JPH0259535B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION TECHNICAL FIELD The present invention relates to a tracking signal detection device for a rotating magnetic head type magnetic recording/reproducing device, and more particularly to a tracking signal detection device for a rotating magnetic head type digital tape recorder.

Prior Art In recent years, a rotating magnetic head type digital audio tape recorder (hereinafter referred to as ``DAT'') has been developed as a rotating magnetic head type magnetic recording and reproducing device, which digitizes audio signals and records them on a magnetic tape using a rotating magnetic head. has been done.

By the way, this kind of DAT is different from other rotating magnetic head type magnetic recording and reproducing devices.
As with VTRs, data recorders, etc., so-called tracking deviation occurs in which the magnetic head does not scan the recording track accurately due to the elongation of the magnetic tape or dimensional errors between the DATs.

Therefore, various tracking signal detection devices have been proposed in the past in order to prevent such tracking deviations in DAT.

As shown in FIGS. 1 to 3, such conventional tracking signal detection devices record a first pilot signal f ₁ having a different frequency in the pilot signal recording area of each track on a magnetic tape.
(shown with diagonal lines in the figure) and the second pilot signal f ₂ (shown with horizontal stripes in the figure) are recorded in a predetermined order.

Then, with the time when a predetermined reproduction pilot signal of a regular track (track to be traced) is detected during reproduction as a reference timing S, a first sample is used to sample leakage signals of predetermined reproduction pilot signals of both adjacent tracks of the regular track. , the second timings t ₁ and t ₂ are determined, and the determined first and second timings t 1 and t 2 are determined.
At second timings t1 _{and t2} , predetermined reproduction pilot signals of both adjacent tracks are sampled and held, and the difference between these held signals is detected to detect the amount and direction of tracking deviation. Note that in FIGS. 1 to 3, P indicates the direction of movement of the magnetic head.

That is, in the case shown in FIG. 1, for tracks A (A ₁ to A _o ) of each track, the first pilot signal f ₁ , the blank, and the second pilot signal f ₂ are recorded in this order. Regarding track B (B ₁ to _{B o} ),
The second pilot signal f ₂ , a blank, and the first pilot signal f ₁ are recorded in this order.

Note that the recording length l ₁ of the first pilot signal f ₁ , the recording length l ₂ of the second pilot signal f ₂ , the blank recording length l ₃ of track A and the blank recording length of track B
The relationship with l ₃ B is l ₁ :l ₂ :l ₃ A:l ₃ B=2:1:1:2.

For example, when tracing track A ₂ in FIG. 1, the reference point is the time when the second pilot signal f ₂ of track A ₂ is detected, or the time when the first pilot signal f ₁ of track A 2 is detected. Sample timings t ₁ and t ₂ are determined as timing S, and the leakage signals of the first pilot signals f ₁ and f ₁ of adjacent tracks B ₁ and B ₂ are sampled and held, and the respective leakage amounts are determined. Detect the difference between

In addition, in the case shown in FIG. 2, for track A of each track, the first pilot signal is
f ₁ , the second pilot signal f ₂ , and the first pilot signal f ₁ , and for track B, the second pilot signal f ₂ and the first pilot signal
f ₁ and the second pilot signal f ₂ are recorded in this order.

Note that the recording length l ₁ of the first pilot signal f ₁ and the recording length l ₂ A of the second pilot signal f ₂ of track A are
and the recording length l ₂ B of the second pilot signal f ₂ of track B have a relationship of l ₁ :l ₂ A:2lB=1:2:1.5.

For example, when tracing track _A2 in FIG. ₂ , sample timings _t1 and _t2 are determined using the reference timing S as the point in time when the first pilot signal _f1 of track A2 is detected. The leakage signals of the first pilot signals _f1 and _f1 of adjacent tracks _B1 and _B2 are sampled and held, and the difference in the amount of leakage is detected.

Furthermore, in the case shown in FIG. 3, for track A of each track, the first pilot signal is
The signals are recorded in the order of f ₁ , blank, and first pilot signal f ₁ ' (f ₁ = f ₁ ', but they are distinguished for the sake of explanation). For track B, the first pilot signal f ₁ , blank,
The signals are recorded in the order of the second pilot signal _f2 .

Note that the recording length l ₁ of the first pilot signal f ₁ , the recording length l ₁ ' of the first pilot signal f ₁ ', the recording length l ₃ of the second pilot signal f ₂ and the blank space are l ₁ :l. ₁ ′:l ₂ :
The relationship is l ₃ =1:2:2.

For example, when tracing track A ₂ , sample timings t ₁ and t 2 are determined using the point in time when the first pilot signal f _{1 of track A 2} is detected as a reference timing S, and sample timings t ₁ and t ₂ are determined to trace the adjacent track B ₁ . , B ₂ A, B second pilot signal
The leakage signals of f ₂ and f ₂ are sampled and held, and the difference between the respective leakage amounts is detected.

However, in each of these tracking signal detection devices, since the arrangement order of the first pilot signal _f1 and the second pilot signal _f2 is different between track A and track B, it is difficult to distinguish between track A and track B during recording. In this case, the output order of the first pilot signal _f1 and the second pilot signal _f2 must be switched, which causes the disadvantage that the configuration of the pilot signal recording system becomes complicated.

Further, sample timings t 1 _and t ₂ are determined using the time point at which the first pilot signal f ₁ or the second pilot signal f ₂ is detected as a reference timing, and
Since the sample is held at the sample timings t ₁ and t ₂ , if the reference timing is detected due to disturbance etc., the sample timing is changed accordingly.
Since t ₁ and t ₂ are determined and sample hold is automatically performed, there is a risk of erroneous detection at unnecessary portions.

Furthermore, in the case shown in FIG. 1, when the recording length of the second pilot signal _f2 is set to "1",
The maximum length l of the signal recording area is l = 5, and even in the case shown in Fig. 3, if the recording length of the first pilot signal _f1 is set to "1", The length l becomes l=5.

On the other hand, in the case shown in Figure 2,
When the recording length of the first pilot signal _f1 is set to "1", the maximum length l of the pilot signal recording area is l=
It becomes 4.

In other words, what is shown in Figures 1 and 3 is
Assuming that the maximum length of the pilot signal recording area is longer than that shown in the figure and the track length is the same,
There is a disadvantage that the amount of information that can be written in the main data is reduced.

In this regard, what is shown in Figure 2 is similar to Figures 1 and 3.
Although the amount of main data that can be written is larger than that shown in the figure, since the recording length of the second pilot signal _f2 is different between track A and track B, the recording length of the second pilot signal _f2 is A problem arises in that the time must be switched between track A and track B.

Purpose This invention has been made in view of the above points, and is intended to simplify the configuration of a recording system for a pilot signal for obtaining a tracking signal in a rotating magnetic head type magnetic recording/reproducing device, and to prevent errors in tracking signals. The purpose is to prevent detection from occurring.

Structure Therefore, the tracking signal detecting device in the rotating magnetic head type magnetic recording/reproducing apparatus according to the present invention detects a first pilot signal having a different frequency in a predetermined pilot signal recording area of each track on a magnetic tape.
the pilot signal and the second pilot signal,
a first pilot signal, a second pilot signal,
The first pilot signal is recorded in the order of the first pilot signal, and during playback, the first pilot signal and the second pilot signal are detected from the reproduced signal of each track, and based on the detection result of the first pilot signal of the regular track. generating first and second timing signals for sampling and holding leakage signals of the first pilot signal from both adjacent tracks of the regular track;
The first and second timing signals are enabled and output only when the second pilot signal of the regular track is being detected, and leakage of both adjacent tracks is detected according to the first and second timing signals. The detected values of the first pilot signal are sequentially sampled and held, and the difference between the two held signals is detected and output as a tracking signal indicating the direction and magnitude of tracking deviation.

Embodiments Hereinafter, embodiments of the present invention will be described with reference to FIG. 4 and subsequent figures of the accompanying drawings.

FIG. 4 is a block diagram showing a tracking control system of a DAT, which is a rotating magnetic head type magnetic recording/reproducing apparatus embodying the present invention.

In this magnetic recording/reproducing device, a magnetic tape 1
A magnetic head 6 is provided at a positional relationship of 180 degrees to a rotary head drum 5, which travels with its traveling speed adjusted by a capstan roller 2 and a capstan motor 3, and is rotationally driven by a drum motor 4.
A and 6B scan in helical scan mode.

A disk 7 is connected to the rotating shaft of the drum motor 4 and has magnets 7a and 7b arranged at 180 degrees in correspondence with the magnetic heads 6A and 6B. (hereinafter referred to as "PG head") 8 is arranged.

The timing control circuit 9 controls the switching of each switch and the start and stop of oscillation of the oscillator 11 based on detection signals from the PG head 8 indicating the positions of the magnetic heads 6A and 6B.

The pilot signal generation oscillator (OSC) 11 is
It is controlled by the timing control circuit 9 and outputs a signal f of a predetermined frequency.

Frequency dividers 12 and 13 divide the signal f of a predetermined frequency from the oscillator 11 by a predetermined frequency division ratio, and output a first pilot signal f ₁ and a second pilot signal f ₂ having different frequencies. .

The first pilot signal f ₁ outputted from the frequency divider 12 is a pilot signal that is switched between terminals a and c of a pilot signal changeover switch 14 that is switched and controlled by the timing control circuit 9, and a pilot signal that is switched and controlled by the timing control circuit 9. The signal is input to the recording amplifier 16 via terminals b and c of the /PCM signal changeover switch 15.

Further, the second pilot signal _f2 output from the frequency divider 13 is transferred to the pilot signal changeover switch 1.
4 and between terminals b and c of the pilot signal/PCM signal changeover switch 15.

The recording amplifier 16 receives a pilot signal/
The music signal etc. from the PCM generation circuit 17 is transmitted between terminals a and c of the PCM signal changeover switch 15.
PCM signal is input.

Note that the timing control circuit 9 is connected to the magnetic head 6.
Switch the pilot signal/PCM signal changeover switch 15 to the terminal b side only while A and 6B are located in the predetermined pilot signal recording area (servo area) of each track of the magnetic tape 1, and When the terminal is located at the terminal a, the pilot signal/PCM signal changeover switch 15 is switched to the terminal a side.

These timing control circuits 9, oscillators 11,
The frequency dividers 12 and 13, the pilot signal changeover switch 14, and the pilot signal/PCM signal changeover switch 15 constitute a pilot signal recording means.

The recording amplifier 16 receives the input first pilot signal f ₁ and second pilot signal.
f ₂ , outputs a recording signal V _A obtained by amplifying the PCM signal.

Recording signal output from this recording amplifier 16
V _A is the recording/playback switch 2 that switches to the terminal a side during recording and switches to the terminal b side during playback.
When the head changeover switch 21, which is controlled by the timing control circuit 9, is switched to the terminal a side, the magnetic head 6A is connected between the terminals a and c of the magnetic head 0, and between the terminals c and a, and through the rotary transformer 22A. is supplied, and when the head changeover switch 21 is switched to the terminal b side, the terminal c-
The data is supplied to the magnetic head 6B via the rotary transformer 22B and the rotary transformer 22B, and is recorded on the magnetic tape 1.

Note that the rotary transformers 22A and 22B are built into the drum motor 4.

On the other hand, the pick-up signals from the magnetic heads 6A and 6B which have picked up the recorded signals on the magnetic tape 1 are sent between the rotary transformer 22A and the terminals a and c of the head changeover switch 21, or between the terminals b and b of the rotary transformer 22B and the head changeover switch 21. The signal is output to the reproduction amplifier 24 via the terminals c and b of the recording/reproduction switch 20.

This reproduction amplifier 24 outputs a reproduction signal V _B which is an amplified input pick-up signal, and this reproduction signal V _B is output to a normal reproduction system (not shown) and also to first and second signal detection means. It is also output to the first and second band pass filters 25 and 26.

This first bandpass filter 25 extracts only the first pilot signal f ₁ from the reproduced signal V _B and outputs it as the first reproduced pilot signal f ₁ '.

Further, the second bandpass filter 26 extracts only the second pilot signal f ₂ from the reproduced signal V _B and outputs it as the second reproduced pilot signal f ₂ '.

The pulse generation circuit 27 inputs the second reproduction pilot signal f ₂ ' from the second bandpass filter 26 and generates the input second reproduction pilot signal f 2 '.
By comparing f ₂ ' with a predetermined reference level, the magnetic heads 6A and 6B detect the second track recorded on the track (regular track) on the magnetic tape 1 to be traced.
For example, the detection pulse P _A is outputted at a high level "H" only while the second regenerated pilot signal f ₂ ' obtained by reproducing the pilot signal f ₂ is inputted.

The timing generation circuit 28 includes, for example, a timing signal generation circuit 29 and two AND circuits 30 and 31, as shown in FIG.

The timing signal generation circuit 29 inputs the first reproduction pilot signal f 1 ' from the first bandpass filter 25 and compares this first reproduction pilot signal f _{1 '} with a predetermined reference level. For example, when the first reproduced pilot signal f 1 ' which is reproduced from the first pilot signal f ₁ recorded on the regular track being traced by the magnetic heads 6A and _6B is inputted, a high level "H" is input. A signal (hereinafter referred to as "detection pulse P _B ") is generated.

Using the rising timing of the generated detection pulse P _B as a reference timing _S , first and second timing signals SH ₁ , Output SH ₂ at predetermined time intervals.

On the other hand, the AND circuit 30
The first timing signal _SH1 outputted from the timing signal generation circuit 29 only when the detection pulse P _A from
Output as .

Further, the AND circuit 31 is connected to the pulse generation circuit 27.
The second timing signal _SH2 output from the timing signal generation circuit 29 only when the detection pulse P _A from
Output as .

In other words, the pulse generation circuit 27 and timing generation circuit 28 constitute a sample timing determining means.

On the other hand, the first reproduced pilot signal f ₁ ' outputted from the first bandpass filter 25 is also input to an integrator 34, where it is integrated, and outputted from this integrator 34 as an integrated signal S _A.

The sample and hold circuit 35 samples and holds the integrated signal S _A from the integrator 34 when the first timing signal SH1 from the timing generation circuit 28 is input, and uses this result as a hold signal.
Output as S _B.

The sample and hold circuit 36 samples and holds the integrated signal S _A from the integrator 34 when the second timing signal SH2 from the timing generation circuit 28 is input, and uses this result as a hold signal.
Output as _SC .

The differential amplifier 37 switches the deviation (tracking error) signal S _D corresponding to the difference between the hold signals S _B and S _C from these sample and hold circuits 35 and 36 to the terminal a side during recording, and reproduces it. Terminal b of the recording/playback switch 38 switches to the terminal b side when
-c to the drive circuit 39.

In other words, the differential amplifier 37 constitutes a circuit that detects the difference between the hold signals of the pair of sample and hold circuits 35 and 36 and outputs it as a tracking signal.

A servo signal S _E from a recording servo circuit 40 is also input to the drive circuit 39 via terminals a and c of the recording/reproducing switch 38 .

The drive circuit 39 drives and controls the capstan motor 3 according to the input deviation signal S _D or servo signal S _E.

Next, the operation of this embodiment configured as described above will be explained with reference to FIG. 6 and subsequent figures.

First, during recording, the recording/reproducing switches 20 and 38 are respectively switched to the terminal a side.

Therefore, at this time, the recording servo circuit 40
The servo signal S _E from the
is driven and controlled, and the magnetic tape 1 is running at a constant speed.

On the other hand, the timing control circuit 9 controls the PG head 8.
Based on the detection signal from the magnetic head 6A or 6
When B is located at the starting end of the pilot signal recording area of the track of the magnetic tape 1, the pilot signal/PCM signal changeover switch 15 is switched to the terminal b side, and the pilot signal changeover switch 14 is switched to the terminal a side.

Thereby, the first
The pilot signal _f1 is input to the recording amplifier 16 via switches 14 and 15, and the magnetic head 6A is
or 6B to the first track on the magnetic tape 1.
A pilot signal f ₁ is recorded.

Then, when the magnetic head 6A or 6B has moved relatively by a predetermined amount after being located at the starting end of the pilot signal recording area, the timing control circuit 9 switches the pilot signal changeover switch 14 to the terminal b side.

Thereby, the second
The pilot signal _f2 is input to the recording amplifier 16 via the switches 14 and 15, and the magnetic head 6A or 6B outputs the first pilot signal _f1 to the same track of the magnetic tape 1, followed by the second pilot signal f1. f ₂ is recorded.

Thereafter, when the magnetic head 6A or 6B has further moved relatively by a predetermined amount, the timing control circuit 9 switches the pilot signal changeover switch 14 to the terminal a side.

Thereby, in the same manner as described above, the second pilot signal f ₂ is applied to the same track of the magnetic tape 1.
Subsequently, a first pilot signal _f1 is recorded.

Then, when the magnetic head 6A or 6B has further moved relatively by a predetermined amount, the timing control circuit 9 switches the pilot signal/PCM signal changeover switch 15 to the terminal a side.

As a result, PCM signals such as music signals from the PCM signal generation circuit 17 are subsequently recorded on the same track of the magnetic tape 1.

By performing such an operation for each track of the magnetic tape 1, the first pilot signal f1 and the second pilot signal _f1 are recorded in the pilot signal recording area of each track of the magnetic tape 1, as shown in FIG. Signal f ₂ is recorded next to each other on adjacent tracks in the order f ₁ , f ₂ , f ₁ .

Note that the recording length l _{1 of the first pilot signal f 1 and} the recording length l ₂ of the second pilot signal f ₂ are expressed as l ₁ :l ₂ =
It is recorded so that the relationship is 1:2. Also,
In the figure, P indicates the moving direction of the magnetic heads 6A, 6B.

In this way, the maximum length l of the pilot signal recording area is l=4 when the recording length of the first pilot signal _f1 is set to "1", and in addition, for each track, the maximum length l of the pilot signal recording area is ₄ . The arrangement of the two pilot signals _f2 becomes the same.

Therefore, since the pilot signal recording area is small, the amount of main data that can be recorded increases, and the configuration of the pilot signal recording system is simplified.

Next, during reproduction, the recording/reproduction changeover switches 20 and 38 are switched to the terminal b side.

Therefore, at this time, the deviation signal S _D from the differential amplifier 37 is input to the drive circuit 39 to drive and control the capstan motor 3.

On the other hand, the first pilot signal f ₁ and the second pilot signal f ₂ recorded on each track of the magnetic tape 1 are picked up by the magnetic head 6A or 6B and amplified by the reproduction amplifier 24 to produce the reproduction signal V _B
As the first and second band pass filters 25, 2
6 is input.

Thereby, the first bandpass filter 25
A first reproduced pilot signal f ₁ ' is output from
A second reproduction pilot signal f ₂ ' is output from the second bandpass filter 26.

In this case, the magnetic head 6 with respect to the magnetic tape 1
Since recording by the magnetic heads A and 6B is performed using a tilted azimuth method, a track recorded by the magnetic head 6A (hereinafter referred to as "track A") can obtain a sufficient reproduction level only when traced by the magnetic head 6A; A track recorded with 6B (hereinafter referred to as "track B") can obtain a sufficient reproduction level only when traced with a magnetic head 6B.

However, the first and second pilot signals
Lower the f ₁ and f ₂ frequencies (e.g. 100KHz to several 100K)
Hz), when tracing track A with magnetic head 6A, the pilot signal recorded on track B adjacent to track A is also reproduced, and when tracing track B with magnetic head 6B, the pilot signal recorded on track B is also reproduced. The pilot signal recorded on track A adjacent to track B is also reproduced.

In other words, the reproduced signal V _B includes not only the first and second pilot signals f ₁ and f ₂ recorded on the regular tracks to be traced by the magnetic heads 6A and 6B, but also the regular signals of the magnetic heads 6A and 6B. Also included are first and second pilot signals f ₁ and f ₂ recorded on adjacent tracks depending on the amount of deviation from the track.

For example, as shown in FIG. 7C, the magnetic head 6A
When tracing track A ₂ , the first reproduced pilot signal f ₁ ' traces the first reproduced pilot signal f 1 ' recorded on tracks B ₁ , A ₂ , B ₂ , B ₁ , A ₂ , B ₂ as shown in FIG. 1
This is a sequential reproduction of the pilot signal f ₁ of
The second reproduced pilot signal f ₂ ' is obtained by sequentially reproducing the second pilot signal f ₂ recorded on tracks B ₁ , A ₂ , and B ₂ as shown in FIG.

In this case, the first and second reproduction pilot signals
f ₁ ′ and f ₂ ′ have the highest level when they are the reproductions of the first and second pilot signals f ₁ and f 2 of the regular track A ₂ , and the levels of f 1 ′ and f ₂ ′ are highest when they are the reproductions of the first and second pilot signals f ₁ and f ₂ of the regular track A 2; When the first and second pilot signals f ₁ and f ₂ are reproduced, it is lower than that for track A ₂ ;
Moreover, the larger the amount of deviation of the magnetic head 6A, the higher the level becomes.

Therefore, the timing signal generation circuit 29 of the timing generation circuit 28 first compares the first reproduction pilot signal f ₁ ' with the reference level, thereby
For example, as shown in Fig. 8A, the magnetic head starts at time T1 when it starts tracing the area where the first pilot signal _f1 of the regular track is recorded, and at time _T2 when it finishes tracing the _area . falling,
A detection pulse P _B is generated which rises at time _T5 when tracing of the area where the next first pilot signal _f1 is recorded starts and falls at time _T6 when tracing of that area ends.

Then, at some point while the magnetic head is also tracing the area in which the first pilot signal _f1 of one track adjacent to the regular track is recorded, for example, in the example of FIGS. 6 and 7. Now, in order to sample and hold at the first timing t ₁ which also traces A of track B ₂ , the rising timing of the detection pulse P _B (times T ₁ and T ₅ ) is set as the reference timing S, and from this time For example, at times T ₃ and T ₇ in FIG. 8 after a predetermined period of time has elapsed,
As shown in Figure C, the first timing signal _SH1 is output.

Also, at some point while the magnetic head is also tracing the area in which the first pilot signal _f1 of the other track adjacent to the regular track is recorded, for example, in the example of FIGS. 6 and 7. Now, the second timing t ₂ tracing the lo of track B ₁ .
For example, at time points T ₄ and T ₈ in FIG. 8 after a predetermined time has elapsed from the reference timing S (time points T ₁ and T ₅ ), the second timing is set as shown in FIG. Outputs signal SH ₂ .

On the other hand, the pulse generation circuit 27 compares the second reproduction pilot signal f ₂ ' with the reference level, so that the magnetic head can detect the second pilot signal of the normal track, for example, as shown in FIG. The point at which f ₂ started tracing the area recorded T The point at which it started at ₂ and finished tracing the area
The detection pulse P _A that falls at T ₅ is output to the AND circuits 30 and 31 of the timing generation circuit 28 .

Therefore, the timing generation circuit 28 traces the area where the second pilot signal _f2 of the normal track is recorded while the detection pulse P _A from the pulse generation circuit 27 is rising. In the meantime, only the first and second timing signals SH ₁ and SH ₂ output from the timing signal generation circuit 29 are enabled, and the first and second timing signals SH
1, output as SH2.

That is, as shown in FIG. 8 _E and _F , for example, _{the first} and _second The timing signals SH ₁ and SH ₂ become effective and the first and second
are output as timing signals SH ₁ and SH ₂ .

On the other hand, the first and second timing signals SH ₁ and SH ₂ generated at time points T ₇ and T ₈ when the detection pulse P _A is “L” are invalid and are not output.

Similarly, when the detection pulse P _B rises due to disturbance etc. and the first and second timing signals SH ₁ and SH ₂ are generated, the first and second timing signals SH ₁ and SH ₂ is disabled.

Then, at times T ₃ and T ₄ in FIG. 8 when the first and second timing signals SH1 and SH2 are outputted from this timing generation circuit 28 (the first and second timings t in FIGS. 6 and 7 ₁ and _t2 ), the sample and hold circuits 35 and 36 each sample and hold the integral signal S _A obtained by integrating the first reproduction pilot signal _f1 .

That is, in the example shown in FIG. 7, for example, the level of the leakage signal of the first pilot signal _f1 from track _B2 , that is, the amount of deviation of the magnetic head 6A toward track _B2 , is held in the sample and hold circuit 35. , the sample and hold circuit 36 has a track
The level of the leakage signal of the first pilot signal _f1 from _B1 , that is, the amount of deviation of the magnetic head 6A toward the track _B1 is held.

Therefore, the differential amplifier 37 receives the hold signals S _B ,
Detects the deviation (difference and magnitude of the difference) of S _C , detects the moving direction and amount of movement of the magnetic head, and outputs a deviation (tracking error) signal S _D according to this result to the drive circuit 39. .

Thereby, the rotational speed of the capstan motor 3 is controlled, and the running speed of the magnetic tape 1 is controlled, so that the magnetic heads 6A, 6B accurately trace the regular track.

In this way, in this magnetic recording and reproducing apparatus, the first pilot signal f ₁ and the second pilot signal f ₂ having different frequencies are recorded in the predetermined pilot signal recording area of each track on the magnetic tape.
are recorded in the order of f ₁ , f ₂ , f _{1 ,} and during playback, the first pilot signal f ₁ and the second pilot signal f 2 are detected from the reproduced signal of each track, and the first pilot signal f 1 and the second pilot signal f ₂ are detected. Based on the detection result of _{step 1} , first and second timing signals are generated for sampling and holding leakage signals of the first pilot signal from both adjacent tracks. It is enabled and output only when the pilot signal _f2 of the track is being detected, and the first pilot signal of both adjacent tracks is activated and output using the first and second timing signals.
The detection result of _f1 is sampled and held, and the difference between the hold signals is detected and output as a tracking signal indicating the direction and magnitude of tracking deviation.

As a result, the pilot signal recording area becomes smaller and the amount of information that can be recorded as main data increases, and since the arrangement of the first pilot signal and the second pilot signal is the same for each track, the pilot signal is The configuration of the recording system is simplified.

In addition, by setting the pilot signal recording area, a dedicated track or dedicated head (for example, a track and head for recording CTL signals) for tracking control in conventional VTRs etc. is not required, and other record in area
Since the pilot signal can be recorded with a recording current equivalent to the signal level of the PCM signal, etc., signal detection for tracking control is stabilized.

Furthermore, since the timing signal for sample and hold is valid only when the second pilot signal of the regular track is being detected, even if a timing signal is generated due to disturbance etc., the timing signal will not be invalidated. Therefore, it is possible to prevent erroneous detection of tracking signals due to disturbances, etc.

Although the above embodiment describes an example in which the present invention is implemented in a digital audio tape recorder (DAT), it can also be implemented in other rotating magnetic head type magnetic recording/reproducing devices such as VTRs, data recorders, etc. This can be done regardless of whether it is a device or an analog device.

Effects As explained above, according to the present invention, the first and second pilot signals of different frequencies are recorded in the same order for each track, and the sampling timing of the first pilot signal of the reproduced adjacent track is Since it is enabled only when the second pilot signal of the regular track is being detected, the configuration of the pilot signal recording system for obtaining the tracking signal is simplified, and it is possible to prevent erroneous detection of the tracking signal due to disturbances, etc. It can be prevented.

[Brief explanation of drawings]

FIGS. 1, 2, and 3 are pattern diagrams showing different examples of recording patterns of pilot signals on a magnetic tape, respectively, for explaining a tracking signal detection device in a conventional rotating magnetic head type magnetic recording/reproducing device. FIG. 4 is a block diagram showing an example of a tracking control system in a rotating magnetic head type magnetic recording/reproducing apparatus embodying the present invention, and FIG.
Similarly, FIG. 4 is a block diagram showing an example of the timing generation circuit, FIG. 6 is a pattern diagram showing the recording pattern of the pilot signal on the magnetic tape, which is used to explain the operation of FIG. 4, and FIG. 1. An explanatory diagram showing an example of the relationship between the level of the second reproduced pilot signal and the recording pattern of the pilot signal. FIG. 8 is a timing chart diagram showing the timing of the output signals from the timing generation circuit and the pulse generation circuit as well. It is. 1... Magnetic tape, 3... Capstan motor, 6A, 6B... Magnetic head, 9... Timing control circuit, 11... Oscillator, 12, 13... Frequency divider, 14... Pilot signal changeover switch ,
15... Pilot signal/PCM signal switching switch, 20, 38... Recording/playback switching switch, 25... First band pass filter (first signal detection means), 26... Second band pass filter ( second signal detection means), 27... pulse generation circuit, 28... timing generation circuit, 35, 3
6...Sample hold circuit, 37...Differential amplifier.

Claims (1)

[Claims] 1. In a rotating magnetic head type magnetic recording/reproducing device, a first pilot signal and a second pilot signal having different frequencies are recorded in a predetermined pilot signal recording area of each track on a magnetic tape. a pilot signal recording means for recording the second pilot signal and the first pilot signal in this order; and a first signal detecting means for detecting the first pilot signal from the reproduction signal of each track on the magnetic tape during reproduction. and a second signal detection means for detecting the second pilot signal, and for sampling and holding leakage signals of the first pilot signal from both adjacent tracks based on the detection results of the first signal detection means. A sample in which first and second timing signals are generated, and the first and second timing signals are enabled and output only when the second signal detection means detects the second pilot signal. a timing determining means; a pair of sample and hold circuits that sample and hold a detection result of the first signal detection means in accordance with first and second timing signals from the sample timing determination means; and this pair of sample and hold circuits. 1. A tracking signal detection device, comprising: a circuit for detecting a difference between signals held at the same time and outputting the detected difference as a tracking signal.