JPH0833975B2 - Magnetic recording / reproducing device - Google Patents

Description

The present invention relates to a magnetic recording / reproducing apparatus such as a rotary type digital audio tape recorder (hereinafter referred to as R-DAT).

(Prior Art) In recent years, there has been a remarkable reduction in the size of magnetic recording / reproducing apparatuses, and in particular, equipment that is carried around outdoors such as an R-DAT that has a simultaneous monitoring function that constantly monitors the recording state during recording. In this, downsizing, longer battery life, and lower prices are required. Similarly, the electric circuits that compose the same are required to have smaller scales, lower power consumption, and lower prices.

FIG. 11 is a block diagram showing an arrangement configuration of a conventional magnetic recording / reproducing apparatus during simultaneous monitoring.

In FIG. 11, 2a, 2b, 3a and 3b are heads in the rotary drum 1, 21 is a microphone amplifier, 22 is an A / D converter, 23 and 27 are signal processing LSIs, 24a and 24b are recording amplifiers, and 25a and 25b. Is a reproduction amplifier, 26 is an equalizer, 28 is a D / A converter, 29 is a line amplifier, 30 is an error counter, 31 is a phase synchronization circuit (hereinafter,
32) is an error indicator.

FIG. 12 shows the arrangement of the conventional rotary drum, magnetic head, and magnetic tape. In FIG. 12, 7 is a magnetic tape, 1 is a rotating drum that rotates counterclockwise, and 4a and 4b are tape traveling paths so that the magnetic tape 7 may be wound around the rotating drum 1 at an angle of ψ to travel. It is a travel guide post that is defined. Reference numerals 2a and 2b denote a pair of first magnetic heads having different azimuths, and are mounted inside the rotary drum 1 so as to face each other on the first plane by 180 degrees. Reference numerals 3a and 3b denote a pair of second magnetic heads having different azimuths, which are mounted 180 degrees on the second plane having a certain level difference from the first plane in the rotary drum 1. There is. The magnetic heads 2a and 3a have the same azimuth,
The main track rows 10a, 11a, 12a in FIG. 13 are traced, and the magnetic heads 2b and 3b have the same azimuth.
The main track rows 10b and 11b in FIG. 13 are traced. Here, the magnetic head 2a traces each main track of the main track rows 10a, 11a, 12a preceding the magnetic head 3a, and the magnetic head 2b precedes the magnetic head 3b and each main track of the track rows 10b, 11b. Shall be traced. Further, the winding angle ψ and the step between the first and second planes of the rotating drum 1 are set so that two or more of the magnetic heads 2a, 2b, 3a, 3b do not trace the main track row at the same time. , Head mounting angle (90 + θ)
Each degree is set. That is, as shown in the example of FIG. 13, when the head 3a reaches the end of the main track 11a, the head 2a comes to the start end of the main track 12a, so that the magnetic heads 2a and 3a, 2b and 3b respectively ( 90 + θ)
The winding angle ψ is set to be larger than that.

During simultaneous playback monitoring, the microphone input signal is amplified by the microphone amplifier 21, converted into a digital signal by the A / D converter 22, and becomes recording data for Ach and Bch by the recording signal processing LSI 23. The recording amplifiers 24a, 24b drive the preceding head 2a. , 2b and recorded on the tape 7. Here, the recorded data is reproduced by the follow-up heads 3a, 3b, the signal is amplified by the reproduction amplifiers 25a, 25b, the magnetic distortion is corrected by the equalizer 26, and the data clock is reproduced by the PLL 31 for reproduction. The signal processing LSI 27 performs error correction, the D / A converter 28 converts the error into an analog signal, and the analog signal is output through the line amplifier 29. In this way, simultaneous monitoring is realized. At this time, the error counter 30 counts the number of error corrections performed by the reproduction signal processing LSI 27 to recognize a reproduction error.

The signal processing LSI 27 displays the reproduction error occurrence rate on the A channel,
The B channel is counted independently, and when the head is clogged, the error display 32 indicates whether the A channel is clogged or the B channel is clogged.

(Problems to be Solved by the Invention) However, in the above-described conventional configuration, it is not possible to determine whether the preceding recording head is clogged or the follow-up reproducing head is clogged even when the A channel is displayed as clogged. Even when the follow-up head is clogged, it is necessary to interrupt the recording to check the head status of the device even though the preceding head can continue recording, and miss the chance of recording only once. Had a problem.

Further, there is a problem that it is necessary to re-analyze which head is clogged when performing maintenance after clogging.

Further, in order to realize the simultaneous monitoring function, two signal processing LSIs, a signal processing LSI for recording data by the preceding head and a signal processing LSI for reproducing data by the trailing head, and a trailing head are used. Two signal processing LSIs for reproducing data, a signal processing LSI and a reproduction equalizer,
Since it requires a PLL and a D / A converter, the circuit scale is large, which is a major obstacle to the downsizing of equipment, and it is difficult to reduce the price of equipment and save power.

The present invention solves the above problems, and the first invention is
As a simultaneous monitor, one signal processing LSI has a function to check which head is clogged and a function that, even if one of the follow-on heads is clogged, the other follow-on head can simultaneously monitor and continue recording. It is an object of the present invention to provide a magnetic recording / reproducing apparatus having a small electric circuit scale realized by the second aspect of the present invention, and the second invention is such that when the preceding head is clogged, the preceding head recording is switched to the following head recording, and recording is performed. It is an object of the present invention to provide a magnetic recording / reproducing device having a small electric circuit scale that realizes a continuous function.

(Means for Solving the Problems) In order to achieve the above-mentioned object, the first invention is
A signal processing unit that processes an input signal as a recording signal and generates a signal so as to record a sync signal and a pilot signal in a predetermined area of a track on a tape at the time of recording, and a recording signal is given from the signal processing unit, A recording head mounted on a rotating drum for helically scanning the magnetic tape and a recording head preceding the track row on the magnetic tape are traced alternately and independently after recording. A follow-up reproducing head having a track width wider than a recording track pattern width on a magnetic tape, for reading a signal recorded on the track and reproducing a part of an adjacent track by overlapping. At the time of reproduction by the follow-up reproduction head, a sync signal detector for detecting the sync signal of the reproduction track and an adjacent A pilot signal detector that detects the crosstalk component of the track pilot signal, and an error detector that detects which head is clogged based on the combination of the detection signals by the sync signal detector and the pilot signal detector. I have. Further, an error indicator is used to indicate which head is clogged by the error detector. Further, by the error detector, when the error is due to the clogging of the leading head, the trailing head, the clogging of the respective A heads, and the B heads, time or It uses a warning signal generator that changes the frequency and outputs a warning signal.

The second invention is in addition to each means shown in the first invention,
A memory that sequentially stores the recording signals obtained from the signal processing unit and outputs data when the reproducing head reproduces the recorded track; and a switch that selects the input of the recording amplifier between a signal processing output and a memory output. , A switch for selecting the output of the recording amplifier between the preceding head and the trailing head, a switch for selecting whether to connect the input of the reproducing amplifier to the trailing head, and when the preceding head is not clogged, Set the recording state while the preceding head is traveling on the track on the tape, and, if the preceding head is clogged, the recording state while the following head is traveling on the track on the tape. If the recording amplifier controller that controls the recording amplifier and the preceding recording head are clogged, the memory output is input to the recording amplifier. And-option, choose the rear chase head output of the recording amplifier, as cut loose from the rear chase head input reproducing amplifier, and has a switch switching circuit for controlling the switch. Further, the error detector uses an error indicator for displaying which head is clogged, whether the recording is performed by the preceding head or the following head, and whether simultaneous monitoring is possible. It is a thing. Further, by the error detector, which head is clogged, whether the recording is performed by the preceding head or the following head,
It uses a warning signal generator that outputs a warning signal by changing whether or not simultaneous monitoring is possible with respect to time or frequency.

(Operation) Therefore, according to the present invention, when the input signals are simultaneously monitored by the configuration of the first invention, the sync signal from the reproduction head output and the crosstalk component of the pilot signal of the adjacent track are detected. Based on the combination of the detection signals, a warning signal indicating which head has been clogged is issued to monitor the recording state.

Further, according to the second aspect of the invention, when the preceding head is clogged, the preceding head recording is switched to the following head recording, and the recording signal is delayed in the memory to ensure track continuity. .

(Embodiment) FIG. 1 is a block diagram showing a connection structure of a magnetic recording / reproducing apparatus according to an embodiment of the first invention during simultaneous monitoring, and FIG. 2 is a schematic diagram of a tracking signal (ATF) in an R-DAT. , FIG. 3 is a track schematic diagram and a sync signal when the follow-up reproducing head 3a reproduces the ATF2 of the 11a track in FIG. 1,
Timing chart of sampling pulse and pilot signal, FIG. 4 is a timing chart of recording, reproduction, sync signal detection, pilot signal sampling timing, pilot signal detection, and FIG. 5 is a follow-up reproducing head when the preceding recording head 2b is clogged. ATF with 3a and 11a tracks
Track outline diagram when playing 2 and timing chart of sync signal, sampling pulse, pilot signal,
FIG. 6 shows recording when the preceding recording head 2b is clogged,
Playback, sync signal detection, pilot signal sampling timing, pilot signal detection timing chart,
FIG. 7 is a track schematic diagram when the follow-up playback head 3a plays ATF2 of 11a track when the follow-up playback head 3a is clogged and a timing chart of sync signal, sampling pulse, pilot signal, and FIG. 8 is follow-up playback. 6 is a timing chart of recording, reproduction, sync signal detection, pilot signal detection sampling timing, and pilot signal detection when the head 3a is clogged.

In FIG. 1, the magnetic recording / reproducing apparatus has a microphone amplifier 21 for amplifying a microphone input signal, and its output is
It is converted into a digital signal by the A / D converter 22, and becomes recording data of Ach and Bch by the recording signal processing LSI 23. This data is sent from the recording amplifiers 24a, 14b to the preceding heads 2a, 2b and recorded on the tape as in the conventional example described above. The data recorded on the tape 7 is reproduced by the follow-up heads 3a, 3b, and its signal is reproduced by the reproduction amplifiers 25a, 2b.
It is amplified by 5b and output.

From the amplified output from the Ach reproduction amplifier 25a, a sync signal f2 is extracted by a bandpass filter (BPF) 33, punched out by a comparator (COMP) 34, and DSA is output. This is detected by the sync signal detector 35. At the same time, DSA
Is sent to the sampling pulse generator 36 and outputs the sampling pulse SPA. The pilot signal is extracted by the bandpass filter (BPF) 37, punched out by the comparator (COMP) 38, and output as DPB. The pilot signal detector 39 detects DPB at the timing of SPA.

Similarly, the amplified output from the Bch reproduction amplifier 25b is also extracted with the sync signal f3 by the hand pass filter (BPF) 40,
It is punched out by the comparator (COMP) 41 and outputs DSB. This is detected by the sync signal detector 42. At this time, the DSB is simultaneously sent to the sampling pulse generator 43 and outputs the sampling pulse SPB. The pilot signal is extracted by the bandpass filter (BPF) 44, punched out by the comparator (COMP) 45, and output as DPA. The pilot signal detector 46 detects the timing DPA of SPB.

The detection results of these signals DSA, SAB, DPA, DPB are sent to the error detector 47, which is combined to determine which head is clogged, and the error display 48 receives and displays the error information.

The error information is also sent to the warning signal generator 50, and the time is calculated depending on whether the leading head is clogged, the trailing head is clogged, the A head is clogged, or the B head is clogged. A warning signal by changing the target or frequency. For example, if none of the heads are clogged,
No warning signal is generated. When one of the following playback heads is clogged, a warning signal of a certain audible frequency f ₀ indicating that the other head can be simultaneously monitored is generated. When the preceding recording head is clogged, a warning signal of a certain audible frequency f ₁ is generated, which indicates that it is impossible to continue recording. In this way, the warning signal may be divided in frequency, or instead of f ₀ , it may be divided short in a certain audible frequency, and instead of f ₁ , it may be divided in time so that it beeps long at the same frequency. May be separated.

Further, the signal input to the microphone is output from the microphone amplifier 21 through the mixing amplifier 49, the line amplifier 29, and the line output. The warning signal generator 50 outputs a warning signal by changing it with time or frequency and outputs the warning signal.
At 49, the warning sound is superimposed on the monitor sound.

Next, the judgment method of the error detector will be described. FIG. 3 shows a schematic view of the track and head when the follow-up reproducing head 3a reproduces the ATF2 of track 11a in FIG. The follow-up reproducing head 3a has a wider track width than the recording track 11a on the tape, and reproduces the data on 11a by azimuth recording and the pilot signal of the adjacent track.
First, by detecting the DSA by the sync signal f ₂ of the track 11a, it can be confirmed that the preceding recording head 2a recorded the track 11a without clogging and that the follow-up reproducing head 3a reproduced the track 11a without clogging. . Also,
By detecting the pilot signal (DPB) of the track 11b with the sampling pulse (SPA) at that time, the preceding recording head 2b recorded the track 11b without clogging, and the follow-up reproducing head 3b reproduced without clogging. I can confirm.

FIG. 4 shows a timing chart of recording, reproduction, sync signal detection, pilot signal sampling timing, and pilot signal detection.

t is a time domain division as each head traces the main track. Reference numerals 10a, 10b, 11a, 11b and 12a are the tracks shown in FIG. For example, the DSA detection at t _5, it is not preceded recording head 2a is clogged at time t _2, you can see that not playing head 3a clogging afterward at time t _5, the detection of the DPB, time t ₄ by preceding recording heads 2b is not clogged, it can be confirmed that the post-chase reproducing head 3a is not clogged at time t _5. Also,
By detecting the DSB at time t ₃ , the preceding recording head 2b at time t ₀
Is not clogged, the follow-up playback head at time t ₃
3b It can be confirmed that it is not clogged, and by DPA detection, it is possible to confirm that the preceding recording head 2a is not clogged at time t ₂ and that the trailing playback head 3b is not clogged at time t _3. .

In this way, by detecting DSA, SAB, DPA, and DPB, it is possible to confirm the clogging state of each head, thereby realizing simultaneous monitoring.

Next, a method of determining the case of clogging will be described. Figure 5 shows a case where the preceding recording head 2b is clogged at time t _4. Since the preceding recording head 2b does not record the track 11b, the follow-up reproducing head 3a cannot detect the DPB. When shown in FIG. 6, the detection of DSA in time t _5, it can be confirmed that the preceding recording head 2a at time t ₂ may not clogged, which not playing head 3a clogging afterward at time t _5. However, the inability to DPB detection, post-chase reproducing head 3a so not clogged, it can be confirmed that the preceding recording head 2b is clogged at time t _4.

FIG. 7 shows a case where the follow-up reproducing head 3b is clogged at time t ₅ . Since the follow-up playback head 3b cannot be played back,
The sync signal f ₂ of the recorded track 11a is not reproduced, DSA cannot be created, and the pilot signal DPB cannot be detected either. As shown in FIG. 8, by detecting the DPA at time t ₃ , it was confirmed that the preceding recording head 2a recorded the track 11a without clogging at the time t ₂ , and then the track 11a was replayed at the time t _5. Since the head 3a cannot detect the DSA, it can be confirmed that the follow-up reproduction head 3a is clogged.

In this case, by detecting the DSB at time t ₇ , it can be confirmed that the preceding recording head 2b is not clogged at time t ₄ , and the DP
By the detection of A, it is possible that the preceding recording head 2a at time t ₆ can be sure that it is not clogged, continue to simultaneously monitor the clogging of the preceding recording head in the only post-chase playback head 3b.

As such a simultaneous monitor, it is possible to reliably confirm the error occurrence of head clogging.

It should be noted that the magnetic heads 2a and 3a have the same azimuth and trace the main track rows 10a, 11a, 12a in FIG. 12, and the magnetic heads 2b and 3b have the same azimuth. The main track rows 10b and 11b are traced. Here, the magnetic head 2a traces each main track of the main track rows 10a, 11a, 12a prior to the magnetic head 3a, and the magnetic head 2b precedes the magnetic head 3b and each main track of the trace rows 10b, 11b. Shall be traced. Further, as shown in FIG. 11, the winding angle ψ and the first position of the rotary drum 1 are set so that two or more heads of the magnetic heads 2a, 2b, 3a, 3b do not simultaneously trace the main track row. And a step between the second planes and a head mounting angle (90 + θ) degrees are set. That is, as shown in the example of FIG. 13, when the head 3a reaches the end of the main track 11a, the head 2a is located at the start end of the main track 12a.
And 3b each have an angle of (90 + θ) degrees, and the winding angle ψ is set to be larger than that. The relationship between the arrangement of the rotary drum, magnetic head, and magnetic tape and the track pattern on the magnetic tape is the same as in the conventional example.
This is as shown in Figs. 11 and 12.

In this embodiment, R-DAT is used for playback tracking A.
This is an example of using the sync signal and the pilot signal of the TF signal, but the present invention is not limited to these and can be realized by separately recording and reproducing the sync signal and the pilot signal at a predetermined track position.

In the configuration of the first invention, the preceding recording head records the recording data on the magnetic tape, and the follow-up reproducing head detects the crosstalk components of the sync signal of the reproducing track and the pilot signal of the adjacent track, thereby When an error that cannot be detected occurs, it is equipped with a means to display which head is clogged with an error, or to change the time or frequency to superimpose a warning signal on the line output. A person who operates the device can be surely recognized whether the head is clogged, the preceding recording head is operating without clogging, and recording continues even if one of the following playback heads is clogged. This eliminates the problem of missing a recording opportunity that is only once.

Further, when performing maintenance after clogging, there is no problem that it is necessary to re-analyze which head is clogged.

Further, these can be easily configured by one recording signal processing LSI, a general-purpose CMOS gate for reproduction and a signal generator. Particularly, in the case of R-DAT, as shown in the embodiment, the sync signal and pilot signal of the ATF signal for reproduction tracking can be used, and it is not necessary to recreate the sync and pilot signals at the time of recording. The reproduction tracking circuit can be shared for the detection of the sync and pilot signals at the time, and a new detection circuit is not required. Therefore, unlike the conventional case, two signal processing LSIs are required, the circuit scale is large, which is a great obstacle to downsizing of the device, and it is difficult to reduce the cost of the device and save power.

Next, an embodiment of the second invention will be described with reference to the drawings. FIG. 9 is a block diagram showing the connection structure of the magnetic recording / reproducing apparatus in the second embodiment at the time of simultaneous monitoring, and FIG. 10 is recording / reproducing when the preceding recording head 2b is clogged, and data transfer to / from the memory. 3 is a timing chart of switch switching, recording amplifier switching, sync signal detection, pilot signal sampling timing, and pilot signal detection.

In FIG. 9, the magnetic recording / reproducing apparatus has a microphone amplifier 21 for amplifying a microphone input signal, and its output is
The signals are converted into digital signals by the A / D converter 22, converted into recording signals of Ach and Bch by the recording signal processing LSI 23, and sent to the X terminals of the switches (hereinafter referred to as SW) 5 and SW6. At the same time, it is sent to the memories 51a and 51b. This memory sequentially stores recording signals and outputs them with a certain time delay.
That is, a certain recording signal is stored at the same time as the preceding head records, and the recording signal is output when the follow-up reproducing head reproduces the track. The recording signal output from the memory is sent to the Y terminals of SW5 and SW6.

This recording signal is sent from the common C terminals of SW5 and SW6 to the recording amplifiers 24a and 24b. The output of the recording amplifier enters the common C terminals of SW1 and SW2, is sent from the X terminal to the preceding heads 2a and 2b, and is recorded on the tape 7.

The Y terminals of SW1 and SW2 are connected to the follow-up reproducing heads 3a and 3b.

The data recorded on the tape 7 is recorded by the follow-up reproducing head 3
The signal is reproduced by a and 3b, and the signal is sent to the X terminals of SW3 and SW4, sent from the common C terminal to the reproduction amplifiers 25a and 25b, amplified and output. The SW3 and SW4 Y terminals are grounded so that noise will not enter and error detection will not malfunction if the playback amplifier input is not connected to the follow-up playback head.

The processing of the amplified output from the reproduction amplifiers 25a and 25b is the same as that of the first invention, and the error information indicating which head is clogged is output from the error detector 47.

If the preceding heads 2a and 2b are not clogged by the error information due to the error information, the recording amplifier controller 52 sets the preceding heads 2a and 2b so that the preceding heads 2a and 2b are in the recording state while traveling on the track on the tape. If even one of them is clogged, the recording amplifiers 24a and 24b are controlled so as to be in the recording state while the follow-up head travels the track on the tape. In addition, the switch switching circuit 53 causes the contacts of SW1, SW2, SW3, SW4, SW5, and SW6 to switch the head 2 according to the error information.
If a and 2b are not clogged, set so that the common C terminal and X terminal are connected. If even one of the preceding heads is clogged, switch so that the common C terminal and Y terminal are connected. do.

FIG. 10 is a timing chart of recording, reproduction, memory data input / output, switch switching, recording amplifier switching, sync signal detection, pilot signal sampling timing, pilot signal detection when the preceding recording head 2b is clogged on the track 11b. Show.

At time t ₂ , the preceding head 2a records the track 11a.
Next, at time t ₄ , the preceding head 2b becomes clogged and the track
Do not record 11b.

In the clogging detection, as shown in FIGS. 5 and 6 of the first invention, the error detector detects and determines the presence or absence of the sync signal DSA and the pilot signal DPB at time t ₅ , and the preceding head 2b detects the presence of the sync signal DSA and the pilot signal DPB. Make sure it is clogged.

This error information causes the switch switching circuit 53 to operate at time t ₆
After that, control so that the common C terminal is connected to the Y terminal,
The data is output from the recording amplifier memory, the recording data is sent to the trailing head, and the input of the reproducing amplifier is cut off from the trailing head.

Recording amplifier controller 52, the time t ₆ after the rear chase head is controlled to while traveling the tracks on the tape, the recording amplifier becomes recording state.

As a result, at time t ₅ , the follow-up head 3a moves to the track 11a.
And the follow-up head 3b records the track 11b at time t ₇ , and the tracks on the tape can be made continuous without any loss. Time t ₇ or later, it can be done to continue the record in the post-chase head.

In the configuration of the second aspect of the invention, a recording data is stored at the same time as the preceding head records, and a memory for outputting the data when the following head is reproduced by the following head is provided, and the following data is recorded when the preceding recording head is clogged. It is equipped with a switch means that switches the playback head from playback to recording and switches to the follow-up head recording, so that the follow-up playback head is operating without clogging and recording can be continued even if the preceding recording head is clogged. You can do it, and you won't have to worry about missing a recording opportunity once.

Further, like the first invention, they can be easily configured by one signal processing LSI for recording, a general-purpose CMOS gate for reproduction and a signal generator. Especially R-DA
In the case of T, as shown in the embodiment, it is possible to use the sync signal and the pilot signal of the ATF signal for reproduction tracking, and it is not necessary to recreate the sync at the time of recording, the pilot signal, the sync at the time of reproduction, The reproduction tracking circuit can be shared for the detection of the pilot signal, and a new detection circuit is not required. Therefore, unlike the conventional case, two signal processing LSIs are required, the circuit scale is large, which is a great obstacle to downsizing of the device, and it is difficult to reduce the cost of the device and save power.

(Effects of the Invention) As is apparent from the above, the present invention has a configuration in which only one signal processing LSI is provided, and the crosstalk between the sync signal of the reproduction track and the pilot signal of the adjacent track in the follow-up reproduction head. By detecting the components, the recording state can be monitored at the same time, and it can be surely recognized which head is clogged. Further, even if one of the follow-up heads is clogged, the other follow-up head can continue the simultaneous monitoring. Therefore, by using this circuit configuration, it is possible to provide a magnetic recording / reproducing apparatus which is small in size, has a long battery life, and can be simultaneously monitored at a low price, and has a large practical effect.

The second invention, in addition to the effects of the first invention,
It has a memory that stores the recorded data at the same time as the preceding head records it, and outputs that data when the following playback head plays back that track.When the preceding recording head is clogged, the following playback head switches from playback to recording. By recording the memory output with the follow-up head,
Even if the follow-up reproducing head is operating without clogging and the preceding recording head is clogging, recording can be continued. Therefore, by using this circuit configuration, it is possible to provide a magnetic recording / reproducing apparatus that is small in size, has a long battery life, is inexpensive, and is capable of performing high-performance simultaneous monitoring, and has a large practical effect.

[Brief description of drawings]

FIG. 1 is a block diagram showing a connection structure of a magnetic recording / reproducing apparatus according to an embodiment of the first invention during simultaneous monitoring, and FIG. 2 is a schematic diagram of a tracking signal (ATF) in R-DAT,
FIG. 3 shows that the follow-up reproducing head 3a has an A on track 11a in FIG.
Schematic diagram of track when reproducing TF2 and timing chart of sync signal, sampling pulse, pilot signal, Fig. 4 is timing chart of recording, reproduction, sync signal detection, pilot signal sampling timing, pilot signal detection, Fig. 5 When the preceding recording head 2b is clogged, the follow-up playback head 3a is the ATF2 of track 11a.
Schematic of the track and the timing chart of the sync signal, sampling pulse, and pilot signal when playing back the data. Figure 6 shows the recording, playback, sync signal detection, pilot signal sampling timing, and pilot signal when the preceding recording head 2b is clogged. 7 is a timing chart of detection, FIG. 7 is a track schematic diagram when the back-end playback head 3a plays back the ATF2 of 11a track when the back-end playback head 3a is clogged, and a timing chart of sync signal, sampling pulse, pilot signal, FIG. 8 is a timing chart of recording, reproduction, sync signal detection, pilot signal sampling timing, pilot signal detection when the follow-up reproducing head 3a is clogged, and FIG. 9 is magnetic recording in one embodiment of the second invention. Block diagram showing the connection configuration for simultaneous playback device monitoring Figure 10 prior recording heads 2b
Recording / playback, memory data loading / unloading, switch switching, recording amplifier switching, sync signal detection, pilot signal sampling timing,
Timing chart of pilot signal detection, Fig. 11 is a block diagram showing the configuration of a conventional magnetic recording / reproducing apparatus, Fig. 12 is a layout diagram of a conventional circuit drum, a magnetic head, and a magnetic tape, and Fig. 13 is a conventional magnetic tape. It is a schematic diagram of an upper track pattern. 1 ... rotating drum, 2a ... leading A head, 2b ... leading B head, 3a ... trailing A head, 3b ... trailing B
Heads, 4a, 4b ... Running guide columns, 7 ... Tape, 10,11,1
2 ... Main track, 21 ... Microphone amplifier, 22 ... A / D converter, 23, 27 ... Signal processing LSI, 24a, 24b ... Recording amplifier, 25
a, 25b ... reproduction amplifier, 26 ... equalizer, 28 ... D / A converter,
29 ... Line amplifier, 30 ... Error counter, 31 ... Phase synchronization circuit (PLL), 32, 48 ... Error indicator, 33, 37, 40, 44 ... BP
F, 34, 38, 41, 45 ... Comparator (COMP), 35, 42 ... Sync signal detector, 36, 43 ... Sampling pulse generator, 39,
46 ... Pilot signal detector, 47 ... Error detector, 49 ... Mixing amplifier, 50 ... Warning signal generator, 51a, 51b ... Memory, 52 ... Recording amplifier controller, 53 ... Switch switching circuit.

Claims (6)

[Claims] 1. A signal processing section for processing an input signal as a recording signal and generating a signal for recording a sync signal and a pilot signal in a predetermined area of a track on a tape at the time of recording, and recording by the signal processing section. A recording head, which is provided with a signal and is attached to a rotating drum to helically scan the magnetic tape, and a recording head preceding the track row on the magnetic tape, alternately and independently after recording. Has a track width wider than the recording track pattern width on the magnetic tape in order to read signals recorded on the tracks and reproduce by overlapping a part of the adjacent tracks. A follow-up playback head and a sync signal detection for detecting a sync signal of a playback track during playback by the follow-up playback head. Signal detector, a pilot signal detector for detecting crosstalk components of pilot signals of adjacent tracks, and which head is clogged based on a combination of the detection signals by the sync signal detector and the pilot signal detector. A magnetic recording / reproducing apparatus comprising an error detector. 2. The magnetic recording / reproducing apparatus according to claim 1, further comprising an error indicator for indicating which head is clogged by the error detector. 3. The error detector outputs a warning signal by changing the time or frequency depending on whether the error is in the leading head, trailing head, or each head. The magnetic recording / reproducing apparatus according to claim 1, wherein a warning signal generator is used. 4. A signal processing unit for processing an input signal as a recording signal and generating a signal for recording a sync signal and a pilot signal in a predetermined area of a track on a tape at the time of recording, and recording by the signal processing unit. A recording head, which is provided with a signal and is attached to a rotating drum to helically scan the magnetic tape, and a recording head preceding the track row on the magnetic tape, alternately and independently after recording. Has a track width wider than the recording track pattern width on the magnetic tape in order to read signals recorded on the tracks and reproduce by overlapping a part of the adjacent tracks. A follow-up playback head and a sync signal detection for detecting a sync signal of a playback track during playback by the follow-up playback head. Signal detector, a pilot signal detector for detecting crosstalk components of pilot signals of adjacent tracks, and which head is clogged based on a combination of the detection signals by the sync signal detector and the pilot signal detector. An error detector, a memory that sequentially stores the recording signals obtained from the signal processing unit, and outputs the recording signals when the reproducing head reproduces the recorded track, and a signal processing output and a memory for the input of the recording amplifier. A switch for selecting the output, a switch for selecting the output of the recording amplifier for the preceding head and the follow-on head, a switch for selecting whether to connect the input of the reproducing amplifier to the follow-on head, and the preceding head If it is not jammed, while the preceding head is traveling the track on the tape, the If the head is clogged, while the follow-up head is traveling on the track on the tape, the recording amplifier controller that controls the recording amplifier and the input of the recording amplifier when the preceding recording head is not clogged in the recording state When the direct output from the signal processing LSI is connected to, the output of the recording amplifier is connected to the preceding head, and the input of the reproducing amplifier is connected to the follow-up head, the switch is controlled and the preceding recording head is clogged. , A memory switch is connected to the input of the recording amplifier, the output of the recording amplifier is connected to the follow-up head, and the input of the reproduction amplifier is cut off from the follow-up head. Characteristic magnetic recording / reproducing device. 5. The error detector detects which head is clogged and whether recording is performed by the preceding head.
5. The magnetic recording / reproducing apparatus according to claim 4, further comprising an error indicator for indicating whether the follow-up head is used and whether simultaneous monitoring is possible. 6. The error detector detects which head is clogged and whether recording is performed by the preceding head.
5. The magnetic recording according to claim 4, wherein a warning signal generator is used, which outputs a warning signal by changing temporally or frequencyally whether it is performed by a follow-up head and whether simultaneous monitoring is possible. Playback device.