JPH0516092B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a magnetic tape dubbing method, in which a program-to-program detection signal is inserted between programs to record continuously on a magnetic tape, and the recorded magnetic tape is The present invention aims to provide a magnetic tape dubbing method in which each magnetic tape is of uniformly high quality by detecting a detection signal and cutting the tape, and the work process is simplified and automated.

Conventionally, when manufacturing a large number of soft tapes by dubbing audio and video signals (hereinafter simply referred to as "video signals") reproduced from a master tape onto cassette-type magnetic tapes such as VHS format, As shown in Figure 1, an unrecorded magnetic tape (hereinafter referred to as "raw tape") with a length of several thousand meters
After steps A and B of making a plurality of cassette tapes wound with magnetic tape of a desired length,
A step C is performed in which a video signal is dubbed onto a master tape for each cassette tape, and a rear cassette tape inspection step D, a rewinding step E, and a rear cassette tape inspection step D, a rewinding step E, A front cassette tape inspection process F was performed, followed by a labeling and case placement process G and a finishing process H. If the recording time of the program recorded on each cassette tape matches that of a commercially available unrecorded cassette tape, you can use this commercially available cassette tape, but if they do not match, there will be excess magnetic tape. This would be uneconomical, and in order to avoid surplus, cassette tapes were made using magnetic tapes that matched the recording time of the program. Therefore, when the number of cassette tapes on which the same program is recorded is small, the efficiency is low. In addition, individual cassette tapes have variations such as warping of the casing and bending of the shaft of the guide roller, and these variations affect the recording quality, so a large amount of man-hours are required to check the quality after recording. It is necessary to inspect the recording state of the cassette tape near the start and end points of recording. Furthermore, since recording is performed using a cassette tape, a cassette tape rewinding step E is required to locate the beginning of recording. Additionally, there is a risk of damaging the cassette when loading and unloading the cassette tape into the recording device, and automating cassette tape recording requires the cassette loading and unloading mechanism, transport equipment, storage space for the cassette tape, etc. In addition, if the program to be recorded on the cassette tape is short, it is difficult
There was a drawback that the ratio of time required for detachment became large, resulting in poor efficiency.

The present invention eliminates the above-mentioned drawbacks,
One embodiment thereof will be explained with reference to FIG. 2 and the following figures.

FIG. 2 shows a process diagram of one embodiment of the magnetic tape dubbing method according to the present invention. In the figure, a long raw tape with several thousand meters of unrecorded magnetic tape wound on it is one or more programs played from a master tape that are repeatedly recorded continuously without being cut off. (Step I). After the long recorded tape has been recorded, the recording condition near the end of recording is inspected in step J to see if the gap in the recording head has not become clogged during recording, and then the recording tape is inspected from one end of the tape where recording has been completed. The tape is wound up and cut into program units (step K), and recorded cassette tapes are assembled from the cut recorded tapes (step L). A portion of the plurality of recorded cassette tapes manufactured in this way is extracted and its recording state is inspected (Step M), and in the next Step G, each recorded cassette tape is labeled,
A sticker with the program name printed on it is pasted on it, it is placed in a case, and it is shipped after going through finishing process H.

Continuous dubbing, which is the main part of the method of the present invention shown in FIG. 2, is performed by the apparatus shown in FIG.

Figure 3 shows one of the dubbing devices used in the present invention.
A block system diagram of an example is shown. In the figure, 1 is a reference signal generator, which generates, for example, an NTSC color vertical synchronization signal and horizontal synchronization signal based on a constant frequency signal generated by a built-in oscillator, and supplies the generated signals to playback devices 2 and 3. At the same time, a black burst signal consisting of a vertical synchronization signal, a horizontal synchronization signal and a color burst signal and containing no image signal is generated and supplied to the switch circuit 4 and the frame pulse generation circuit 5. The playback devices 2 and 3 are controlled by a playback control signal from a central processing unit (hereinafter referred to as (CPU)) 6, which will be described later. Play in sync with the signal. The video signals reproduced by the reproduction devices 2 and 3 are supplied to a switch circuit 4 and a frame pulse generation circuit 5, respectively. The frame pulse generation circuit 5 divides the vertical synchronization signal of the black burst signal by 1/2 to generate a first frame pulse with a pulse width of about 1 μs to several μs,
In addition to supplying it to the CPU 6, the frequency of the vertical synchronization signal of the video signal from the reproduction device 2 or 3 is divided by 2 to generate a second frame pulse having a pulse width of approximately 1 μs to several μs, and the generated second frame pulse is supplied to the CPU 6.

The CPU 6 constantly counts the first frame pulses generated from the black burst signal, and also counts the second frame pulses when the playback devices 2 and 3 are in the playback mode, and counts the first frame pulses generated from the black burst signal. By comparing the pulse count value with the value stored in advance in the memory built into the CPU 6, a playback control signal is generated to control playback start, stop, rewind, etc. of each of the playback devices 2 and 3, and the playback device 2 and 3, and also supplies a switch control signal to the switch circuit 4 to control the switching of the switch circuit 4, and controls the start and stop of recording of the recording devices 7, 8, and 9, and the cutting position of the recorded tape, which will be described later. A recording control signal is supplied to the recording devices 7, 8, and 9 to control recording of a queue signal, which is an inter-program detection signal for instructing. Further, the switch circuit 4 extracts the signal instructed by the switch control signal from among the video signals and black burst signals supplied from the playback devices 2 and 3, and sends it to the distributor 10.
supply to. The distributor 10 supplies the signal from the switch circuit 4 to the recording devices 7, 8, and 9, respectively. Each of the recording devices 7, 8, and 9 has a built-in cue signal generator, and records the video signal, black burst signal, and cue signal from the playback devices 2, 3 on the raw tape set in each of them.

Next, one embodiment of the dubbing order of the magnetic tape by the apparatus shown in FIG. 3 will be described. The CPU 6 generates a switch control signal to select a black burst signal, and also generates a recording control signal to indicate the start of recording, and outputs the magnetic tape 11 shown in FIG. The black burst signal is recorded in the video signal recording portion. As a result, the portion 11a on the magnetic tape 11
A black burst signal is recorded. CPU
6 controls the playback device 2 to start playback when the count value of the first frame pulse reaches a set value, and the switch circuit 4 to select the video signal from the playback device 2;
A video signal from the reproducing device 2 is recorded on a portion 11b on the magnetic tape 11. CPU6 is playback device 2
When it is detected from the count value of the second frame pulse based on the video signal that the playback of the master tape in the playback device 2 will soon end, the playback device 3 is started to play the master tape, and the playback of the master tape in the playback device 2 is started. At the same time as the playback ends, the switch circuit 4 controls the video signal from the playback device 3 to be selected, and then the master tape in the playback device 2 is rewound. As a result, the video signal from the reproducing device 3 is recorded on the portion 11c on the magnetic tape 11 consecutively with the video signal from the reproducing device 2.

When the CPU 6 detects from the count value of the second frame pulse that the playback of the master tape in the playback device 3 has ended and the first dubbing of the program has ended, the switch circuit 4 selects and extracts the black burst signal. After that, the master tape of the playback device 3 is rewound. When a predetermined number of first frame pulses arrive after counting of second frame pulses is interrupted, the CPU 6 generates a cue signal to the recording devices 7, 8, and 9, and converts this cue signal into a black burst signal. They are superimposed and recorded on the raw tape 11. The queue signal, which is a signal for detecting between programs, has a repetition frequency of 10 to
This pulse has a frequency of 20 Hz and has a level that saturates the magnetic tape during the high level period.
After the recording devices 7, 8, and 9 have generated the cue signal for a predetermined period of time, the CPU 6 stops the generation of the cue signal, and further records a black burst signal while a predetermined number of first frame pulses are received. let me,
Thereafter, the control is performed again to record the video signal from the reproducing device 2, and the above control is repeated. A black burst signal is recorded on a portion 11d on the magnetic tape 11 shown in FIG.
A cue signal is recorded superimposed on the black burst signal in part e, and a video signal from the playback device 2, which is the second damping of the program, is recorded in part 11f.

The long recorded tape recorded in this way by the apparatus shown in the third figure is wound up from one end where recording has been completed without being rewound. During this winding, the long pre-recorded tape is brought into contact with only the video signal recording area (or slightly raised above the tape), excluding the audio signal and control signal recording area.
Then, only the recorded portion of the video signal is reproduced by a magnetic head having a cutoff frequency _fH expressed by the following equation.

2f _cue・N≦f _H …(1) f _H <f _V …(2) Here, f _cue is the repetition frequency of the cue signal,
N is the double speed of the tape running speed during winding relative to the tape running speed during recording, and _fV is the lowest frequency of the video signal (not including the audio signal). Therefore, only the cue signal is reproduced by this magnetic head, and when the pulses of this cue signal are reproduced numerically in succession, for example, a certain point on the recorded tape is set at a position that the magnetic head passes after being reproduced. The cutter is activated and the recorded tape is cut. A broken line I in FIG. 4 indicates the tape cutting position, and a portion 11 where the queue signal is recorded from the broken line I.
The distance a to one end of e is less than several centimeters.
As shown in FIG. 5, a leader tape 12 is attached to the left side of this tape cutting part and incorporated into a cut casing (not shown). The reproducible portion is to the right of the dashed line in FIG. 5, and the queue signal recording portion 11e is not reproduced.

In the above embodiment, the video signals of the playback devices 2 and 3 are consecutively set as one program, but for example, the video signal of the playback device 2 and the video signal of the playback device 3 may be separate programs. Further, the number of playback devices may be one or three or more, the number of recording devices may be one, two, or four or more, and the second frame pulse is transmitted to the playback devices 2 and 3.
It may be generated using a different control signal, and is not limited to the above embodiment. Further, although the tape cutting position in FIG. 4 is for the VHS system, in other systems, this cutting position may be within the portion 11d on the right side of the portion 11e.

As described above, the magnetic tape dubbing method according to the present invention inserts a program-distinguishable inter-program detection signal between the beginning and end of each program repeatedly supplied from a playback device, thereby dubbing a long, unused program. The inter-program detection signal is continuously recorded on a recording magnetic tape, and the inter-program detection signal is reproduced while winding the recorded magnetic tape from the rear end, without erasing the inter-program detection signal. One program is recorded by cutting the magnetic tape near the detection point and at a portion where the inter-program detection signal cannot be reproduced by the playback device when one end of the recorded magnetic tape is assembled into the housing. In order to obtain a cut magnetic tape, the unrecorded magnetic tape has no scratches or dust on it before the program signal recording process, so there is no dropout of the program signal, resulting in high quality. The recording state of the magnetic tape is uniform, unaffected by variations in the cassette housing, etc., and there is no need for rewinding, and the cut magnetic tape can be sampled and inspected, simplifying the process. This method enables automation throughout the process and is suitable for mass production.Furthermore, the casing that houses the cut magnetic tapes is not damaged and its appearance does not deteriorate.

[Brief explanation of the drawing]

Figure 1 shows one of the conventional magnetic tape dubbing methods.
FIG. 2 is a process diagram of one embodiment of the method of the present invention, FIG. 3 is a block system diagram of one embodiment of a dubbing device used in the method of the present invention, and FIGS. 4 and 5 are FIG. 3 is a diagram schematically showing recording signals on a magnetic tape recorded by the apparatus shown in FIG. 1... Reference signal generator, 2, 3... Reproduction device,
4... Switch circuit, 5... Frame pulse generation circuit, 6... CPU, 7, 8, 9... Recording device,
10...Distributor, 11...Magnetic tape, 12...
Leader tape, I... Continuous dubbing process, J...
... Rear reel inspection process, K... Winding and cutting process.

Claims (1)

[Claims] 1. A method for continuously recording a long unrecorded magnetic tape by inserting an inter-program detection signal distinguishable from the program between the beginning and end of each program repeatedly supplied from a reproducing device. and reproducing the inter-program detection signal while winding the recorded magnetic tape from the rear end, and reproducing the inter-program detection signal near the detection point of the inter-program detection signal without erasing the inter-program detection signal. and one program is recorded by cutting the magnetic tape at a portion where the inter-program detection signal cannot be reproduced by a playback device when one end of the recorded magnetic tape is assembled into a housing. A magnetic tape dubbing method characterized in that a magnetic tape is obtained.