JPH0432061A - Joint recording circuit device - Google Patents

Abstract

PURPOSE:To prevent the occurrence of the non-recording period by restarting recording by a control part after detecting the change of a recording area by a recording area detecting part. CONSTITUTION:When the temporary stop state is indicated by a system controller 3, the area where a pilot signal is recorded on a track of a magnetic tape is made different from that on the other tracks by a signal processing part 6; and when the recording state is started again, this area difference is detected by an ATF error signal generating circuit 1, and recording is started at this detection time. Thus, information is not recorded over another information on the magnetic tape, and the occurrence of a non-recording part between the preceding recording end part and the present recording start part is eliminated.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a splicing circuit device for a video tape recorder.

[Prior Art] In a video tape recorder (hereinafter referred to as VTR),
When performing so-called continuous shooting, in which the recording state and the paused state are repeated, the magnetic tape must be rewound a certain amount from the moment of pausing, in order to prevent disturbances in the reproduced image when playing back the continuous part. The operation is to start recording again. The amount of rewinding is controlled by counting the number of pulses of the control pulse signal and cab scan FG pulse signal recorded on the magnetic tape.

[Problem to be solved by the invention] However, if the accuracy control of the VTR mechanism is not sufficient, the erasing period of previously recorded information during snap-shots may become longer, or conversely, information may not be recorded. There was a problem in that a period of no records occurred.

The present invention has been made to solve these problems, and an object of the present invention is to provide a VTR continuous shooting circuit device in which the above-mentioned erasing period does not become long and no recording period occurs.

[Means for Solving the Problems] The present invention provides a splicing circuit device included in a video tape recorder that performs tracking control using the ATF method. a signal processing unit that changes the recording area of the pilot signal recorded in the signal processing unit; a recording area detection unit that detects a location where the recording area has been changed in the signal processing unit and sends a detection result signal to the control unit; When the magnetic tape enters the paused state, the signal processing unit is operated, and then the magnetic tape is moved a predetermined amount in the opposite direction to the forward running direction of the magnetic tape in the recording state, and then stopped, and the paused state is released. In some cases, the present invention is characterized by comprising a control section that operates the recording area detection section after running the magnetic tape in the forward running direction and puts the video tape recorder into a recording state based on the detection result signal.

[Function] When the recording state shifts to the pause state, the control unit:
The magnetic tape is run in a recording state for a predetermined amount, and the signal processing section is operated to make the recording area of the pilot signal recorded on the track different from the area recorded on other tracks. Thereafter, the control unit moves the magnetic tape in the opposite direction by a predetermined amount.

When the temporary stop state is released, the control section runs the magnetic tape in the forward running direction in the playback state, and operates the recording area detection section to detect the changed recording area. Then, the control section resumes recording information from the track after the track where the recording area was detected. in this way,
The signal processing section, the recording area detection section, and the control section restart recording after the change in the recording area is detected, so that the information erasure period does not become long and the non-recording period does not occur. ing.

[Embodiment] The splicing circuit device of the present invention detects a signal component having a frequency difference between a pilot signal recorded on a magnetic tape and a reference pilot signal, and detects a signal component having a frequency difference between a pilot signal recorded on a magnetic tape and a tracking error signal obtained from this signal component. A VTR that uses the so-called ATF method, which performs tracking control using
will be installed on the

In FIG. 1 showing an embodiment of the splicing circuit device of the present invention, a reference pilot signal generation circuit 2 that generates four types of reference pilot signals [1, f2, f3, f4, each having a different frequency, is used for recording Playback signal processing section 6
The recording/reproduction signal processing section 6 switches the four types of reference pilot signals f1, f2, J3, and f4 supplied for each field of the video signal to be recorded on the magnetic tape and records them on the magnetic tape together with the video signal. At the same time, it processes information signals recorded on the magnetic tape, and processes information signals reproduced from the magnetic tape on which information has already been recorded. Furthermore, when the recording/reproducing signal processing unit 6 is instructed to enter a so-called Bose mode in which the recording mode is temporarily interrupted, the system controller 3 (to be described later) sends out a control signal to set the so-called track on which the video signal etc. are recorded to the above-mentioned standard. Controls the range in which pilot signals are recorded.

That is, although the details will be described later, the recording/reproducing signal processing section 6
As shown in Figures B and C, before the Bose mode is instructed, the reference pilot signal is recorded over the entire scanning distance of each track, but for the tracks after the Bose mode is instructed, the α shown in the figure is used. The reference pilot signal is recorded in the scanning stroke of the track excluding the corresponding distance.

Such a reference pilot signal generation circuit 2 generates a tracking error signal based on the pilot signal reproduced from the magnetic tape supplied from the recording/reproduction signal processing section 6 and the reference pilot signal supplied from the recording/reproduction signal processing section 6. connected to the ATF error signal creation circuit 1 that creates
The ATF error signal generation circuit 1 is connected to the input side of a switch 4 whose contacts are switched by a switching signal sent by a system controller 3, as will be described later.

The contact terminal 4b of the switch 4 is connected to a capstan motor drive system circuit, and the capstan motor drive system circuit operates the capstan motor according to a tracking error signal supplied from the ATF error signal generation circuit 1 via the contact terminal 4b. control the rotation of

On the other hand, the contact terminal 4a of the switch 4 is connected to an error level determination circuit 5, and the error level determination circuit 5 is connected to the system controller 3. Error level judgment circuit 5
is an ATF error signal generating circuit 1 which is configured of, for example, a Schmitt circuit and is supplied via the contact terminal 4a.
The signal level of the tracking error signal sent out by the controller is compared with the reference signal level of the tracking error signal in the so-called just tracking state, and if the difference is within a predetermined level range, the low (L) level is set to If outside, a high (H) level signal is sent to the system controller 3.

The output side of the system controller 3 is connected to the reference pilot signal generation circuit 2, the recording/reproducing signal processing section 6, and the memory 7, and the main continuous shooting circuit is connected to the output side of the system controller 3 by being supplied with operation mode signals such as recording mode and Bose mode from the outside. In addition to controlling the operation of each component constituting the
As shown in C, the switch 4 is switched to the contact terminal 4b side for the period γ excluding the predetermined period β before the rise or fall of the RF-9W pulse signal, and the switch 4 is switched to the contact terminal 4a side for the period β. A switching signal is sent to switch 4. Note that the period β is longer than the above-mentioned period α, and the period α is included within the period β. Also, when Bose mode is instructed, the system controller 3 records the frequency of the reference pilot signal recorded on the last scanned track in the memory 7, and when the recording mode is instructed again, the frequency is stored in the memory 7. Read out the frequency.

The operation of the continuous shooting circuit device configured as described above will be described below.

When the recording mode signal is supplied to the system controller 3 and information is recorded on the magnetic tape, the four types of pilot signals fl, f243, and f4 sent out by the reference pilot signal generation circuit 2 are indicated by arrows a in FIG. b, c
, d, the video signal for one field is recorded over the entire scanning process of one track, and each pilot signal is varied for each field, and together with the video signal,
The recording/reproducing signal processing section 6 records the signal on the magnetic tape. In addition, each of the above four types of reference pilot signals is
It has the relationship shown below.

Δfa=lfl −f21=lf3−r4 l, Δrb
= f2 - f31 = l fl - f4 Also, as shown in Figs. 2 and 3, the above track is R
Each track is scanned in synchronization with the F-SW pulse signal.

Next, as shown in FIG. 2, if information is recorded on the magnetic tape in the above-mentioned recording mode up to track T3, and a Bose mode signal is supplied to the system controller 3 while recording track T4, the main splice The circuit device does not stop recording information at that point, as in the conventional example, but continues recording for a predetermined period of time. In this example, as shown in FIG. 2, the recording mode is continued until the scanning of the track T5 following the track T4 being scanned when the Bose mode signal is supplied is completed.

When scanning the next track T, the recording/reproducing signal processing unit 6 is controlled by the control signal supplied from the system controller 3 via the reference pilot signal generation circuit 2, and the recording/reproducing signal processing unit 6 is Instead of recording the pilot signal on the track over the entire track scanning process as in the case of other tracks, the pilot signal is recorded on the track for a predetermined period α minutes as shown by the arrow e in Figure 2C and Figure 3. Record shorter than the track. Note that the reference pilot signal recorded on track T5 has a frequency f1. In addition, the system controller 3 uses the frequency of the reference pilot signal recorded in a shorter area compared to other tracks, in this example, f as described above.
l, is stored in the memory 7. Also, the above period α is the second
As shown by A in the figure, this is a period whose end point is the time when the scanning of track T is completed. Then, in the above step A, the recording mode is temporarily interrupted, and the continuous shooting circuit is switched to the reproduction mode, as shown in the second diagram. As in the conventional example, the magnetic tape is rewound by a predetermined amount and then stopped. For ease of understanding, it is assumed that the above-mentioned rewinding has been performed up to the point where the above-mentioned track T1 is recorded.

Next, when the recording mode signal is supplied to the system controller 3 again, the system controller 3 first operates each component of the splicing circuit in the playback mode, and the previously recorded track and the new track after Bose mode is released. The tape running is controlled so that it is in phase with the track recorded on the tape. During this time, the capstan travel control is in the regeneration mode, and its phase control is performed by the known ATF method.

After the system controller 3 detects that the magnetic tape has started running and the capstan phase has been locked, the system controller 3 moves the R as shown in FIG.
In synchronization with the falling edges of the F-9W pulse signal, and the rising edges of the above signal, the contacts of the switch 4 are connected to the contact terminal 4 only for a predetermined period β in the direction that goes back in time from these times.
An H level switching signal for switching to the a side is sent to the switch 4. In other words, the track T4 and the fourth track shown in FIG.
As is clear from Figures B and C, the switch 4
switches the contact to the contact terminal 4a side. Furthermore, the above period β
The length of is somewhat longer than the above-mentioned period α. Furthermore, as shown in FIG. 4C, during the period γ, which is the period from the signal level change point of the RF-6W pulse signal to the next signal level change point, excluding the period β, the system controller 3 switches the switch. An L level switching signal is sent to the switch 4 to switch the contact 4 to the contact terminal 4b side. In other words, the switch 4 connects its contact to the contact terminal 4 for a period γ in the scanning direction from the scanning start point in each track.
Switch to side b.

Therefore, after locking the capstan phase, the RF
- Each track is sequentially regenerated and scanned in synchronization with the 8W pulse signal, and based on the regenerated reference pilot signal, a tracking error signal is created in the ATF error signal creation circuit 1 using a known method. The signal is sent from the ATF error signal generation circuit 1 to the capstan motor drive system via the contact terminal 4b of the switch 4 during a period γ from the start of track scanning. Therefore, the tracking motor drive system performs normal tracking control based on the supplied tracking error signal.

As shown in FIG. 3, as the track progresses and the magnetic head scans the section β' corresponding to the period β, the switch 4 closes its contact in response to the switching signal supplied from the system controller 3, as described above. Contact terminal 4 from contact terminal 4b
Switch to a. Also, the system controller 3
Sample and hold the tracking error signal just before it changes.

Therefore, in period β, A, TF error signal generation circuit 1
The tracking error signal created in
The signal is supplied to the error level determination circuit 5 via the contact terminal 4a. Therefore, during the scanning of the track section β°, the above tracking error signal is not used for tracking control, and the tracking control during this period is as follows:
This is done using the sampled and held tracking error signal mentioned above.

The error level determination circuit 5 compares the signal level of the tracking error signal supplied as described above with the reference signal level of the tracking error signal that is the reference in the just tracking state, and determines the H level or L level depending on the difference. The signal is sent to the system controller 3. As mentioned above, in this example, recording of information is interrupted at track T5, so when scanning from track T to a predetermined position on track T5, as shown in Figure 4, the information is supplied to the error level determination circuit 5. The signal level of the tracking error signal generated is almost the same as the reference signal level. Therefore, during this period, the error level determination circuit 5 sends an L level signal to the system controller 3, and the system controller 3 does not perform the operations described below.

When the magnetic head scans the track T, the track T
The scanning proceeds from track T4 in the same manner as in the case of track T4, and as shown in FIG. 4, at time t5, the contact of switch 4 is switched to contact terminal 4a by a switching signal supplied from system controller 3.

As the scanning progresses further, the magnetic head scans a section α' in the track T corresponding to the period α, as shown in FIG. As mentioned above, since the reference pilot signal f1 is not recorded in the period α, the signal created by the ATF error signal creation circuit 1 from the time the scanning of the interval α° is started is only the signal of Δfa, and the ATF error signal f1 is not recorded. The tracking error signal sent out from the signal generating circuit 1 instantaneously changes to a value greater than the reference signal level at time t6, as shown in the fourth diagram. The tracking error signal that has changed in this way is supplied to the error level determination circuit 5 via the contact terminal 4a of the switch 4, and the error level determination circuit 5 compares the reference signal level with the signal level of the tracking error signal that has changed. do. Since the difference between these signal levels exceeds a predetermined range, the error level determination circuit 5 lowers the signal level sent to the system controller 3 to L as shown at time t6 in FIG. 4E.
Change from level to H level.

By being supplied with the H level signal, the system controller 3 synchronizes with the change point of the RF-9W pulse signal immediately after the H level signal is supplied, as shown at time t7 in FIG. 4F. At this timing, the components are changed from the playback mode to the recording mode, and each component is operated. Regarding the frequency of the reference pilot signal recorded on the track when changing to the recording mode, in this example, the system controller 3 reads out the frequency f2 next to the frequency fl stored in the memory 7, and sets the frequency f2. The four types of frequencies described above are sequentially recorded on each track.

In the above-described embodiment, the frequency of the reference pilot signal recorded on the track T after shifting to Bose mode is set to fl, but of course this is not limited to this, and other frequencies may be used. Further, the time length of the period α during which no reference pilot signal is recorded after transition to the Bose mode can be set at any position on the track, for any period, and for any number of periods within a range that does not interfere with tracking control. However, the period α
When the magnetic head scans the section of the track corresponding to It is necessary to take into consideration that the period β starts from the beginning.

In this way, when the Bose mode is instructed when performing continuous shooting, the area where the reference pilot signal is recorded on the track on the magnetic tape is made different from the above area on other tracks, and when the recording mode is started again. Since the difference in this area is detected and recording starts from the moment it is detected, information is not recorded overlappingly on the magnetic tape, and there is no recording between the part where the previous recording ended and the part where the current recording starts. No parts occur at all.

Furthermore, when the splicing circuit device of the present invention is used in a conventional ATF type VTR, the conventional circuit part related to ATF control can be used as is, and the number of newly added parts is small and the circuit configuration is simple. Great effects as described above can be obtained.

[Effects of the Invention] As described in detail above, according to the present invention, the area in which a pilot signal is recorded in a track on a magnetic tape when a pause state is instructed is made different from the area in other tracks, When the recording state starts again, it will detect the difference in this area and start recording at the moment it is detected.
Information is not recorded overlappingly on the magnetic tape, and it is possible to prevent unrecorded portions from occurring between the previous recording end portion and the current recording start portion.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the configuration of an embodiment of the splicing circuit device of the present invention, FIG. 2 is a first degree time chart explaining the operation of the splicing circuit device shown in FIG. 1, and FIG. 4 is a diagram showing the state of tracks recorded on a magnetic tape by the splicing circuit device shown in FIG.
This figure is a time chart for explaining the operation of the continuous shooting circuit device shown in FIG. Fig. 1 I: ATF error signal generation circuit, 3: System controller, 4: Switch, 5:
. . Error level determination circuit; 6. Recording/reproduction signal processing section.

Claims (1)

[Claims] (1) In a splicing circuit device installed in a video tape recorder that performs tracking control using the ATF method, when the recording state shifts to the pause state, the recording area of the pilot signal recorded on the track on the magnetic tape is a signal processing unit for changing the recording area; a recording area detection unit for detecting the location where the recording area has been changed in the signal processing unit and sending a detection result signal to the control unit; After operating the signal processing unit, the magnetic tape is moved a predetermined amount in the direction opposite to the forward running direction of the magnetic tape in the recording state and then stopped, and when the paused state is released, the magnetic tape is moved in the forward running direction. A continuous shooting circuit device comprising: a control section that operates the recording area detection section after running the video tape recorder and puts the video tape recorder in a recording state based on the detection result signal.