagram of search reproduction in standard mode.
FIG. 10 is a waveform diagram showing output levels of the video head 3 and the video head 4 during standard mode search reproduction;
FIG. 11 is a waveform diagram showing output levels of the video head 3 and the video head 4 during search reproduction in the standard mode.
12 is a waveform diagram showing output levels of the video head 3 and the video head 4 at the time of search reproduction in the standard mode. FIG.
FIG. 13 is a diagram showing a recording pattern on a 3 × mode magnetic tape using a rotary head according to the present invention;
FIG. 14 is a diagram showing a recording pattern on a double-mode magnetic tape using a rotary head according to the present invention.
FIG. 15 is a control block diagram of an embodiment of optimal tracking control during 6 × mode reproduction according to the present invention.
16 is a diagram for explaining the operation of the control block diagram of FIG. 15;
FIG. 17 is a block diagram of an embodiment of high-speed fast forward / rewind control means in the 6 × mode according to the present invention.
18 is a recording pattern diagram on the magnetic tape showing the recording pattern of FIG. 13 in an enlarged manner.
FIG. 19 is an enlarged pattern diagram showing the tracking phase relationship between the magnetic tape of FIG. 7 and each head.
20 is a diagram showing a display example of a video signal reproduced by the recording pattern of FIG.
FIG. 21 is a detailed relative positional relationship diagram showing a tracking phase relationship between a tape and a head when a 5 × mode recording pattern to which the present invention is applied is reproduced.
22 is a recording pattern diagram obtained by improving the recording pattern of FIG.
23 is a circuit diagram showing a detailed circuit example for realizing the recording pattern of FIG. 22. FIG.
FIG. 24 is a relative positional relationship diagram showing a tracking phase relationship between a tape and a head during 6 × mode reproduction according to another embodiment of the present invention.
25 is a circuit diagram showing an example of circuit means for realizing the tracking phase relationship of FIG. 24. FIG.
[Explanation of symbols]
1 Rotating drum
2, 3 (for standard mode) Video head
4, 5 (for 6x mode) video head
6, 7 Audio head
8 Magnetic tape
9 Audio track
10 Video track
15 Timing control circuit
27 Drum motor
28 Capstan
30 Capstan motor
34 Envelope detection circuit
35 Drum servo control circuit
39 Capstan servo control circuit
40 Reference signal generator
41 Delay circuit
42 Tracking control circuit
43 Control head
48, 49 reel stand
50, 51, 56 FG pulse generator
54 Motor
55 Driving force transmission means
57 Winding diameter detection means
58 Speed detection means
59 Deceleration setting means
60 Target speed switching means
61 Speed error detection means
65 Stop determination means
66 Brake drive means
67 Data detection means
71-73 0.25H delay circuit
74, 76 SW circuit
75 recording amplifier
77 Delay control circuit
78 Double circuit
79, 80 SW circuit
81 Speed detection circuit
82 Phase detection circuit
83 Adder circuit
84 Input terminal
86 Mode switching circuit

Claims (11)

A helical scan playback device,
A first video head for reproducing a video signal from the magnetic tape when reproducing a video signal recorded at a standard traveling speed of the magnetic tape;
A second video head for reproducing a video signal from the magnetic tape when reproducing a video signal recorded at a traveling speed of the magnetic tape of about 1/5 of the standard speed;
The second video head plays back a video signal when playing back a video signal recorded at a traveling speed of the magnetic tape of about 1/3 of the standard speed.   The head width of the second video head is the track pitch of the video signal recorded on the magnetic tape when a video signal recorded at a traveling speed of the magnetic tape of about 1/3 of the standard speed is reproduced. The playback device according to claim 1, wherein the playback devices are equal. A helical scan playback device,
A first video head and a second video head for reproducing a video signal from a magnetic tape;
The first video head plays back a video signal recorded at a standard track pitch, and the second video head plays a video signal recorded at about 1/3 and about 1/5 of the standard track pitch. And a control means for controlling the first video head and the second video head so as to perform playback.   4. The reproducing apparatus according to claim 3, wherein a head width of the second video head is substantially equal to about 1/3 of the standard track pitch. A helical scan playback device,
A first video head and a second video head for reproducing a video signal from a magnetic tape;
An audio head for reproducing audio signals from magnetic tape;
A first reproduction mode for reproducing a video signal and an audio signal recorded at a standard track pitch by the first video head and the audio head; and the standard track pitch by the second video head and the audio head. Switching means for switching between a video signal recorded at about 1/5 and a second reproduction mode for reproducing an audio signal;
A third reproduction mode for reproducing a video signal and an audio signal recorded at about 1/3 of the standard track pitch by the second video head and the audio head; A playback device that switches between a playback mode, the second playback mode, and the third playback mode.   6. A reproducing apparatus according to claim 1, wherein the reproducing apparatus is a VHS standard video tape player.   The first video head and the second video head each include a pair of heads, and the azimuth angles of the pair of heads are formed to be inclined in different directions. Item 7. The playback device according to any one of Items 6 to 7.   8. The reproducing apparatus according to claim 1, wherein video heads having different azimuth angles of the first video head and the second video head are arranged close to each other.   9. The reproduction according to claim 1, wherein the first video head and the second video head are arranged with a delay of approximately 120 degrees in the rotation direction with respect to the audio head. apparatus.   6. The reproducing apparatus according to claim 5, wherein the audio head reproduces an audio signal recorded on the magnetic tape prior to the first video head and the second video head.   The recording medium detection means for detecting the type of the magnetic tape is provided, and the traveling speed of the magnetic tape can be set or selected according to the result of the recording medium detection means. The playback apparatus according to any one of 10.

Images