JPH0414971A - Magnetic recording and reproducing device - Google Patents

Abstract

PURPOSE:To attain normal recording again onto a magnetic tape on which BGV is recorded once by providing a video recording, an audio recording circuit, a control recording and reproducing circuit and a BGV detection circuit to the device. CONSTITUTION:An output of a video head 5 is monitored in a short-play at start of video recording 2 and when a BGV detection signal is outputted from a BGV detection circuit 23 and no output of the video head 5 exists, only the video signal is recorded. Moreover, when the BGV detection circuit 23 outputs the BGV detection signal and the output of the video head 5 exists, the video signal, an audio signal and a control signal are recorded. Thus, even when a magnetic tape subject to once BGV recording is again recorded, the normal recording is easily implemented.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a magnetic recording and reproducing apparatus (hereinafter referred to as a VTR) that records and reproduces video and audio signals as discontinuous track loci inclined in the longitudinal direction of a magnetic tape. It is related to.

BACKGROUND OF THE INVENTION In recent years, VTRs have become increasingly high in image quality and multifunctional. One of its new functions is the ability to record video signals later on magnetic tape on which only audio signals have been previously recorded. This is called the BGM function.

The 807 function in a conventional magnetic recording/reproducing device will be described below with reference to the drawings.

FIG. 2 is a block diagram of 807 functions in a conventional magnetic recording/reproducing device. In FIG. 2, a recording mode command is input to the input 1a of the recording/reproduction mode control device 1, and a recording start/end command is input to the input 1b. The output 1d of the recording/playback mode control device 1 is connected to the input 2a of the video recording circuit 2, and the output 1e is connected to the input 3a of the audio recording circuit 3.
The output 1f is connected to the input 4a of the control recording/reproducing circuit 4. Output 2 of video recording circuit 2
b is connected to the video head 5, and the audio recording circuit 3
The output 3b of the control recording/reproducing circuit 4 is connected to the audio head 6, and the input/output 4b of the control recording/reproducing circuit 4 is connected to the control head 7.

Further, the output 1g of the recording/reproducing mode control device 1 is connected to the input 9a of the capstan control circuit 90, and the 8-power 9b is connected to the capstan motor 10.

Further, a BGV switch 11 for selecting the 807 function is connected to the input IC of the recording/reproducing mode control device 1. Note that the video head 5 and audio head 6 are attached to a rotating cylinder, and the control head 7 is fixed.

The operation of the above configuration will be described below.

First, an audio recording mode command is input to the input 1a of the recording/playback mode control device 1, and a recording start command is input to the input 1b.
, the recording/playback mode control device 1 outputs the output 1
A recording command is output from e to the input 3a of the audio recording circuit 3, and a recording command is output from the output 1f to the input 4a of the control recording/reproducing circuit 4. Outputs capstan information as shown. As a result, the audio recording circuit 3 sends a recording current to the audio head 6, the control recording/reproducing circuit 4 sends a recording current to the control head 7, and the capstan control circuit 9 causes the capstan motor 10 to rotate in the recording mode. Thereafter, when a recording end command is input to the input 1b of the recording/reproducing mode control device 1, the audio recording mode ends.

Next, a normal recording mode command is input to the input 1a of the recording/reproducing mode control device 1, and the BG■ switch 11
No BGV signal is input from the input 1b.
When input to
Eight recording commands are sent from d to the input 2a of the video recording circuit 2, from the output 1e to the input 3a of the audio recording circuit 3, from the output 1f to the input 4a of the control recording and reproducing circuit 4, and from the output 1g, the capstan control is performed. Input 9 of circuit 9
Capstan mode information is output to a to rotate the capstan in recording mode. As a result, the video recording circuit 2 supplies a recording current to the video head 5, the audio recording circuit 3 supplies a recording current to the audio head 6, and the control recording/reproducing circuit 4 supplies a recording current to the control head 7, and the capstan control circuit 9 supplies a recording current to the capstan motor IO. Rotate in recording mode. Thereafter, when a recording end command is input to the input 1b of the recording/reproducing mode control device 10, the normal recording mode ends.

Further, the normal recording mode command is input to the input 1a of the recording/reproducing mode control device 1, and the BGV switch 1)
A BGV signal is input from , and a recording start command is input 1b.
, the recording/playback mode control device 1 outputs the output 1
A recording command is output from d to the input 2a of the video recording circuit 2, g, a reproduction command is output from the output 1f to the input 4a of the control recording and reproducing circuit 4, and the output 1g outputs a reproduction command to the input 9a of the capstan control circuit 9. Outputs capstan mode information to rotate the capstan in playback mode. As a result, the video recording circuit 2 causes a recording current to flow through the video head 5, and the capstan control circuit 9 rotates the capstan motor 10 in the playback mode. and,
Thereafter, when a recording termination command is input to the input 1b of the recording/reproduction mode control device 1, the video recording mode is terminated.

In the conventional configuration described above, the BGV switch 11 must be operated when in video recording mode, but as a way to solve this problem, a BGV function in a magnetic recording and reproducing device that can automatically switch to video recording mode is considered. , which will be explained below.

FIG. 3 is a block diagram of the BGV function in the magnetic recording/reproducing apparatus, and the same components as in FIG. 2 are given the same reference numerals and their explanations will be omitted. In FIG. 3, the output 1f of the recording/reproducing mode controller 21 is connected to the input 4a of the control recording/reproducing circuit 22, and the output 2)a of the recording/reproducing mode controller 21 is connected to the input 22a of the control recording/reproducing circuit 22. When the connection is made and a reproduction command is input to the input 4a, the control recording/reproduction circuit 22 reproduces the control signal via the control head 7. Also, when a recording command is input to the input 4a and the input 22a
When a control duty modulation command is input to the input 4a, the control recording/reproducing circuit 22 records a control signal with a duty of 55:45 via the control head 7, and furthermore, a recording command is input to the input 4a, and
If no control duty modulation command is input to the input 22a, the control recording/reproducing circuit 22 records a control signal via the control head 7 with a normal duty of 60:40. The output 22b of the control recording and reproducing circuit 22 is connected to the input 23a of the BGV detection circuit 23, and the output 23b is connected to the input 21bl of the recording and reproducing mode control device 2I. When the control signal is monitored and the duty is determined to be 55:45, a BGV detection signal is output to the input 21b, and when the duty is determined to be 60:40, no BGV detection signal is output. .

The operation of the above configuration will be described below.

First, information indicating the audio recording mode is input to the input 1a of the recording/playback mode control device 21, and the input 1b
When a command to start recording is input to the input 3 of the audio recording circuit 3, the recording/playback mode control device 21 outputs the input 3 of the audio recording circuit 3 from the output 1e.
output a recording command to a, output a recording command from the output 1f to the input 4a of the control recording and reproducing circuit 22, and output a control duty modulation command from the output 21a to the input 22a of the control recording and reproducing circuit 22, Further, capstan mode information is output from the output 1g to the input 9a of the capstan control circuit 9 so as to rotate the capstan in the recording mode. As a result, the audio recording circuit 3 supplies a recording current to the audio head 6, the control recording/reproducing circuit 22 supplies a recording current to the control head 7 so as to record with a duty of 55:45, and the capstan control circuit 9 supplies a recording current to the control head 7 so as to record at a duty ratio of 55:45. 10
Rotate in recording mode. Thereafter, when a command to end recording is input to the input 1b of the recording and reproducing mode control device 21, the recording and reproducing mode control device 21 turns off the recording command that was output from the output 1e to the input 3a of the audio recording circuit 3. Then, the control recording/reproducing circuit 2 is controlled by the power 1f.
Turn off the recording command that was being output to input 4a of output 2.
The control duty modulation command output from 1a to the input 22a of the control recording/reproducing circuit 22 is turned off, and the capstan mode information is output from the output 1g to the input 9a of the capstan control circuit 9 to stop the rotation of the capstan. do. In this way, when the recording command inputted to the input 3a is turned off, the audio recording circuit 3 stops the recording current flowing to the audio head 6, and the control recording/reproducing circuit 22 stops the recording command inputted to the input 4a. When turned off, the recording current flowing to the control head 7 is stopped, and when capstan mode information is input to the input 9a to stop the rotation of the capstan motor 1G, the capstan control circuit 9 controls the capstan motor 10.
Stop 0 rotation.

Next, when the information that the normal recording mode is inputted to the input 1a of the recording/playback mode control device 21 and the command to start recording is inputted to the input 1b, the recording/playback mode control device 21 controls the recording/playback from the output 1f. A regeneration command is inputted to the input 4a of the circuit 22, and capstan mode information is outputted from the output 1g to the input 9a of the capstan control circuit 9 so as to rotate the capstan in the regeneration mode. When capstan mode information is input to the input 9a to rotate the capstan in the regeneration mode, the capstan control circuit 9 rotates the capstan motor 10 in the regeneration mode. The reproduction control signal from the control recording and reproduction circuit 22 is input to the BGV detection circuit 23.
3a. The BGV detection circuit 23 monitors the duty of the reproduction control signal and determines that the duty is 55:
When it is determined that the duty ratio is 45, a BGV detection signal is output from the output 23b to the input 21b of the recording/reproduction mode control device 10, and when it is determined that the duty is 60:40, the BGV detection signal is not output.

When the BGV detection signal is input to the input 21b, the recording/reproducing mode control device 21 outputs a recording command to the input 2a of the video recording circuit 2 from the input 1d, and the video recording circuit 2 passes a recording current to the video head 5. Thereafter, when a command to end recording is input to the input 1b of the recording and reproducing mode control device 21, the recording and reproducing mode control device 21 turns off the recording command that has been output from the output 1d to the input 2a of the video recording circuit 2. Then, the reproduction command outputted to the input 4a of the control recording/reproducing circuit 22 is turned off from the output 1f, and the capstan mode information is outputted from the output 1g so as to stop the rotation of the capstan motor 10.

Conversely, the recording/reproducing mode control device 21 inputs BG to the input 21b.
If the V detection signal is not input, a recording command is output from the output 1d to the input 2a of the video recording circuit 2, from the output 1e to the input 3a of the audio recording circuit 3, and from the output 1f to the input 4a of the control recording/reproducing circuit 22. A recording command is output, and a capstan mode command is output from the output 1g to the input 9a of the capstan control circuit 9 to rotate the capstan in the recording mode. As a result, the video recording circuit 2 causes a recording current to flow through the video head 5, the audio recording circuit 3 causes a recording current to flow through the audio head 6, and the control recording/reproducing circuit 22 causes the duty 60:
A recording current is applied to the control head 7 so as to record at 40, and the capstan control circuit 9 rotates the capstan motor 10 in recording mode. Thereafter, when a command to end recording is input to the input 1b of the recording/playback mode control device 21, the recording/playback mode control device 21 outputs 1
The recording command outputted to the input 2a of the video recording circuit 2 is turned off from d, the recording command outputted to the audio recording circuit 3 from the output 1e is turned off, and the recording command outputted from the output 1f to the input 4a of the control recording/reproducing circuit 22 is turned off. The output recording command is turned off, and capstan mode information is output so as to stop the rotation of the capstan motor 10 from the output 1g. The video recording circuit 2 stops the recording current flowing to the video head 5 when the recording command input to the input 2a turns off, and the audio recording circuit 3 stops the recording current flowing to the video head 5 when the recording command input to the input 3a turns off. When the recording current flowing through the control head 6 is stopped and the recording command input to the input 4a is turned off, the control recording/reproducing circuit 22 stops the recording current flowing through the control head 7, and the capstan control circuit 9 inputs the input 9a. When capstan mode information is input to stop the rotation of the capstan motor 10, the rotation of the capstan motor 10 is stopped.

Problems to be Solved by the Invention However, with the above configuration, when an attempt is made to record again on a magnetic tape on which BGV has been previously recorded, the BGV detection circuit 23 outputs a BGV detection signal, so only the video signal is recorded. The problem was that only normal recording was possible.

The present invention solves the above-mentioned problem, and aims to provide a magnetic recording and reproducing apparatus that can perform normal recording again on a magnetic tape that has been previously recorded with BGV.

Means for Solving the Problems In order to solve the above problems, the magnetic recording and reproducing apparatus of the present invention includes a video recording circuit that supplies a recording current to the video head when a recording command is input, and a video recording circuit that supplies a recording current to the video head when a recording command is input. An audio recording circuit that sends a recording current to the audio head, and a control signal that is played back from the control head when a playback command is input, and if a control duty modulation command is input when a recording command is input, it is normal. Record the control signal of another duty,
a control recording/reproducing circuit that records a normal duty control signal if the control duty modulation command is not input; and a BGV detection circuit when the duty of the input reproduction control signal is determined to be a duty different from the normal duty. A BGV detection circuit that outputs a signal, a video head output monitoring circuit that monitors the presence or absence of an output from the video head and outputs a head output detection signal if there is an output, and in the case of normal recording mode, normal recording mode information is input. and sends a reproduction command to the control recording and reproduction circuit, and the B
GV detection 8 signal is not input or the BGV detection 8 signal is not input.
When a signal is input and the head output detection signal is input, a recording command is sent to each of the audio recording circuit, video recording circuit, and control recording/reproducing circuit, and when the BGV detection signal is input and the head output When a detection signal is not input, a recording command is output to the video recording circuit, and a reproduction command is output to the control recording and reproducing circuit, and in the case of audio recording mode, audio recording mode information is input and the audio is output. The recording/reproducing mode control means outputs a recording command to the recording circuit, and outputs the recording command and the control duty modulation command to the control recording/reproducing circuit.

Operation With the above configuration, the output of the video head is monitored at the start of video recording and during short play, and if there is no output from the video head when the BGV detection signal is output from the BGV detection circuit, the video signal is records only, and also
When the BGV detection signal is output from the BGV detection circuit, if there is an output from the video head, the video signal, audio signal, and control signal are recorded.
Even when attempting to record again on a V-recorded magnetic tape, normal recording can be easily performed.

EXAMPLE Hereinafter, an example of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram of a magnetic recording/reproducing apparatus according to an embodiment of the present invention. Note that the same reference numerals are given to the same components as those in FIG. 3, and the explanation thereof will be omitted. An input 31a of the video head output monitoring circuit 31 is connected to the video head 5, and an output 31b is connected to an input 32a of the recording/reproduction mode control device 32.

With the above configuration, first, when information that the normal recording mode is input is input to the input 1a of the recording/reproducing mode control device 32, and a command to start recording is input to the input 1b, the recording/reproducing mode control device 32 outputs the output 1f. A reproduction command is outputted to the input 4a of the control recording and reproduction circuit 22, and capstan mode information is outputted from the output 1g to the input 9a of the capstan control circuit 9 so as to rotate the capstan in the reproduction mode. The capstan control circuit 9 rotates the capstan motor 10 in the regeneration mode when capstan mode information is input to the input 9a to rotate the capstan in the regeneration mode.

The control signal reproduced by the control recording and reproducing circuit 22 is input to the input 23a of the BGV detecting circuit 23. At this time, the BG detection circuit 23 monitors the duty of the playback control signal and finds that the duty is 55:
When it is determined that the duty is 45, the BGV detection signal is outputted from the output 23b to the input 21b of the recording/reproduction mode control device 32, and when it is determined that the duty is 6040, it is not output. On the other hand, the video head output monitoring circuit 31 monitors the output of the video head 5 and outputs a video head output detection signal if there is an output.

Furthermore, when the BGV detection signal is input to the input 21b and the video head output detection signal is not input to the input 32a, the recording/playback mode control device 32 outputs a recording command to the input 2a of the video recording circuit 2 from the input 1d. , the video recording circuit 2 supplies a recording current to the video head 5. Thereafter, when a command to end recording is input to the input 1b of the recording and reproducing mode control device 32, the recording and reproducing mode control device 32 turns off the recording command that was output from the output 1d to the input 2a of the re-video recording circuit 2. , and turns off the reproduction command output from the output 1f to the input 4a of the control recording/reproduction circuit 22, and outputs capstan mode information so as to stop the rotation of the capstan motor IO from the 8-force 1g.

Next, the recording/reproducing mode control device 32 inputs B to the input 21b.
If the GM detection signal is not input, or if the BGV detection signal is input but the video head output detection signal is input to the input 32a, the output]d is input to the input 2a of the video recording circuit 2, and the output 1e is input to the audio recording circuit. 3 input 3a
output a recording command to the input 4a of the control recording and reproducing circuit 22 from the output 1f, and output the recording command from the output 1g to the input 9a of the capstan control circuit 9 so as to rotate the capstan in the recording mode. Enter 8 capstan mode information. As a result, the video recording circuit 2 passes a recording current to the video head 5, the audio recording circuit 3 passes a recording current to the audio head 6, and the control recording/reproducing circuit 22 has a normal duty of 60:40.
A recording current is applied to the control head 7 so as to perform recording, and the capstan control circuit 9 controls the capstan motor 10.
Rotate in recording mode. Thereafter, when a command to end recording is input to the input 1b of the recording and reproducing mode control device 32, the recording and reproducing mode control device 32 transmits the recording command that was output from the output 1d to the input 2a of the video recording circuit 2. 8, turn off the recording command that was being output to the audio recording circuit 3 from the output 1e, turn off the recording command that was being output from the output 1f to the input 4a of the control recording and reproducing circuit 22, and output from ]-g. Capstan mode information is output so as to stop the rotation of the capstan motor 10. The video recording circuit 2 stops the recording current flowing to the video head 5 when the recording command input to the input 2a turns off, and the audio recording circuit 3 stops the recording current flowing to the video head 5 when the recording command input to the input 3a turns off. The control recording/reproducing circuit 22 stops the recording current flowing to the input 4.
When the recording command input to a is turned off, the recording current flowing to the control head 7 is stopped, and the capstan control circuit 9 inputs capstan mode information to the input 9a to stop the rotation of the capstan motor 10. Then, the rotation of the capstan motor 10 is stopped.

Effects of the Invention According to the present invention, the output of the video head is monitored at the start of video recording and during short play, and the output of the video head is monitored when the BGV detection signal is output from the BGV detection circuit. If there is no output, only the video signal is recorded, and if there is an output from the video head when the BGV detection signal is output from the BGM detection circuit, the video signal, audio signal, and control signal are recorded, thereby recording BGV once. Even when attempting to record on the magnetic tape again, normal recording can be performed.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of the BGV function in a magnetic recording and reproducing device according to an embodiment of the present invention, FIG. 2 is a block diagram of the BGV function in a conventional magnetic recording and reproducing device, and FIG. 3 is a block diagram of the BGV function in the magnetic recording and reproducing device. FIG. 2... Video recording circuit, 3... Audio recording circuit, 2... Video head, 22... Control recording/reproducing circuit, 23... BGV detection circuit, 31... Video head output monitoring circuit, 32 ... Recording/playback mode control device. Agent Yoshihiro Morimoto 1st-b Dote Saito 7r 2nd Moment

Claims (1)

[Claims] 1. A video recording circuit that supplies a recording current to the video head when a recording command is input, an audio recording circuit that supplies a recording current to the audio head when a recording command is input, and a video recording circuit that supplies a recording current to the audio head when a recording command is input. A control signal is reproduced from the control head, and if a control duty modulation command is input when a recording command is input, a control signal with a duty different from the normal one is recorded, and if the control duty modulation command is not input, a control signal with a different duty from the normal one is recorded. a control recording/reproducing circuit for recording a normal duty control signal; a BGV detection circuit for outputting a BGV detection signal when the duty of the input reproduction control signal is determined to be a duty different from the normal duty; A video head output monitoring circuit monitors the presence or absence of an output and outputs a head output detection signal if there is an output, and in the case of a normal recording mode, inputs normal recording mode information and outputs a reproduction command to the control recording and reproduction circuit. , the B from the BGV detection circuit
When a GV detection signal is not input, or when the BGV detection signal is input and the head output detection signal is input, a recording command is output to each of the audio recording circuit, video recording circuit, and control recording/reproducing circuit, and , when the BGV detection signal is input and the head output detection signal is not input, outputs a recording command to the video recording circuit, and outputs a reproduction command to the control recording and reproducing circuit, and in the case of audio recording mode. , a recording/reproducing mode control means receiving audio recording mode information and outputting a recording command to the audio recording circuit, and outputting a recording command and the control duty modulation command to the control recording/reproducing circuit. playback device.