JP2978024B2 - Magnetic recording / reproducing device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic recording / reproducing apparatus having a rotating head for video, audio, and erasing, and more particularly to a home Hi-Fi VTR (Vidoe Tape Recorder).
The present invention relates to a magnetic recording / reproducing apparatus which can be used at the time of insert recording such as er).

[0002]

2. Description of the Related Art FIG. 4 shows a conventional insert recording circuit.
In the figure, 21 is a rotary erase head (referred to as a FE (flying erase) head), 22 is a rotary audio head, 23 is a standard mode video head, 24 is a long time mode video head, 25 is an audio recording amplifier, and 26 is an audio recording amplifier. A standard mode recording amplifier, 27 is a long-time mode recording amplifier, 28 is a mode discrimination circuit, 29 is a counter circuit, 30 is a recording control circuit,
31 a servo circuit, 32 to 35 switch, a ₂ is reproduced control signal (reproduced CTL signal), b ₂ is the PG pulse signal.

First, after setting a recording start track on a tape, an insert recording command is input to a recording control circuit 30. The recording control circuit 30 controls a counter 29 to count the reproduction CTL signal a ₂ by a predetermined amount. The servo circuit 31 is controlled to rewind and temporarily stop. Next, the editor issues a temporary stop release command (not shown) according to the video to be inserted. In the insert recording mode, no erasing current is supplied to the full-width erasing head (not shown). Between several frames until the recording start point and the phase adjustment period, the mode from the playback CTL signal a ₂ discriminating circuit 2
In step 8, the recording mode in the insert section is determined, and the servo circuit 31 controls the capstan and head phases correctly while synchronizing with the external video signal. On the other hand, the head switch SW2 switches the recording video head to the standard video head 23 or the long-time video head 24 based on the mode determination signal sent from the mode determination circuit 28.

FIGS. 5 (a) to 5 (j) are timing charts of recording start / end during insert recording, and FIGS. 6 and 7 are diagrams showing the arrangement of the heads on the rotating drum, the widths of the heads, and the steps. . In the figure, 21a is a first FE head, 21b is a second FE head, 22a is a rotary audio head (R), 22
b is a rotary audio head (L); 23a is a standard mode video head (R); 23b is a standard mode video head (L); 24a is a long mode video head (R);
Reference numeral 4b denotes a long-time mode video head (L). "R" and "L" indicate the respective channels of the rotary head pair.

The PG pulse signal b ₂ generates positive and negative pulses alternately every half-circle of the drum. Since the phase difference between the PG pulse signals b ₂ and each head are each constant, the timing of each head Knowing PG pulse signal b ₂ is in contact with the tape is found. If the pulse of the CTL signal corresponding to the insert recording start track is set to count "0", the counter 29 indicates the count "-1" during the phase adjustment period, and the first positive PG pulse is generated. The recording control circuit 30 controls the PG to start recording.
By shifting a predetermined time (phase) from the pulse signal b ₂ ,
Recording is started by turning the switches W3, SW4, and SW5 from off to on (FIGS. 5 (h), (i), and (j)). When the recording is stopped, the recording control circuit 30 detects the positive PG pulse immediately after the input of the stop command, as in the case of starting the recording, as shown in FIGS. 5 (h), (i), and (j). SW3 from the PG pulse signals b ₂ of the positive shifting a predetermined time (phase),
The switches of SW4 and SW5 are turned from on to off, and the subsequent recording on the track is stopped.

Further, as a known document describing the prior art according to the present invention, there is, for example, "Video Tape Recorder" in Japanese Utility Model Laid-Open Publication No. 63-81303. This publication has a splicing or insert recording function, and is provided with an amplification circuit and a switching circuit that can change the recording current of an audio head for deep recording, so that the recording current is higher than that during normal recording. Is made larger.

[0007]

As described above, in the conventional insert recording circuit, the width of the FE head is made in accordance with the standard mode (FIG. 7). As shown in FIG. 8), correct erasing is performed for each track, but when the same FE head is used in the long-time mode, a plurality of tracks are erased at once as shown in FIG. 8B. However, a blank track portion is formed at the end of the insert. For this reason, conventionally, when the stop button is pressed (or the insertion end point is reached) during insert recording, recording is continued for the tracks that have already been erased at the time when the stop button is pressed (reached), and then recording is stopped. Was working like that. However, according to this method, a gap in the insert section and a gap in time at the end point occur because recording is further performed for a plurality of tracks from the original end point, and although it is a short section and a short time, it is very troublesome. It was something.

In the above-mentioned publication, there is a method in which insert recording is performed by increasing the recording current of a rotary audio head.
The rotating audio head has a smaller track width than the standard video head, and has no effect in the standard mode. Also,
Conventionally, insert recording of only one field cannot be performed, so that editing for special effects has been limited.

The present invention has been made in view of such circumstances, and in order to eliminate a short but very noticeable time lag at the end point of insert recording, a rotary erasing head in a standard mode is used as an erasing head. In the long-time mode, the insert recording is performed for each track using the rotary audio head in the long time mode, and the insert recording is performed for every other track (field), so that only one of the fields is inserted. It is an object of the present invention to provide a magnetic recording / reproducing device.

[0010]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a rotary head for long-time mode video, standard mode video, audio, and erasure, and a recording mode of a recorded tape. in the magnetic recording and reproducing apparatus capable inserts record and a determination to the mode determination circuit, when the signal and insert a recording command from the mode discrimination circuit is input, a control circuit for outputting a control signal, long
If there is an insert command in the mode,
The information of the recorded track is recorded by the rotary head for audio by the control signal.
Information and insert it with the rotating head for long-time mode video.
Record insert information and insert command in standard mode.
In the case, the information of the recorded track is erased by the rotary head for erasing.
To record insert information with the rotating head for standard mode.
Switching selection is performed as described above.

[0011]

The FE head and the rotary audio head are switched according to the mode. Since the track width of the rotating audio head is generally made to match the track width of the long-time mode (which may be slightly wider than this), it is much faster than when the FE head is used in the long-time mode. Since it is close to the track width and accurate erasure can be performed for each track, the extremely unpleasant time lag at the end point of the insert recording is eliminated in both the standard mode and the long-time mode. Becomes possible.

[0012]

Embodiments will be described below with reference to the drawings. FIG. 1 is a block diagram for explaining one embodiment of a magnetic recording / reproducing apparatus according to the present invention. In the drawing, reference numeral 1 denotes a rotary erasing head (FE (flying erase) head); Mode video head, 4 is a long-time mode video head, 5 is a gain adjustment circuit, 6 is an audio recording amplifier, 7 is a standard mode recording amplifier, 8 is a long mode recording amplifier, 9 is a mode discrimination circuit, 10 recording control circuit, counter circuit, 11 is 12 the servo circuit, the aND circuit 13, 14 to 18 switch, a ₁ is reproduced control signal (reproduced CTL signal), b ₁ is the PG pulse signal.

[0013] First, after setting the recording start track on the tape, the insert recording command is input to the recording control circuit 11, the recording control circuit 11 a predetermined amount to wind the tape while counting the reproduced CTL signal a ₁ by the counter 10 Let me go back
The servo circuit 12 is controlled so as to temporarily stop. Next, the editor issues a command to start insert recording according to the video to be inserted. In the insert recording mode, no erase current is supplied to the full-width erase head (not shown). Between several frames until the recording start point and the phase adjustment period, to determine the recording mode of the insert section in the mode determination circuit 9 from the reproduction CTL signal a _1, and an external video signal capstan and the head of the phase servo circuit 12 Control correctly while synchronizing. On the other hand, the head changeover switch S
W2 switches the recording video head between the standard video head 3 and the long-time video head 4 based on the mode determination signal sent from the mode determination circuit 9.

The mode discriminating circuit 9 also sends a mode discriminating signal to an AND circuit (control circuit) 13. In the AND circuit 13, a mode discrimination signal sent from the mode discrimination circuit 9 and
When an insert command is input and “long time mode & insert command is present”, an H control signal is output; otherwise, an L control signal is output. The circuit which performs such an operation does not need to be an AND circuit.
The control signal output from the AND circuit 13 is the ON / OFF switch SW1 of the FE head 1 and the gain adjustment circuit 5
Sent to When the control signal is H, the FE head 1 is turned on /
The off switch SW1 turns the switch off. On the other hand, when the control signal is H, the gain adjustment circuit 5 increases the gain of the audio recording amplifier 6 more than usual, thereby improving the recording capability.

FIGS. 2A to 2J are timing charts of recording start / end at the time of insert recording. The arrangement of the heads on the rotating drum, the widths of the heads, and the steps are described above with reference to FIGS.
This will be described with reference to FIG. Note that 1a in FIG.
E head, 1b is a second FE head, 2a is a rotary audio head (R), 2b is a rotary audio head (L), 3a is a standard mode video head (R), 3b is a standard mode video head (L). 4a is a long mode video head (R), 4a
b is a long mode video head (L).

[0016] For each drum half the phase difference between the PG pulse signals b ₁ to generate positive and negative pulses alternately to each head are each constant, each head Knowing PG pulse signal b ₁ is in contact with the tape You know when to do it. When a pulse of the reproduced CTL signal a ₁ corresponding to the insert recording start track a count "0", after the counter 10 in the phase adjustment period showed counts "-1", if the first positive PG pulse is generated The recording control circuit 11 causes the PG pulse signal b ₁ to start recording from that track.
SW3, SW4, S
Recording is started by turning each switch of W5 from off to on (FIGS. 2 (h), (i), (j)). At this time, as described above, SW1 has already been turned off in the long-time mode (FIG. 2G), and the FE head does not function.

When the recording is stopped, the recording control circuit 11 detects the PG pulse immediately after the input of the stop command as in the case of starting the recording, as shown in FIGS. 2 (h), (i) and (j). , The P
S from G pulse signal b ₁ by shifting a predetermined time (phase)
The switches W3, SW4, and SW5 are turned on-off, and the subsequent recording on the track is stopped. In the case of terminating the insert recording in units of frames, the recording control circuit 11 detects a positive PG pulse immediately after the stop command is input, PG pulse signal b ₁ from the predetermined time of the positive (phase) If the switches SW3, SW4, and SW5 are set to be turned off by shifting, the insertion for each frame is also possible. Therefore, according to the present invention, in the long time mode, the insert information is recorded while erasing the information of the recorded track by the rotary audio head as shown in FIG. 3 (b), and in the standard mode, as shown in FIG. 3 (a). The FE head 1 functions, and the audio and video signals are recorded after erasing the preceding recorded track.

On the other hand, if the recording control circuit 11 is set to record only one channel (R or L), insert recording of only one field can be performed. in this case,
2, the positive and negative PG pulse signals b ₁ shown in FIG. 2 (b) preceding the respective heads, to determine the channel then come head, if PG pulse signal b ₁ is positive SW3, S
W4, SW5 sequentially on, may be set recording control circuit 11 so as PG pulse signal b ₁ is if negative SW3, SW4, SW5 (also possible of course the reverse) successively off the to.

[0019]

As is apparent from the above description, the present invention has the following effects. That is, even in the long time mode, accurate erase trace for each track according to the track width can be performed, and the time lag at the end point of the insert recording is eliminated. In the conventional example, an FE head that erases in units of fields is used. However, when an FE head that erases in units of frames is used, the effect is more enhanced. Also, insert recording of only one of the R channel and the L channel can be performed.

[Brief description of the drawings]

FIG. 1 is a configuration diagram for explaining an embodiment of a magnetic recording / reproducing apparatus according to the present invention.

FIG. 2 is a timing chart of recording start / end during insert recording according to the present invention.

FIG. 3 is a diagram showing a state of a track recorded on a tape in a standard mode and a long time mode according to the present invention.

FIG. 4 is a configuration diagram of a conventional magnetic recording / reproducing apparatus.

FIG. 5 is a timing chart of recording start / end during conventional insert recording.

FIG. 6 is a diagram illustrating a head arrangement on a drum according to the related art and the present invention.

FIG. 7 is a diagram illustrating a head width and a step according to the related art and the present invention.

FIG. 8 is a diagram showing a state of a track recorded on a tape in a conventional standard mode and a long time mode.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Rotation erase head (FE (flying erase) head), 2 ... Rotation audio head, 3 ... Video head for standard mode, 4 ... Video head for long time mode, 5 ... Gain adjustment circuit, 6 ... Audio recording amplifier, 7 ... Recording amplifier for standard mode, 8 ... Recording amplifier for long time mode, 9 ... Mode discriminating circuit, 10 ... Counter circuit, 11 ... Recording control circuit, 12 ...
Servo circuit, 13 AND circuit, 14-18 switch, a ₁ reproduction control signal (reproduction CTL signal),
b ₁ PG pulse signal.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) G11B 27/029 G11B 5/024 601 G11B 5/027

Claims (1)

(57) [Claims] 1. A magnetic recording / reproducing apparatus capable of insert recording, comprising: a rotary head for long-time mode video, a standard mode video, audio, and erasure, and a mode discriminating circuit for discriminating a recording mode of a recorded tape. in, a control circuit for outputting a control signal when the signal and insert a recording command from the mode discrimination circuit is input, a long time mode
If there is an insert command in the mode, the control circuit
Recorded track information by rotating head for audio according to control signal
Erase and insert with rotating head for long-time mode video
Record information and insert command in standard mode
Erases recorded track information with the rotating head for erasing.
Recording insert information with the rotating head for standard mode
The magnetic recording / reproducing apparatus characterized in that the switching selection is performed as described above .