JPH0896305A - Magnetic recording and reproducing device - Google Patents

Abstract

PURPOSE: To obtain a reproduced signal corresponding to the performance of a magnetic tape by individually providing a DC power source to be used for an erasing means and a DC power source to be used for a recording means. CONSTITUTION: This device is equipped with an erasing means DC2 for erasing a signal on a recording track by passing a high frequency current through a 1st magnetic head 4a mounted on a rotary drum 5 in the traveling stop state of a magnetic recording medium 6 and the recording means DC1 for recording a prescribed signal by a 2nd magnetic head 4b mounted on the rotary drum 5, having an opposite azimuth to the 1st magnetic head 4a on the recording track where the signal is erased by the means DC2. The signal recorded by the recording means DC1 is immediately reproduced by the 2nd magnetic head 4b, and the recorded signal is detected by a detecting means with a preapmlifier 8 and a reproducing FM detector 9. The device is also equipped with a microcomputer 10 as a discriminating means for discriminating a signal recording and reproducing characteristic of the magnetic recording medium 6 based on an output result of the detecting means 8 and 9.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention discriminates the performance of a magnetic recording medium in order to record and reproduce the signal on the magnetic recording medium in an optimum state, and thereby performs the signal recording process and the signal reproducing process. The present invention relates to a magnetic recording / reproducing device for controlling.

[0002]

2. Description of the Related Art In a VTR for recording a video signal on a magnetic recording medium such as a magnetic tape, there is a function of discriminating the performance of the magnetic tape in order to record a desired video signal in an optimum state.

As a method for discriminating the performance, a signal for discriminating a tape is recorded on a magnetic tape and recorded on a magnetic tape before recording a desired video signal. There is something that distinguishes such things.
Then, a magnetic recording / reproducing apparatus capable of finishing the performance determination of the magnetic tape in a short time to start a recording operation and performing a signal recording process according to the performance of the magnetic tape (Japanese Patent Laid-Open No. Hei.
No. 314408) was proposed.

[0004]

However, in the magnetic recording / reproducing apparatus described above, a video signal is supplied to the magnetic tape for a short time (about 0.5 seconds or a time when there is no problem in discrimination performance) while the magnetic tape is stopped. After recording, the recorded video signal is read and reproduced from the magnetic tape in a stopped state for a predetermined time (about 0.5 seconds or a time when there is no problem in the discrimination performance), and the performance of the magnetic tape is discriminated. However, it can be said that the time required for determining the performance of the magnetic tape is not yet the shortest in terms of technology (no disclosure is suggested about performing performance determination that shortens the time of at least about 0.5 seconds).

Further, when recording a signal on a magnetic tape, pre-erasure is performed in order to ideally reproduce the recorded signal in order to prevent the influence of the signal component on the magnetic tape. As for erasing when recording a signal for tape discrimination, no disclosure or suggestion is made, so there is a problem in that a problem remains from a practical point of view.

Therefore, it has been desired to develop a magnetic recording / reproducing apparatus that technically minimizes the time required for determining the performance of the above-mentioned magnetic tape and eliminates the above-mentioned inconvenience.

[0007]

Therefore, in order to solve the above-mentioned problems, the present invention provides the following configurations (1) to (5). (1) Signal recording processing means (recording system signal processing circuit 13) for recording a signal on a recording track (track pattern TP) formed on a magnetic recording medium (magnetic tape 6),
In a magnetic recording / reproducing apparatus provided with a signal reproduction processing means (reproduction system signal processing circuit 14) for reproducing a signal recorded on the recording track, the rotating drum 5 is provided with the magnetic recording medium 6 in a stopped state. Erasing means (DC power supply DC2, FM modulator 1, recording amplifier 2) for erasing the signal on the recording track TP by passing a high-frequency current through the mounted first magnetic head 4a, and the erasing means DC2, 1 Recording means (DC power source) for recording a predetermined signal on the recording track TP from which the signal has been erased by the first magnetic head 4a and the second magnetic head 4b mounted on the rotary drum 5 having a reverse azimuth. DC1, FM modulator 1, recording amplifier 2)
And a detection means (preamplifier 8, which detects the recorded signal by immediately reproducing the signal recorded by the recording means DC1, 1, 2 by the second magnetic head 4b).
Magnetic recording comprising a reproducing FM detector 9) and a discriminating means (microcomputer 10) for discriminating the signal recording / reproducing characteristics of the magnetic recording medium 6 based on the output results of the detecting means 8 and 9. Playback device. (2) Recording track TP formed on the magnetic recording medium 6
In a magnetic recording / reproducing apparatus equipped with a signal recording processing means 13 for recording a signal on a recording medium and a signal reproduction processing means 14 for reproducing a signal recorded on the recording track TP, the magnetic recording medium 6 is run. Erasing means DC for erasing the signal on the recording track TP by applying a high frequency current to the first magnetic head 4a mounted on the rotating drum 5 in the stopped state.
2, 1 and 2 and the recording track TP from which the signals have been erased by the erasing means DC2, 1, 2 are rotated with a predetermined signal with a plurality of gains set and with the first magnetic head 4a and an inverse azimuth. Recording means DC1, 1, 2 for recording by the second magnetic head 4b mounted on the drum 5, and the recording means DC1,
Detecting means 8, 9 for immediately reproducing the signal recorded by 1, 2 by the second magnetic head 4b and detecting the signal having the maximum level among the reproduced predetermined signals.
Then, the signal recording / reproducing characteristics of the magnetic recording medium 6 are discriminated from the output results of the detecting means 8 and 9, and the signal recording processing means 13 is controlled at the time of recording based on the discrimination result, and the signal reproducing at the time of reproducing is performed. The control means 10 controls the processing means 14, and the control means 10 compares the preset reference value with the detection results of the detection means 8 and 9 to thereby record the signal recording processing means 13 at the time of recording. The magnetic recording / reproducing apparatus characterized by controlling the signal reproduction processing means 14 during reproduction. (3) Recording track TP formed on the magnetic recording medium 6
In a magnetic recording / reproducing apparatus equipped with a signal recording processing means 13 for recording a signal on a recording medium and a signal reproduction processing means 14 for reproducing a signal recorded on the recording track TP, the magnetic recording medium 6 is run. Erasing means DC for erasing the signal on the recording track TP by applying a high frequency current to the first magnetic head 4a mounted on the rotating drum 5 in the stopped state.
2, 1 and 2 and the recording track TP from which the signals have been erased by the erasing means DC2, 1, 2 are rotated with a predetermined signal with a plurality of gains set and with the first magnetic head 4a and an inverse azimuth. Recording means DC1, 1, 2 for recording by the second magnetic head 4b mounted on the drum 5, and the recording means DC1,
Detecting means 8, 9 for immediately reproducing the signal recorded by 1, 2 by the second magnetic head 4b and detecting the signal having the maximum level among the reproduced predetermined signals.
Then, the signal recording / reproducing characteristics of the magnetic recording medium 6 are discriminated from the output results of the detecting means 8 and 9, and the signal recording processing means 13 is controlled at the time of recording based on the discrimination result, and the signal reproducing at the time of reproducing is performed. And a control means 10 for controlling the processing means 14, the erasing means DC2, 1, 2 and the recording means DC1, 1,
Reference numeral 2 is a magnetic recording / reproducing apparatus, which outputs an erasing signal and a recording signal based on independent DC voltage signals. (4) At least a magnetic head for erasing a signal on the recording track TP, and the recording track TP after the erasing
The magnetic head for recording / reproducing the predetermined signal is always in a reverse azimuth relationship with the above (1).
(3) The magnetic recording / reproducing device according to (3). (5) The erasing means DC2, 1, 2 is the first or second
The magnetic heads 4a, 4b erase the signal on the recording track TP in synchronization with the timing of scanning the magnetic recording medium 6, and the recording means DC1, 1, 2 are The magnetic recording according to any one of (1) to (4) above, wherein a recording signal is recorded on the recording track TP in synchronization with a timing at which the magnetic head having a reverse azimuth relationship scans the magnetic recording medium 6. Playback device.

[0008]

1 is a block diagram for explaining a first embodiment of a magnetic recording / reproducing apparatus according to the present invention, FIG. 2 is a time chart for explaining the operation of the magnetic recording / reproducing apparatus according to the present invention, and FIG. FIG. 4 is a diagram for explaining a tape pattern relating to the operation of the magnetic recording / reproducing apparatus according to the present invention, FIG. 4 is a block diagram for explaining a second embodiment of the magnetic recording / reproducing apparatus according to the present invention, and FIG. FIG. 6 is a block diagram for explaining the third embodiment of the recording / reproducing apparatus, and FIG. 6 is a time chart for explaining the operation of the magnetic recording / reproducing apparatus of the present invention. Hereinafter, the magnetic recording / reproducing apparatus according to the present invention will be described in Examples 1 to 3 with reference to the drawings. The same components as those described above are designated by the same reference numerals, and the description thereof will be omitted.

(First Embodiment) As shown in FIG. 1, a magnetic recording / reproducing apparatus according to the present invention is a magnetic recording medium (magnetic tape).
Recording track (track pattern) TP formed on 6
Signal recording processing means (recording system signal processing circuit 13) for recording a signal on the track and signal reproduction processing means (reproduction system signal processing circuit 14) for reproducing the signal recorded on the track pattern TP. In the magnetic recording / reproducing apparatus, an erasing means (DC power supply) for erasing the signal on the track pattern TP by applying a high frequency current to the first magnetic head 4a on which the rotating drum 5 is mounted while the magnetic tape 6 is stopped.
DC2, FM modulator 1, recording amplifier 2) and this erasing means
Track pattern with signal canceled by DC2, 1, 2
Recording means (DC power supply DC1, FM modulator 1, recording amplifier 2) for recording a predetermined signal on the TP by the second magnetic head 4b mounted on the rotary drum 5 having the first magnetic head 4a and the reverse azimuth. ) And a detection means (preamplifier 8, reproduction FM detector 9) for immediately reproducing the signal recorded by the recording means DC1, 1, 2 by the second magnetic head 4b and detecting the recorded signal, A discriminating means (microcomputer; also called a microcomputer) 10 for discriminating the signal recording / reproducing characteristics of the magnetic tape 6 based on the output results of the detecting means 8 and 9 is provided.

Now, for example, when an instruction is input from the user to the microcomputer 10 to determine the performance of the magnetic tape 6 (for example, magnetic characteristics for recording and reproducing signals), the microcomputer 10 drives the magnetic tape to run. Control is performed so as to stop driving of the magnetic tape running system (not shown). By this control, the capstan (not shown) included in the above-described magnetic tape running system stops the running of the magnetic tape, and the drum servo (not shown) included in the above-described magnetic tape running system causes the above-described first and second drum servos. The rotation of the rotary drum 5 on which the magnetic heads 4a and 4b are mounted is maintained. The drum pulse output from this drum servo is supplied to the microcomputer 10.

Here, the first and the first mounted on the rotary drum 5
The second magnetic heads 4a and 4b are, for example, in a positional relationship of facing each other by 180 ° on the rotating drum 5, and the respective magnetic heads have mutually different azimuth angles so that adjacent track patterns interfere with each other. It is possible to record and reproduce a signal on a track pattern corresponding to each magnetic head without (occurrence of crosstalk).

A drum pulse as shown in FIG. 2 is supplied to the microcomputer 10. This drum pulse is, for example,
Channel 1 (ch1, "Lo" generated based on a synchronization signal included in a video signal input to the magnetic recording / reproducing apparatus).
w ”signal) and channel 2 (ch2,“ Hi ”signal) two pulse signals. The rotation of the rotary drum 5 is controlled so as to be synchronized with this signal, and the first and second signals are mounted on the rotary drum 5. The second magnetic heads 4a and 4b scan the magnetic tape 6. For example, the first magnetic head 4a is synchronized with the timing when the drum pulse is obtained by the "Hi" signal.
Scans the magnetic tape 6. Similarly, the drum pulse is synchronized with the timing obtained by the signal of "Low", and the second
Magnetic head 4b scans the magnetic tape 6.

The microcomputer 10 has the following switch control signals (A) and (C) in response to the above-mentioned drum pulse.
Are supplied to the changeover switches 12 and 3, respectively. For example, ch
When the output of the changeover switch 12 is switched to the c side by the switch control signal (A) corresponding to the pulse of 2, the voltage signal from the DC power supply DC2 is supplied to the FM modulator 1.

The FM modulator 1 modulates the voltage signal from the DC power supply DC2 into a high frequency signal. Where this DC power supply DC
The value of the voltage output by 2 is a predetermined voltage value for obtaining a high frequency signal having a frequency sufficient to erase the signal on the magnetic tape 6.

The high frequency signal output from the FM modulator 1 is supplied to the recording amplifier 2, amplified to a predetermined gain, and output to the changeover switch 3. The change-over switch 3 supplies the high-frequency signal supplied to the R side by the switch control signal (C) (for example, a "Hi" signal) from the microcomputer 10 to the head change-over switch 7 as an erase signal. The changeover switch 7 changes over and supplies the signals supplied in synchronism with the above-mentioned drum pulse timing to the first and second magnetic heads 4a and 4b (or alternatively, the erase signal is supplied to the first magnetic head 4a). May be supplied only to).

At this time, the rotary drum 5 rotates halfway, and, for example, the above-mentioned first magnetic head 4a scans the track pattern TP on the magnetic tape 6, so that the above-mentioned erase signal is recorded on this track pattern TP. It That is,
The signal on the track pattern TP is erased (shown in FIG. 3A).

When the rotary drum 5 is half-rotated next and a pulse of ch1 is supplied to the microcomputer 10 (a state in which the second magnetic head 4b scans the track pattern TP),
This microcomputer 10 outputs the above-mentioned switch control signal (A) and switches the changeover switch 12 to the b side. The changeover switch 12 receives the voltage signal from the DC power supply DC1 by the switch control signal (A),
Supply to the modulator 1. The voltage of the DC power supply DC1 is set to a predetermined reference value, is FM-modulated by the FM modulator 1, and is supplied to the R side of the changeover switch 3 via the recording amplifier 2 as described above. At this time the microcomputer
Reference numeral 10 maintains the switch control signal (C) in the "Hi" state, and supplies the signal supplied to the R side to the head changeover switch 7. The head changeover switch 7 uses this signal as a recording signal for the first and second magnetic heads 4a, 4b.
(Or, in this case, only the second magnetic head 4b is supplied). That is, as described above, the predetermined recording signal set by the DC power supply DC1 is recorded on the track pattern TP while the second magnetic head 4b scans the magnetic tape 6 (see FIG. 3). (Illustrated in (b)).

When the rotary drum 5 is further rotated by a half turn, the ch2 pulse is supplied to the microcomputer 10 (a state in which the first magnetic head 4a scans the track pattern TP). The switch control signal (A) is output and the selector switch 12 is switched to the a side. The changeover switch 12 outputs, for example, a luminance signal supplied from a transmission line (not shown) in response to the switch control signal (A).

At the same time, the microcomputer 10 switches the switch control signal (C) to the "Low" state and outputs the signal supplied from the changeover switch 7 to the P side. At this time, since the magnetic tape 6 is kept in the stopped state, the first magnetic head 4a moves to the track pattern TP.
Will scan over.

However, at this time, the recording signal is recorded on the track pattern TP by the second magnetic head 4b as described above. However, as shown in FIG. 3, the angle of the gap G of the magnetic head is changed. Since the azimuth angle is also different, no signal is reproduced from the first magnetic head 4a. Then, the second magnetic head 4b having the same azimuth angle
The recorded signal is reproduced only when scans the track pattern TP.

By rotating the rotary drum 5 half a turn, ch
When 1 pulse is supplied to the microcomputer 10 (the state in which the second magnetic head 4b scans the track pattern TP), the microcomputer 10 sends the switch control signal (A) described above to a
On the side, the second magnetic head 4b moves to the track pattern while the switch control signal (C) is maintained at "Low".
Scan on TP (illustrated in Figure 3 (c)).

Then, the second magnetic head 4b obtains the above-mentioned recording signal as a reproduced FM signal, and supplies this to the preamplifier 8 via the P side of the changeover switch 3. The preamplifier 8 amplifies the supplied reproduction signal to a predetermined level and supplies it to the reproduction FM detector 9.

This reproduction FM detector 9 is equipped with the obtained reproduction F
The M signal is integrated and converted into a DC voltage signal, which is supplied to the microcomputer 10. The value of this DC voltage signal is obtained as a value proportional to the level of the reproduced FM signal. In the microcomputer 10, for example, a value of a DC voltage signal obtained from an ideal reproduced FM signal is stored in advance as an expected value in accordance with the type of magnetic tape, and the expected value and the DC voltage signal obtained this time are stored. The performance of the magnetic tape 6 can be determined by comparing the value with the value.

Since the performance of the magnetic tape 6 can be determined while the rotary drum 5 makes two revolutions, for example, if the rotary drum 5 is rotating at 30 revolutions / second in a home VTR, The time required for this performance determination is 2/3
It only takes 0 seconds (about 0.067 seconds).

However, it is not necessary to determine the performance of the magnetic tape 6 described above while the rotary drum 5 makes two revolutions. For example, in order to stably obtain the reproduced FM signal obtained, 5 is rotated a predetermined number of times, the DC voltage signal obtained each time the rotary drum 5 is rotated is stored in the memory 11, and the average value of these DC voltage signals is obtained to determine the performance of the magnetic tape 6. May be.

At this time as well, it is possible to erase the signal on the track pattern TP and record / reproduce the recording signal while the rotating drum 5 makes two revolutions.
Even if the rotary drum 5 is rotated 10 times, the performance of the magnetic tape 6 can be determined in 10/30 seconds (about 0.333 seconds).

Now, for example, the magnetic characteristics according to the performance of the above-mentioned magnetic tape 6 and the above-mentioned expected value are combined with the microcomputer.
If it is set to 10, it is possible to control the signal recording processing operation for performing signal recording according to the magnetic characteristics or the signal reproduction processing operation for performing signal reproduction by the performance determination of the magnetic tape 6 described above. . Therefore, a second embodiment of the present invention will be described next.

(Second Embodiment) A second embodiment of the present invention is a signal recording processing means (recording system signal processing circuit) for recording a signal on a track pattern TP formed on a magnetic tape 6.
In a magnetic recording / reproducing apparatus provided with 13) and a signal reproduction processing means (reproduction system signal processing circuit 14) for reproducing the signal recorded in the track pattern TP, a rotating drum is provided in a state where the magnetic tape 6 is stopped. Track pattern by passing a high frequency current through the first magnetic head 4a mounted on
Erase means for erasing the signal on TP (erase signal generator DC2,
FM modulator 1, recording amplifier 2) and erasing means DC2, 1, 2
Recording means for recording a predetermined signal having a plurality of gains set on the track pattern TP from which the signal has been erased by the second magnetic head 4b mounted on the rotary drum 5 having the magnetic head and the reverse azimuth (recording) Signal generator DC
1, FM modulator 1, recording amplifier 2) and recording means DC1,
The signal recorded by 1, 2 is immediately reproduced by the second magnetic head 4b, and the detecting means (preamplifier 8, reproduction FM detector) for detecting the signal having the maximum level among the reproduced predetermined signals. 9) and the output results of the detection means 8 and 9 to determine the signal recording / reproducing characteristics of the magnetic tape 6, and the recording system signal processing circuit 13 at the time of recording based on the determination result.
And a control means (microcomputer) 10 for controlling the signal processing circuit 14 and controlling the reproduction system signal processing circuit 14 at the time of reproduction.

As shown in FIG. 4, in the second embodiment of the present invention, a recording system signal processing circuit 13 and a reproduction system signal processing circuit 14 are added to the structure described in the first embodiment. At this time, although not described in detail here, the recording-system signal processing circuit 13 performs well-known signal processing in order to record the video signal and the audio signal supplied from the transmission line (not shown) on the magnetic tape 6 in a so-called home VTR. To give,
The reproduction system signal processing circuit 14 performs well-known signal processing having a configuration complementary to the above-mentioned signal recording processing means for demodulating a signal recorded on the magnetic tape 6 to obtain a video signal and an audio signal. Is. Although only the video signal processing will be described here, it is assumed that the audio signal is subjected to the audio signal processing according to the video signal processing.

The magnetic recording / reproducing apparatus records or reproduces a video signal on or from the magnetic tape 6 according to a recording instruction or a reproducing instruction inputted by the user. When the user inputs a recording instruction to record a video signal by an input means (not shown), the instruction information is supplied to the microcomputer 10, and the magnetic recording / reproducing apparatus is switched to the normal recording mode.

In this normal recording mode, as described in the first embodiment, the reproduced FM signal obtained by reproducing the recording signal recorded on the magnetic tape 6 is fed to the direct current through the preamplifier 8 and the reproduction FM detector 9. It is converted into a voltage signal and supplied to the microcomputer 10. The microcomputer 10 compares the DC voltage signal with the above-mentioned expected value to detect the magnetic tape 6
The performance is determined and the result is supplied to the memory 11.

The microcomputer 10 reads the performance determination result of the magnetic tape 6 stored in the memory 11 from the memory 11,
A recording control signal based on the performance discrimination result of the magnetic tape 6 is supplied to the recording system signal processing circuit 13. At this time, the microcomputer 10 supplies the switch control signal (A), the switch 12, the switch control signal (C), and the gain control signal (B) to the recording amplifier 2 and the recording amplifier 2, respectively. Here, this recording control signal is, for example, an information signal indicating a control amount such as recording level control for recording an optimum signal according to the above-described performance determination, gain control, emphasis control, etc. The control amount of the recording system signal processing circuit 13 according to the above-mentioned performance discrimination is set in advance.

When the recording control signal output from the microcomputer 10 is supplied to the recording system signal processing circuit 13, on the other hand, the video / audio signal supplied to the recording system signal processing circuit 13 from a transmission line (not shown) Recording level control, gain control, emphasis control, etc. are performed in accordance with the recording control signal.

The video signal output from the recording system signal processing circuit 13 is supplied to the changeover switch 12 and is supplied to the FM modulator 1 by the switch control signal (A). The FM-modulated signal in the FM modulator 1 is supplied to the recording amplifier 2, amplified to a recording level according to the recording control signal by the above-mentioned gain control signal (B), and supplied to the R side of the changeover switch 3 described above. To be done. The changeover switch 3 is operated by the switch control signal (C) described above via the head changeover switch 7 and the first and second magnetic heads 4 described above.
It is supplied to a and 4b.

The above-mentioned first and second magnetic heads 4a, 4b
Records the supplied video signal in a track pattern according to a predetermined recording operation. In this way, the video signal can be recorded based on the performance discrimination result of the magnetic tape 6 discriminated by the microcomputer 10. Therefore, the video signal which is always subjected to the recording signal processing according to the performance of the magnetic tape 6 can be recorded.
Can be recorded in.

Next, an explanation will be given of the case of performing the normal reproduction for reproducing the video signal recorded on the magnetic tape 6 as described above. For example, when the user inputs a reproduction instruction to reproduce the video signal recorded on the magnetic tape 6 by the input means (not shown), the instruction information is supplied to the microcomputer 10, and the magnetic recording / reproducing apparatus is switched to the normal reproduction mode. In this normal reproduction mode, the microcomputer 10 instructs the traveling drive of the magnetic tape 6 and the rotational drive of the rotary drum 5. In this way, the first and second magnetic heads described above have the magnetic tape 6
And a reproduction signal is supplied to the P side of the changeover switch 3 through the head changeover switch 7.

The microcomputer 10 outputs a control signal (C) and a reproduction control signal, which will be described later, together with an instruction to drive the magnetic tape 6 and a rotational drive of the rotary drum 5. At this time, the control signal (C) changes the output of the changeover switch 3 to P
Switch to the side. The reproduction signal output from the changeover switch 3 is supplied to the preamplifier 8, amplified by a predetermined amount in the preamplifier 8, and supplied to the reproduction system signal processing circuit 14 and the reproduction FM detector 9. The reproduction signal supplied to the reproduction FM detector 9 is integrated into the DC voltage signal as described above and supplied to the microcomputer 10. The microcomputer 10 determines the performance of the magnetic tape 6 by comparing this DC voltage signal with a preset expected value and supplies a playback control signal to the playback system signal processing circuit 14 based on this performance determination.

This reproduction control signal is, for example, an information signal for performing de-emphasis control for reproducing the signal reproduced in accordance with the above-mentioned performance discrimination with constant optimum characteristics, control for reproduction equalizing, and the like. The microcomputer 10 is preset with a control amount of the reproduction system signal processing circuit 14 according to the performance discrimination of the magnetic tape.

In this way, the reproduction system signal processing circuit 14 FM demodulates the reproduction signal supplied based on the reproduction control signal output from the microcomputer 10 and performs de-emphasis control, reproduction equalization, etc., to reproduce the reproduced video signal. Not output to a transmission path (for example, a display device such as a monitor). That is, since the video signal can be reproduced based on the performance discrimination result of the magnetic tape 6 discriminated by the microcomputer 10, the recorded video signal corresponding to the performance of the magnetic tape 6 is always discriminated according to the performance of the magnetic tape 6. It can be reproduced by the reproduction process.

Now, a third embodiment of the present magnetic recording / reproducing apparatus for making a more detailed performance determination with respect to the performance determination of the magnetic tape 6 will be described below.

(Third Embodiment) As shown in FIG. 5, in the third embodiment of the magnetic recording / reproducing apparatus, the DC power supply DC1 for supplying the recording signal in the second embodiment is replaced with a variable DC power supply DC3. Is. The DC power supply DC1 determines the frequency of the above-mentioned recording signal recorded to determine the performance of the magnetic tape 6, and the frequency of the recording signal can be changed by replacing it with the variable DC power supply DC3. You can For example, by supplying the reproduction signal reproduced for each recording signal whose frequency has been changed to the microcomputer 10, the frequency of the recording signal when the maximum output is obtained among the obtained reproduction signals is obtained. The performance of the magnetic tape 6 can be determined.

When the user inputs a recording instruction to record a video signal by an input means (not shown), the instruction information is supplied to the microcomputer 10 and the magnetic recording / reproducing apparatus is switched to the normal recording mode. In this normal recording mode,
As described above, the voltage signal output from the variable DC power supply DC3 is supplied to the R side of the changeover switch 3 as an erase signal via the FM modulator 1 and the recording amplifier 2. After erasing the signal on the track pattern TP by this erasing signal,
As described in the second embodiment, the changeover switch 3 outputs the voltage signal from the variable DC power supply DC3 by the switch control signal (C) output from the microcomputer 10.

At this time, the microcomputer 10 changes the level of the voltage signal output from the variable DC power supply DC3 by outputting the control signal (E). Then, as described above, the recording signal obtained from this voltage signal is used as the track pattern.
The reproduction signal recorded on the TP and reproduced is supplied to the microcomputer 10 through the preamplifier 8 and the reproduction FM detector 9.
The microcomputer 10 converts the reproduction signal converted into the DC voltage signal into
For example, it is supplied to the memory 11.

Next, the microcomputer 10 supplies the erase signals to the first and second magnetic heads 4a and 4b again by supplying the switch control signals (A) and (C) to the changeover switches 12 and 3, respectively. The level of the voltage signal output from the variable DC power supply DC3 is changed by the control signal (E).

Hereinafter, for example, erasing the signal on the track pattern TP, changing the frequency of the recording signal, recording the recording signal with the changed frequency, and reproducing the recorded signal are repeated a predetermined number of times. For example, it is assumed that the voltage value of the variable DC power supply DC3 corresponding to the frequency of the recording signal changed by the microcomputer 10 at this time is preset in the microcomputer 10.

In this way, the microcomputer 10 obtains the frequency of the recording signal when the maximum output is obtained among the DC voltage signals converted from the obtained reproduction signal, and by this, for example,
The magnetic characteristics of the magnetic tape 6 can be determined. That is, since the performance of the magnetic tape 6 can be determined, the microcomputer 10
The recording system signal processing circuit 13 can be controlled in the same manner as in the second embodiment described above according to the performance of the magnetic tape 6 determined by the above.

Further, as described above, the magnetic recording / reproducing apparatus of the present invention discriminates, for example, the magnetic tape 6 by discriminating the performance of the magnetic tape 6 during the normal recording or the normal reproduction in the normal recording mode and the normal reproduction mode, respectively. Even when the characteristics of the head change due to the wear of the head as the usage time accumulates, the recording system signal processing circuit 13 and the reproduction system signal processing circuit 14 can be controlled according to the performance discrimination of the magnetic tape 6. .

Incidentally, for example, by storing the performance determination result of the magnetic tape 6 in the memory 11, the performance stored in the memory 11 is maintained for a certain period until the characteristics of the head change due to wear of the magnetic head. Of course, the determination result may be read and used. That is, the performance determination result of the magnetic tape 6 performed once according to the wear stage of the magnetic head may be used. For example, the usage time of the magnetic head is continuously measured in a memory circuit not detailed here,
The performance determination result stored in the memory 11 may be updated by determining the wear stage of the magnetic head according to the usage time, and the performance determination of the magnetic tape 6 may be performed.

In the first and second embodiments, for example, the gain of the recording amplifier 2 may be changed by the gain control signal (B) according to the drum pulse supplied to the microcomputer 10. Of course.
That is, for example, by controlling the gain of the recording amplifier 2 to be gradually increased for each cycle of the drum pulse (1 cycle), the characteristics of the recording signal can be changed and reproduced without using the variable DC power supply DC3. The performance of the magnetic tape 6 may be determined by.

At this time, for example, in the recording amplifier 2, a recording amplifier for performing bias oscillation used in an audio circuit or the like may be applied so as to oscillate an erase signal instead of bias oscillation. Of course.

In the performance discrimination of the magnetic tape 6 described above, it goes without saying that the magnetic tape 6 may be erased, the signal may be recorded, and the recorded signal may be reproduced at different timings, as shown in FIG. is there. That is, as shown in FIG. 6A, a recording signal is recorded by a magnetic head (for example, a first magnetic head) that erases time by changing operation control of erasing, recording, and reproducing according to a drum pulse. You may replay this. Further, as shown in FIGS. 6B and 6C, it goes without saying that the magnetic tape 6 may be erased or the recording signal may be reproduced for a sufficient time. That is, in the former case, the signal components on the magnetic tape 6 can be sufficiently erased, and in the latter case, the average of the reproduced signals obtained is taken or the reproduced signals in a predetermined cycle are extracted. It is possible to obtain a stable reproduction signal. Therefore, it is possible to more accurately determine the performance of the magnetic tape 6 based on the reproduction signal thus obtained.

In the performance discrimination of the magnetic tape 6 described above, the first and second magnetic heads 4a and 4b are, for example, types of magnetic heads (for example, standard recording / reproducing heads, long-time recording / reproducing heads, etc.). Of course, the present invention is not limited to this, and can be effectively used in any type of magnetic head. Further, it goes without saying that the erasing, recording and reproducing operations described above may be alternately performed by various magnetic heads.

Of course, by discriminating the performance of the magnetic tape 6 described above, it is of course possible to record / reproduce video signals according to changes in signal recording / reproduction due to wear of the magnetic head or the like. By discriminating the performance of the magnetic tape 6 between the standard recording / reproducing head and the long-time recording / reproducing head, the optimum video signal corresponding to each of the standard recording / reproducing head and the long-term recording / reproducing head can be obtained. It goes without saying that recording / reproducing signal processing can be performed.

Incidentally, for example, the above-mentioned expected value is suitable for the type of the assumed magnetic tape 6 (for example, a standard type suitable for recording / reproducing repetitive signals, suitable for storing a signal once recorded with high quality). The type of the magnetic tape 6 may be instantly and concretely determined by presetting in accordance with the high grade type or the like) and extracting the closest one of the expected values of the DC voltage signal among the expected values. Of course.

Of course, this expected value may be set so that optimum recording and reproduction can always be performed according to the medium to which the video signal or the audio signal is supplied (for example, broadcasting digital from satellite broadcasting. A for audio signals, high definition, etc.
Expected value for recording / reproducing high-definition video signals from TV, external input video / audio signals, or other digital video / audio signals in an optimum state. That is, for example, when recording a broadcast digital audio signal from the satellite broadcast described above on a magnetic tape to be used, a signal recording process can be performed for the user to implement an optimum digital audio signal. Furthermore,
For example, it is of course possible to prevent the signal deterioration during dubbing by performing detail emphasis of the video signal in the signal recording processing operation, such as when the user performs dubbing to make a duplicate of the signal recorded on the magnetic tape. is there.

In the present magnetic recording / reproducing apparatus, the reproducing FM detector 9 described above has a structure for generating and outputting a DC signal by integrating the supplied reproducing FM signal. For example, the structure of the reproducing FM detector 9 is as follows. May be changed so that the envelope of the supplied reproduction FM signal is sequentially output to the microcomputer 10. For example, the following performance determination of the magnetic tape 6 may be performed.

That is, since the microcomputer 10 can directly detect the envelope of the obtained reproduced FM signal, for example, when recording a recording signal on the magnetic tape 6, recording is performed when the track pattern TP is scanned once. The performance of the magnetic tape 6 may be determined by continuously varying the recording level or frequency of the signal and comparing the level fluctuation of the reproduced FM signal reproduced by one-time recording with the above-mentioned expected value.

That is, by this deciding method, the signal erasing on the magnetic tape 6 and the recording / reproducing of the recording signal are performed once (twice for the rotating drum 5), and the microcomputer 10 continuously records the recording level or frequency. Since it is possible to obtain the level fluctuation of the reproduced FM signal which reproduces the recording signal changed to the above, the microcomputer 10 can determine the performance of the magnetic tape 6 from this level fluctuation and the above-mentioned expected value (the fastest). Performance determination of magnetic tape).

[0059]

As described above, according to the structure of the present invention as set forth in claim 1, the DC power source used for the erasing means and the DC power source used for the recording means are separately provided, so that the magnetic tape When performing performance discrimination, the signal component on the track pattern can be surely erased, and therefore a stable recording signal can be recorded on the track pattern and reproduced, so that the performance of the magnetic tape is always maintained. There is an effect that it is possible to obtain a reproduction signal according to the above.

As described above, according to the configuration of the present invention as set forth in claim 2, in addition to the above effects, it is possible to control the signal processing of the recording system signal processing circuit according to the performance discrimination of the magnetic tape. There is an effect that optimum signal recording can be performed according to the magnetic characteristics of the magnetic tape. Further, similarly, since the signal processing control of the reproduction system signal processing circuit according to the performance discrimination of the magnetic tape becomes possible, there is an effect that optimum signal reproduction can be performed with respect to the magnetic characteristics of the magnetic tape.

Further, even if the characteristics of the magnetic head itself change due to wear of the magnetic head, the performance of the magnetic tape can be determined according to the state of the magnetic head at that time. There is an effect that optimum signal recording or reproduction can be performed with respect to the magnetic characteristics of the tape.

Further, by comparing the preset expected value with the direct current voltage signal of the reproduction signal, there is an effect that accurate performance determination of the magnetic tape can be immediately performed. Further, by setting this reference value, for example, there is an effect that the optimum performance determination of the magnetic tape can be performed each time according to the situation selected by the user.

As described above, according to the structure of the present invention as set forth in claim 3, in addition to the above-mentioned effect, the erasing signal output by the erasing means can be obtained from an independent DC voltage signal, so that it is always stable. The track pattern can be erased. That is, there is an effect that the signal on the track pattern can be surely erased even if the magnetic head supplied with the erase signal scans the track pattern once. Further, since the recording signal output from the recording means can be obtained from an independent DC voltage signal, the track pattern can always be erased stably. That is, there is an effect that the signal can be surely recorded on the track pattern even if the magnetic head supplied with the recording signal scans the track pattern once.

Further, for example, since the recording signal output from the recording means can be obtained from an independent DC voltage signal,
Since it is possible to easily change the recording signal frequency to a desired value, it is possible to finely set the recording signal for accurately determining the performance of the magnetic tape.

As described above, according to the structure of the present invention described in claim 4, in addition to the above effects, the magnetic head for erasing the track pattern and the azimuth of the magnetic head for recording and reproducing the recording signal are Since they are different, it is possible to prevent the interference between the signal component used for erasing on the track pattern and the recording signal, and to improve the utilization efficiency of the first and second magnetic heads that are mounted on the rotating drum so as to face each other. The effect is that it can be increased. That is, for example, the recording signal can be recorded by the second magnetic heads having different azimuths after the first magnetic head erases,
There is an effect that the signal on the track pattern can be erased and the recording signal can be recorded while the rotating drum makes one rotation.

As described above, according to the fifth aspect of the present invention, in addition to the effects described above, signal erasure on the track pattern and recording signals are synchronized with the timing of the drum pulse output from the rotary drum. Since recording can be performed, there is an effect that the performance of the magnetic tape can be discriminated technically in the shortest time.

[Brief description of drawings]

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

FIG. 2 is a time chart for explaining the operation of the magnetic recording / reproducing apparatus according to the present invention.

FIG. 3 is a diagram for explaining a tape pattern relating to the operation of the magnetic recording / reproducing apparatus according to the present invention.

FIG. 4 is a block diagram for explaining a second embodiment of the magnetic recording / reproducing apparatus according to the present invention.

FIG. 5 is a block diagram for explaining a third embodiment of the magnetic recording / reproducing apparatus according to the present invention.

FIG. 6 is a time chart for explaining the operation of the magnetic recording / reproducing apparatus according to the present invention.

[Explanation of symbols]

 DC1,1, 2 recording means DC2,1,2 erasing means 4a first magnetic head 4b second magnetic head 6 magnetic tape (magnetic recording medium) 8,9 detecting means 11 memory 10 microcomputer (discriminating means / control means) 13 recording system signal processing circuit (signal recording processing means) 14 reproduction system signal processing circuit (signal reproduction processing means) TP track pattern

Claims (5)

[Claims] 1. A magnetic device comprising signal recording processing means for recording a signal on a recording track formed on a magnetic recording medium, and signal reproduction processing means for reproducing a signal recorded on the recording track. In the recording / reproducing apparatus, an erasing unit for erasing a signal on the recording track by applying a high-frequency current to a first magnetic head mounted on a rotating drum in a traveling stopped state of the magnetic recording medium; Recording means for recording a predetermined signal on a recording track from which a signal has been erased by a second magnetic head mounted on a rotary drum having an inverse azimuth with the first magnetic head; and a signal recorded by the recording means. Is immediately reproduced by the second magnetic head to detect the recorded signal, and the detection unit outputs the signal based on the output result of the detection unit. A magnetic recording / reproducing apparatus comprising: a discriminating unit for discriminating a signal recording / reproducing characteristic of a magnetic recording medium. 2. A magnetic device comprising signal recording processing means for recording a signal on a recording track formed on a magnetic recording medium, and signal reproduction processing means for reproducing a signal recorded on the recording track. In the recording / reproducing apparatus, an erasing unit for erasing a signal on the recording track by applying a high-frequency current to a first magnetic head mounted on a rotating drum in a traveling stopped state of the magnetic recording medium; A second signal in which a predetermined signal in which a plurality of gains are set is mounted on a rotary drum having an inverse azimuth and the magnetic head on a recording track from which the signal is erased.
Recording means for recording by the magnetic head, and detection for reproducing the signal recorded by the recording means immediately by the second magnetic head and detecting the signal having the maximum level among the reproduced predetermined signals. And a signal recording / reproducing characteristic of the magnetic recording medium from the output result of the detecting means, and based on the determination result, the signal recording processing means is controlled at the time of recording and the signal reproduction processing means is controlled at the time of reproduction. The control means controls the signal recording processing means at the time of recording by comparing a preset reference value with the detection result of the detection means, and the signal reproduction processing means at the time of reproduction. A magnetic recording / reproducing apparatus characterized by controlling the. 3. A magnetic device comprising signal recording processing means for recording a signal on a recording track formed on a magnetic recording medium, and signal reproduction processing means for reproducing a signal recorded on the recording track. In the recording / reproducing apparatus, an erasing unit for erasing a signal on the recording track by applying a high-frequency current to a first magnetic head mounted on a rotating drum in a traveling stopped state of the magnetic recording medium; A second signal in which a predetermined signal in which a plurality of gains are set is mounted on a rotary drum having an inverse azimuth and the magnetic head on a recording track from which the signal is erased.
Recording means for recording by the magnetic head, and detection for reproducing the signal recorded by the recording means immediately by the second magnetic head and detecting the signal having the maximum level among the reproduced predetermined signals. And a signal recording / reproducing characteristic of the magnetic recording medium from the output result of the detecting means, and based on the determination result, the signal recording processing means is controlled at the time of recording and the signal reproduction processing means is controlled at the time of reproduction. The magnetic recording / reproducing apparatus is characterized in that the erasing means and the recording means respectively output an erasing signal and a recording signal based on independent DC voltage signals. 4. A magnetic head for erasing a signal on at least the recording track and a magnetic head for recording and reproducing the predetermined signal on the recording track after the erasing are always in a reverse azimuth relationship. The magnetic recording / reproducing apparatus according to claim 1, wherein the magnetic recording / reproducing apparatus is a magnetic recording / reproducing apparatus. 5. The erasing means erases a signal on the recording track in synchronization with the timing at which the first or second magnetic head scans the magnetic recording medium, and the recording means erases the signal. 5. The magnetic recording medium according to claim 1, wherein a recording signal is recorded on the recording track in synchronism with a timing of scanning the magnetic recording medium by a magnetic head having an inverse azimuth relationship with the magnetic head used. Recording / playback device.