JPS6022761A - Recording and reproducing method of digital signal - Google Patents

Abstract

PURPOSE:To improve the accuracy of tracking control in a reproduction time and to attain the interchangeability among devices by performing the tracking control of a rotary head in a normal reproduction time or a variable speed reproduction time including a double speed, triple speed, etc. CONSTITUTION:In a normal reproduction time the signals extracted out of a tape 2 by rotary heads 1A and 1B are supplied to a switch circuit 19 and then switched alternately between a half revolving period tA including the tape contact period of the head 1A and a half revolving period tB including the tape contact period of the head B like a recording time by the switch signal given from a timing signal generating circuit 10. Thus an intermittent PCM signal SR is obtained for each segment. This signal SR is supplied to a reproduction processor and demodulated to the original PCM signal to be supplied to a decoder. Then the data is detected for each block by the block synchronizing signal, and at the same time the error correction, the deinterleave, etc. are carried out to reset the PCM signal to an analog audio signal by a D/A converter. This audio signal is sent to the output side.

Description

[Detailed Description of the Invention] Industrial Application Field This invention converts, for example, a video signal or an audio signal into a PCM signal, and converts it into a PCM signal by rotating it in units of time. The present invention relates to a method for recording and reproducing digital signals suitable for recording and reproducing the same.

BACKGROUND TECHNOLOGY AND PROBLEMS A helical scan type rotary head device records video and audio signals on a magnetic tape once per unit time.
When recording by forming diagonal tracks one by one and reproducing them, it has been considered to record and reproduce video signals and audio signals by converting them into PCM. This is because PCM allows high-quality recording and reproduction.

In this case, the tracking control to ensure that the rotary head correctly scans the recording track during playback is as follows:
Conventionally, a control signal recorded on one end of the tape in the width direction by a fixed magnetic head is reproduced by the fixed head, and the reproduction control signal and the rotational phase of the rotary head have a constant phase relationship. This is usually done by

However, in this method, a fixed magnetic head must be specifically provided for tracking control.

Providing such a fixed magnetic head is inconvenient when it is desired to downsize the recording/reproducing apparatus due to the mounting location and the like.

Therefore, the present applicant previously proposed a method of controlling the tracking of a rotary head for reproduction by using only the reproduction output of the rotary head for reproduction without using this fixed head.

In this method, PCM signals can easily be compressed and expanded on the time axis, so unlike analog signals, it is not necessary to record and reproduce the signals continuously in time.
This method was developed based on the fact that it is easy to record this PCM signal and a separate signal by dividing the area into the tracks of a book.

In other words, when compressing the time axis of a PCM signal and recording diagonal tracks using a plurality of rotating heads on a recording medium without forming a guard band, the PCM signal is recorded in the longitudinal direction of each trunk. Multiple tracking pilot signals are recorded independently as areas, and during playback,
A recording track is scanned by a rotary head whose scanning width is wider than the width of the trunk, and the tracking of the rotary head is controlled by the reproduction output of pilot signals from tracks on both sides of the track being scanned.

The reference signal for recording and reproducing this tracking pilot signal is a 30Hz pulse signal (P C) is used.

However, even during playback, if the PG multiplied signal is used as a detection position reference when reproducing the tracking pilot position, the PG multiplied signal reference position may shift due to mechanical changes in the equipment over time, temperature changes, etc. , which appears as a kind of steady amount of tracking error (offcent) during playback.

For this reason, it becomes difficult to reproduce the tracking pilot signal at the same timing as during reproduction and recording, and to control the rotary head, and there is a problem in particular that compatibility between devices becomes incompatible.

Since the sampling pulse that obtains the reproduced output of the tracking pilot signal is formed over a period of time, the error increases in the form of an integrated signal and is affected by so-called jitter, causing the position of the sampling pulse to shift. There is.

Furthermore, when considering tracking control in a rotary head type recording/reproducing apparatus, it is necessary to consider not only normal reproduction but also variable speed reproduction in which the tape speed is different from that during recording.

Purpose of the Invention In view of the above, the present invention provides a method for reliably reproducing a tracking pilot signal without being affected by mechanical aging, temperature changes, or jitter of the device, not only during normal reproduction but also during variable speed reproduction. To provide a digital signal recording and reproducing method that can correctly control a rotating head, ensure compatibility between devices, and simplify the circuit configuration when performing reproduction by switching between multiple reproduction speeds. be.

Summary of the Invention The present invention provides a method for compressing the time axis of a digital signal, forming and recording diagonal tracks on a recording medium using a plurality of rotary heads without forming a guard band, and reproducing the same. A plurality of tracking pilot signals are recorded in the longitudinal direction of each track as a recording area independently from the digital signal, and when the recording track is scanned by a rotary head whose scanning width is wider than the width of the track at the time of 4th generation. , during the first scanning period, a pulse signal is formed υ based on the own reproduction output of the pilot signal recorded on the track currently being scanned, and during the second scanning period, a pulse signal is formed on the track currently being scanned. A pulse signal is formed based on the reproduced output of the pilot signal recorded in ζ, and during the period of each of these pulse signals, the pilot signal is detected from the adjacent track being scanned by the rotary head. It is configured to perform tracking control of the above-mentioned rotating head based on the output.
This makes it possible to reliably reproduce the tracking pilot signal and control the tracking of the rotating head without being affected by mechanical changes over time, temperature changes, or thin tubes of the device, thereby ensuring compatibility between devices. can be achieved. Further, the circuit configuration when performing reproduction by switching between a plurality of reproduction speeds can be simplified.

EXAMPLE Hereinafter, an example of the present invention will be described in detail based on FIGS. 1 to 11.

Figure 1 shows the circuit configuration of this embodiment.
Only the circuit configuration for recording a tracking pilot signal, which is directly related to this invention, and reproducing it by switching between normal playback and variable speed playback, for example, double speed and triple speed, is shown. The reproduction circuit configuration is omitted.

In the figure, (IA) and (IB) are rotating heads, (
2) is a magnetic tape as a recording medium. The rotating heads (IA) and (IB) are arranged around the periphery of the drum (3) at equal angular intervals, i.e. 180 degrees apart, as shown in FIG. On the other hand, the magnetic tape (2) is wound around the circumferential surface of the tape guide drum (3) over an angular range of, for example, 90 degrees, which is narrower than each range of 180 degrees. Then, the rotating heads (18) and (IB) are rotated at a rate of 30 revolutions per second in the direction of arrow (411), and the tape (2) is run at a predetermined speed in the direction shown by arrow (4T). Then, the rotary head (l^) and (IB) make a diagonal one on the magnetic tape (2) as shown in Fig. 3.
Each magnetic track (5Δ) (5B) is formed, for example, in a so-called overwritten state. That is, the width (scanning width) W of the headgear knob is made larger than the track width. In this case, head (1^) and (
The width directions of the gaps IB) are set in different directions with respect to the direction orthogonal to the scanning direction. In other words, the so-called azimuth angles are made different.

Then, a period (in this example, a period corresponding to an angular range of 90 degrees) occurs during which the two rotating heads (IA) and (IB) do not come into contact with the tape (2), and this period is utilized. The apparatus can be simplified by adding redundant data during recording and performing correction processing during reproduction.

(6) is an oscillator that generates a tracking pilot signal P, and the pilot signal P has a frequency r1 with a relatively small value of azimuth loss, for example, about several hundred kllz, and is recorded at a relatively high level. Ru. (7)
is a recording waveform generation circuit, which includes an edge detection circuit (
8), and based on the pilot signal from the oscillator (6), a predetermined time tp (tp is each pilot signal (9) A pilot signal having a recording time of
is a switch circuit for switching the rotary heads (IA) and (IB), and is switched by a switching signal 31 (FIG. 4A) from a timing signal generating circuit αΦ.

This timing signal generation circuit (II) includes a rotary head (1Δ) (IB) obtained in synchronization with the rotation of a rotary drive motor (12) for a rotary head (IA) (IB) from a pulse generator (11). A pulse PG of 30 tlz indicating the rotational phase of The rotation phase of is controlled.

The pilot signal from the switch circuit (9) switched by the switch signal S1 from the timing signal generation circuit Ql is amplified by the amplifier (14A) or (14B) and then sent to the contact point of the switch circuit (15A) or (15B), respectively. It is supplied to the rotary head (IA) or (IB) via the R side and recorded on the magnetic tape (2). Switch circuit (15A
) and (15B) are connected to the R side during recording, and are switched to the P side during playback.

Also, the output signal S from the timing signal generation circuit eraω
2 (Fig. 4C) is supplied to the delay circuit (16), and this
Rotating head <IA) (1B) and pulse generator (11
) is applied to one input side of the edge detection circuit (8), and edge detection is performed as a recording reference for the pilot signal. The fall of the signal 83 (FIG. 4D) delayed by the delay circuit (16) is made to coincide with the time when the first hand contacts the tape during one rotation period.

Further, the signal from the delay circuit (16) has a delay time T corresponding to a half rotation period of the head, and a pilot signal from the end of the track (the rear trunk of the two tracks formed during one rotation period). It is supplied to a delay circuit (17) having a delay time +-tp corresponding to the distance to which the edge was first recorded, and is then delayed by a time T+-tP to the other input of the edge detection circuit (8). Edge detection is performed to determine the basis for the start of recording of a pilot signal by the head (l^) relative to one rotating head, that is, in this case head (IB) relative to the other head.

(18A) (18B) is the switch circuit (
158) An amplifier to which the playback output from the corresponding rotary head CIA) (IB) is supplied when (15B) is switched to the contact P side, and these amplifiers (18A
) (18B) are supplied to a switch circuit (19). The switch circuit (19) uses a 30Hz switching signal 81' (FIG. 5A, FIG. 9A, and FIG. 11A) from the timing signal generation circuit aΦ to switch the head (
During the half-rotation period including the tape contact period of 1^) and the head (
IB) is alternately switched with a half-rotation period including the tape contact period.

(20) is the passing center frequency f for extracting only the pilot signal P from the reproduction output from the switch circuit (19).
(21) is a peak hold circuit for holding the peak value of the output of the filter (20) in order to improve response characteristics; (22) is a peak hold circuit for sampling the held peak value. (23) is a comparison circuit for comparing each output of the peak hold circuit (21) and the sampling hold circuit (22), for example, a differential amplifier; (24) is a differential amplifier (23) This is a sampling and holding circuit for sampling and holding a comparison error signal from
2) As will be described later, (24) essentially applies to both ends of the tracks on both sides adjacent to the track currently being scanned during normal playback, and to the central part of the track currently being scanned during double-speed playback. During triple-speed playback in the center section, the crosstalk of each biloft signal recorded in the center portions of the tracks on both sides adjacent to the trunk being scanned is sampled and bolded.

The output of the sampling hold circuit (24) is taken out as a tracking control signal to an output terminal (25).

Further, in order to form sampling pulses etc. for the sampling and hold circuits (22) and (24), a waveform shaping circuit (26) is provided on the output side of the bandpass filter (20) to substantially detect the edges of the pilot signal. is provided, and its output signal is supplied to the delay circuit (27).
The signal Sv delayed by a predetermined time tm (Fig. 5 J,
Figures 9F and 11E) are obtained. This delay circuit (
27) Delay time in 1. is provided as a countermeasure against dropout of the pilot signal, and it is sufficient that the recording time of the pilot signal is longer than tp, and preferably Lm=
It is tp.

(28) and (29) are the signals S from the delay circuit (27)
These are a rising detection circuit and a falling detection circuit for detecting the rising edge and falling edge of signal S7, respectively, and as will be described later, during normal playback and triple speed playback, the rising edge and falling edge of signal S7 are detected every half rotation period of the head. The falling edge of the signal S7 is detected, and only the rising edge of the signal S7 is detected in any period during double speed playback. A switch circuit (30) is provided on the output side of the detection circuits (28) and (29), and is switched by a switching signal Ss' from the timing signal generating circuit +II. When the signal St' is high level (period 8), it is connected to the contact a side to take out the output of the rising edge detection circuit (28), and when the signal St' is high level (period 8), it is connected to the contact a side and takes out the output of the falling detection circuit (29). ).

Furthermore, the rise detection circuit (2 days) and switch circuit (3 days)
A switch circuit (31) is provided on the output side of the mode setting circuit (32), and this switch circuit (31) is a contact when a command signal for setting the double speed playback mode is generated from the output terminal X2 of the mode setting circuit (32). It is connected to side A to take out the output of the rise detection circuit (28), and on the other hand, it contacts when the command signal for setting the double speed playback mode is not generated, that is, during normal playback or triple speed playback other than double speed playback. is connected to take out the output of the switch circuit (30).

Therefore, during double-speed playback, the head has a half-rotation period tB.

Regardless of tA, only the rising edge of the output S7 is detected and output; on the other hand, during normal playback and triple speed playback, the rising edge of the signal S7 is detected in the period tB, and the rising edge of the signal S7 is detected in the period tA. It will be output.

The output of the switch circuit (31) is connected to a plurality of gate circuits (3
31), (332), (333), (334) and (33s), and their gate signals include, for example, the wind signals S1 to S5W5 (No. 5C-G) are used. The window signal generation circuit (34) counts the clocks from the clock terminal (42) in response to the output signal S2 from the timing signal generation circuit aΦ, and counts the clocks from the clock terminal (42) with a predetermined width that can cover at least both ends of the above-mentioned signal S7. A plurality of wind signals are generated depending on the playback mode. That is, when the window signal generation circuit (34) receives a command signal for setting the normal playback mode from the output terminal When receiving the command signal to set the double speed playback mode, the window signals SW2 and SW6 are
When it receives a command signal to set the triple speed playback mode from the output terminal X3, it generates the window signals Sw2 and Sw+.

Therefore, on each output side of the gate circuits (331) to (336), only the 8 signals entered within the period of these wind signals SWi to Sw5 are output signals S@ (Fig. 5K , FIG. 9G and FIG. 11F), passes through an OR circuit (35), and is supplied essentially as a start pulse to one input side of a delay circuit (36) using a counter, for example.

Also, multiple delay time setting circuits (3B), (39)
.

(40) and (41) are provided, and the setting circuit (38) substantially controls the pilot signal from the time of generation of the signal S8 during the first half-rotation period of the head during normal playback or triple speed playback, for example, within the period tB. The setting circuit (39) sets a delay time t8 until the start of sampling, and during normal playback, the setting circuit (39) determines whether the signal S8 is generated last during the first half-rotation period t13 during the next half-rotation period of the head, for example. The setting circuit (40) sets the delay time tb up to the actual sampling point of the first pilot signal performed within the period tA, and sets the delay time tb of the signal S8 within the period t'A during normal playback or triple speed playback. The setting circuit (41) sets a delay time tc from the time of occurrence to when the pilot signal is substantially started to be sampled, and the setting circuit (41) substantially samples the pilot signal from the time of occurrence of the signal S8 in the period LB+tA during double speed playback. Set the delay time td until the start.

Each delay time set in the setting circuits (38) to (41) in this way is determined by the window signal S from the window signal generation circuit (34) in the delay time setting selector (37).
Wt~SWS is selected and supplied to the other input side of the delay circuit (36). Therefore, the delay circuit (36), which is a counter, counts the clock from the clock terminal (42) for a set time using the signal S6 as a start pulse, and at the end of counting, a narrow signal S is sent to the output side of the delay circuit (36).
s (FIG. 5 L5, FIG. 9 H, and FIG. 11 G).

(43) is a pulse generation circuit using a counter, for example, which counts the clock from the clock terminal (42) using the signal S9 from the delay circuit (36) as a trigger pulse, and generates a pulse for a predetermined duration ti at a predetermined interval to. A pair of pulses PI (FIG. 5M1, FIG. 9I and FIG. 11H) having a pulse width (see FIGS. 6-8) is generated corresponding to each pilot signal to be detected. This pulse Pi is supplied to a peak hold circuit (21) and also to a sampling pulse generation circuit (44) using, for example, a D-type flip-flop circuit.

The sampling pulse generation circuit (44) generates a pair of pulses P
i, a pair of sampling pulses SP1 . SP2 is generated for the sampling hold circuits (22) and (24).

Next, the operation of the circuit shown in FIG. 1 will be explained with reference to the signal waveforms shown in FIGS. 4 to 11.

First, during recording, in response to the pulse PC from the pulse generator (11) indicating the rotational phase of the rotary heads (IA) (IB), the timing signal generating circuit α0) outputs the pulse signal shown in FIG.
A signal S2 as shown in FIG. 4 is generated, and this signal S2 is delayed by a predetermined time TR in a delay circuit (16), so that a signal S3 as shown in FIG. 4 is outputted to its output side. This signal S3 is supplied to an edge detection circuit (8), where its edge (falling edge) is detected, and in synchronization with this edge, a narrow-width signal as shown in FIG. 4E is sent to its output side. S4 is generated and supplied to the recording waveform generation circuit (7).

The detection time of the signal S4 at this time is made to approximately coincide with the time when the head (IB) actually contacts the tape (2) for the first time, and this sets the standard for starting recording of the pilot signal by the head (IB). can be determined.

The recording waveform generating circuit (7) generates the biloft signal P from the oscillator (6) at a predetermined interval T in synchronization with the supplied signal S4.
The signal Se, which is an intermittent pilot signal as shown in FIG. 4G, is taken out on the output side.

Further, the signal S3 from the delay circuit (16) is transmitted to the delay circuit (16).
7). This delay circuit (17) synchronizes with the falling edge of the signal S3 and a fourth delay circuit (17) having a duration T-2tP.
A signal S5 as shown in FIG. F is generated. This signal S6 is supplied to the edge detection circuit 8), where its edge (falling edge) is detected as described above, and in synchronization with this edge, the output side is outputted as shown in the right part of FIG. 4E. A narrow signal S4 is generated and supplied to the recording waveform generation circuit (7).

The signal S4 at this time determines the reference for starting recording of the pilot signal by the head (IA).

In this case as well, the recording waveform generation circuit (7) sends the biloft signal P from the oscillator (6) at predetermined intervals To for a predetermined time tp in synchronization with the supplied signal S4, while the recording waveform generation circuit In response to the pulse PC from the pulse generator (11), a switching signal S1 as shown in the fourth prisoner is generated, and this signal S1 is transmitted to the rotating head C.
The head (18) is synchronized with the rotation of the tape (IB), and as shown in FIGS.
) and the signal S1 is at a low level during the half-rotation period t.
In B, the head (IB) is in contact with the tape (2). Then, the switch circuit (9) is in the state shown in the figure during the period tA and in the state shown in the figure during the period tB by the switching signal S1.
Then, the state is changed to the state opposite to that shown in the figure, and head switching is performed.

Therefore, the pilot signal S6 at the predetermined interval To obtained on the output side of the recording waveform generation circuit (7) is transmitted to the switch circuit (9).
) is in a state opposite to that shown in the diagram, the amplifier (14
B) and the R side of the switch circuit (15B) to the head (IB), and the third
As shown in the figure, the geometric ratio 111β (T) from the longitudinal center position of the track (5B).

Tracking signal recording area ATL provided at both ends of the track (5B) in the longitudinal direction, separated by
and AT2, and a similar recording area AT3 provided in the center of the track (5B), respectively, for a time tp. - On the other hand, when the switch circuit (9) is in the state shown in the figure, the pilot signal S6 is transmitted to the amplifier (]4Δ) and the switch circuit I
It is supplied to the head (1Δ) through the R side of I (158), and at the beginning, middle and end of the contact period of the head (18) to the tape (2) within the period tA, as shown in the same figure. As shown, ffCT is equidistant from the longitudinal center position of the track (5A).
recording areas AT1 and AT2 similar to the above provided at both ends of the track (5A) in the longitudinal direction separated by
and further recorded for a time tp in a similar recording area AT8 provided at the center of the track (5Δ).

In addition, at times other than the time when these pilot signals S6 are recorded, one track (not shown) is recorded as one track.
The audio PCM signal of the segment part is supplied to the head (1Δ) through the amplifier (14^) during period tA, and is supplied to the head (IB) through the amplifier (14B) during period tB.
are supplied to each track (5^) (5B) in a recording area APL+ other than the above-mentioned pilot signal recording area.
Recorded in AP2 and AP8.

Next, reproduction of the signal recorded as described above will be explained.

Also during this reproduction, drum phase servo is applied to the motor (12) by the phase servo circuit (13) in the same manner as during recording.

First, during normal playback, the rotating head (IA)
The signals extracted from the tape (2) by (IB) are transmitted through the contact P side of the switch circuit (15A) and the amplifier (18^), and the contact P side of the switch circuit (15B) and the amplifier (18B). It is supplied to the switch circuit (19). This switch circuit (19) uses a switching signal s11 of 3011z as shown in FIG.
The head (I
It is alternately switched with a half-rotation period tB including the tape contact period of B). Therefore, this switch circuit (19
), an intermittent PCM signal sR of one segment as shown in FIG. Data for each block is detected by the °ζ block synchronization signal, and is subjected to processing such as error correction and de-interleaving, and is returned to an analog audio signal by a D/A converter and output to the output side.

Tracking control is performed as follows.

Now, for example, the scanning width W where the head (IB) includes the trunk (5B2) as shown by the dashed line in FIG.
, the head (IB) scans the tracks (582) (57) on both sides of this trunk (5B2).
h) and scan across the area AT as shown in FIG.
1 smell ′ζ is the pilot signal P of the trunk (582)
A2, the pilot signal PI]2 of the track (5A2) on both sides and the pilot signal pe1 of the track (5A1) are reproduced, and in the area ATa, the track (
The pilot signal PA4 of the trunk (5B2) and the pilot signal PB4 of the trunk (5A2) on both sides and the pilot signal PA4 of the truck (5B2)
A1) and the pilot signal PB9 of area A are regenerated.
At T2, the pilot signal P of the truck (5B2)
^6, the pilot signal P Bla of the trunk (5A2) on both sides, and the pilot signal pBs of the trunk (581) are reproduced. At this time, the reproduction output of the head (IB) from the switch circuit (19) is supplied to a narrow band band pass filter (20) with a passing center frequency f1, and as shown in FIG. Only the signal is taken out and this is passed through the peak hold circuit (21
).

In addition, the output SF of the band pass filter (20) is waveform-shaped into a rectangular wave by the waveform shaping circuit (26) and then supplied to the delay circuit (27), so that its rear part is substantially delayed by a predetermined time tm. A signal S7 as shown in FIG. 5J is obtained. This signal S7 is transmitted to the detection circuits (28) and (29).
), whose rising and falling edges are detected respectively, and during the period tB during scanning by the head (IB), the rising edge of the signal S7 detected by the detection circuit (28) is detected by the switch circuit (30). Contact a side and switch circuit (31)
Gate circuit (331) to (33s) through the contact side of
while the period tA during scanning at lid (l^)
Then, the falling edge of the signal S7 detected by the detection circuit (29) passes through the contact side of the switch circuit (30) and the contact side of the switch circuit (31) to the gate circuits (331) to (
33s).

Further, during normal playback, a setting instruction signal from the output terminal X1 of the mode setting circuit (32) causes the window signal generation circuit (34) to generate a signal as shown in FIG. ) In response to S2,
Wind signals SW1 to SWS as shown in FIG. 5 C-G
are generated sequentially and the gate circuits (331) to (33s)
Therefore, only the rising or falling edge of the signal S7 that entered during each period of the window signals SW1 to SW5 is substantially taken out to the output side of these gate circuits, and as a result, Gate circuit <331
) to (33s), as shown in FIG. A narrow signal S8 corresponding to the falling edge of is obtained.

This signal S8 is supplied to a delay circuit (36).

At this time, the selector (37) selects the delay time setting circuits (38) to (40) to set each delay time ta.

tb and tc are set for the delay circuit (36).

During the period tB, the delay circuit (36) sequentially generates the signal S9 delayed by the time ta from the signal S8, as shown in the left part of the fifth diagram, and during the period tB, as shown in the center part of the fifth diagram. In the step of changing the period from tB to 8, the first signal S9 during the period tA is generated with a delay of the period tB from the time when the last one of the signals S8 generated during the period tB is generated; During a period tA after the first signal Ss is generated, a signal S9 delayed by a time tc from the signal S11 is generated, as shown on the right side of the fifth diagram.

This signal S11 is supplied to the pulse generation circuit (43),
Based on the signal Ss, a pair of pulses Pi corresponding to each pilot signal to be detected is formed as shown in FIG. 5M, and the sampling pulse generation circuit (44)
and supplied to the peak hold circuit (21)! It will be done. Then, the sampling pulse generation circuit (44) generates sampling pulses SP and SF3 as shown in FIG. 5 N and O based on the pair of pulses Pi.
The signals are supplied to sampling and hold circuits (22) and (24), respectively.

Here, the relationship between the above-mentioned delay times ta, tb, and tc and the formation of the sampling pulses SPz and SF3 will be further explained in detail with reference to FIGS. 6 to 8.

First, during the period tB, as shown in FIG. 6, the starting point of the filter output SF (FIG. 6A) (PA21
A4. After a delay time La elapses from the signal Ss (FIG. 6B), which is formed so as to coincide with the starting edge of PA@ (corresponding to the starting edge of
pulse ptt lasts for time 11, from which time t
After o a second pulse PI2 occurs which likewise lasts for the time t1. Templing pulse 5P1 (Fig. 6D) is generated at the falling edge of the first two pulses, and sampling SP2 (Fig. 6D) is generated at the falling edge of the second pulse PL2.
FIG. 6E) is generated. Note that the relationship between each delay time at this time is t a = -t p.

In addition, in the transition period from period tB to 18, as shown in FIG. The first two pulses of Pi rise and last for a time ti, and so on.
A second pulse PL2 is generated at an interval of time to,
Although not shown, these are the first and second pulses P and PI3.
At the falling edge of the sampling pulses SPi and SF3, respectively
is generated. Note that the time tb is, for example, t
b -T-2To --t i.

Furthermore, in the period t^, as shown in FIG. 8, the final pilot signal PB2 or PH of the first region in the period tA is
1, the first pulse Pit of the pair of pulses Pi rises after a delay time tc of the fall of the signal S7, which is delayed by a time tI11 from the part corresponding to the end of the signal S7, and reaches a time ti.
Similarly, second pulses P12 are generated at intervals of time to, and sampling pulses SP1 and SP12 are generated at the falling edges of the first and second pulses P11 and P12, respectively (not shown). SF3 is generated. Incidentally, the time tc is defined as (tc = To 3 tp
-tm +-tpThe pulse Pi thus obtained is supplied to the peak hold circuit (21), and the sampling pulse SP is formed based on this pulse P+.
1 and SF3 are each sampling hole once II (22
) and (24).

Therefore, while the head (IB) is scanning the trunk (582), as is clear from FIGS. 5 and 6, the first pulse ptt of the pulse Pi is at the arrow (4T) (FIG. 3) The pilot signal PB2. of the adjacent truck (5A2) on the opposite side to the transport direction shown. The crosstalk of PB4 and pee is held at its peak in the peak hold circuit (21), and at this time the peak hold circuit (21)
The output of 9 is supplied to the sampling hold circuit (22), where it is sampled by the sampling pulse SPi generated at the falling edge of the first two pulses, and is sent to the differential amplifier (23) as a leading phase tracking signal. Supplied to one input end.

Further, the second pulse P12 of the pulse Pi is the biloft signal P B of the adjacent track (5^1) on the tape transport direction side.
The crosstalk of i+ P ea and pBs is held at its peak in the peak hold circuit (21), and the output of the peak hold circuit (21) at this time is sent to the other input terminal of the differential amplifier (23) for tracking of the delayed phase. Supplied as a signal. Therefore, the differential amplifier (
23) are pilot signals PB2 and PBl, Pe4 and Pe
The tracking signals corresponding to the crosstalk of 1t, PBII, and pes are sequentially compared.

The comparison error signal from the differential amplifier (23) is then supplied to the sampling hold circuit (24), where it is sampled by the sampling pulse SP2 generated at the falling edge of the second pulse PL2.

Therefore, from this sampling and hold circuit (24), the difference in power between the two persons to the differential amplifier (23) is obtained as a tracking control signal, and this is supplied from the output terminal (25) to the capstan motor (not shown) to record the tape. The amount of transfer is controlled, the level difference between the two people's power to the differential amplifier (23) is zero, the head (IB) is on the track (5
When scanning B2), the two tracks on both sides (5
^2) and (5A1) by the same amount. That is, the head (IB) is controlled to scan so that the center position of the gap in the width direction coincides with the center position of the track (582).

The same process is performed for other tracks. For example, when the head (1^) scans the track (5A2), as shown on the right side of FIG. and (5B2) biloft signal PA
?・PAR・PAI and PA2・PA4・PA
Since the crosstalk of lI is obtained, the peak hold circuit (21) sequentially holds the peaks of these as described above, and the sampling pulse S is supplied from the sampling pulse generation circuit (44) to the sampling hold circuit (22).
Pilot signal PAt+PA*+PA by P1
11 crosstalk is sampled to obtain a tracking signal, which is supplied to the next stage differential amplifier (23) and a pilot signal P A2 r P A4 +PA8
Peak hold circuit (21) corresponding to crosstalk
Here, the tracking signals corresponding to the crosstalk of the pilot signals P^7 and PA2, P^8 and PA4, and PAst and P8 are compared, and the comparison error signal is sampled and held. By sampling with the sampling pulse SP2 supplied to the circuit (24), a tracking control signal for the head (l^) can be obtained.

Also, in the same way, move the track (58g) to the head (IB).
When scanning, as shown in FIG.
Since the crosstalk of +PB8 is obtained, the crosstalk of the pilot signal Pet+Pes+PBll is sampled with the sampling pulse SP1, and the differential amplifier (
23), the pilot signal PRY and PH1 and 2 days. and P
A trunking control signal for the head (IB) can be obtained by comparing the tracking signals corresponding to the crosstalk of H4, Ptn1 and pee, and finally sampling the comparison difference signal with the sampling pulse SP2. .

Next, when going back at double speed, the 3rd v! J with broken line TD
Scan so that the center of the gap width of the rotary head passes through the position shown in . In other words, one of two adjacent recording tracks (5A) (5B) formed by two rotary heads with different azimuth angles during recording, for example, track (5B).
is scanned in the first half of the tape contact period of each rotary head (111) (IB), while the track (58), for example, is scanned in the second half.

With this scanning method, the rotary head (IA) and the
The signals extracted from the tape (2) by B) are sent to the contact P side of the switch F-1i 21 path (15A) and the contact P side of the amplifier (18A) and switch circuit (15B).
It is supplied to the switch circuit (19) via the side and amplifier (18B). This switch circuit (19) is a timing signal generating circuit (3011 from Im as shown in FIG. 5A).
z switching signal St' causes the head (17
The half-rotation period tA including the tape contact period of 1) and the half-rotation period ts including the tape contact period of the head (IB) are alternately switched. Therefore, this switch circuit (
19), an intermittent PCM signal sR of one segment as shown in the fifth diagram is obtained, which is supplied to a reproduction processor (not shown), demodulated to the original PCM signal, and further supplied to a decoder. Data for each block is detected by the block synchronization signal, and is subjected to processing such as error correction and de-interleaving, and is converted back to an analog audio signal by a D/A converter and outputted to the output side.

Trunking control is performed as follows.

Now, for example, the head (IB) straddles two tracks (5B2) (5A2) in FIG. 3 as shown by the broken line 'r.

If you scan in the direction shown, the head (1B)
As shown in FIG.
1h) and regenerates the pilot signal PB1 in the area A T
9, the pilot signal P of the truck (5B2)
^→ and the pilot signal P of the adjacent truck (5A2)
B4, and in area AT2, track (5^
Pilot signal P of trunks (583) on both sides of 2)
Pilot signal of Ai□ and truck (5B2)
P Ae and the pilot signal P of the truck (5A2)
Play Be. At this time, the reproduced output of the head (IB) from the switch circuit (19) is supplied to the narrow band band pass filter (20) with a passing center frequency f1.
As shown in Figure E, only the pilot signal is extracted as the output SF, and this is sent to the peak hold circuit (21).
supplied to

Further, the output SF of the band pass filter (20) is shaped into a rectangular wave by the waveform shaping circuit (26) as described above, and then supplied to the delay circuit (27), so that the rear part thereof is substantially fixed for a predetermined time tI11. A signal S7 as shown in FIG. 9F is obtained, which is delayed by . This signal S7 is transmitted to the detection circuit (28
) and (29), and their rise and fall are detected respectively, but in this case, the head (I
In both the scanning period ta in B) and the scanning period tA in the head (1^), only the rising edge of the signal S7 detected by the detection circuit (28) is connected to contact a during double-speed playback.
It is supplied to gate circuits (33z) to (33s) via a switch circuit (11) that is switched to the side.

In addition, during double speed playback, the window signal generation circuit (34) generates wind signals SW2 and Sws as shown in FIG. 9B and C in response to a setting instruction signal from the output terminal X2 of the mode setting circuit (32). The gate circuit (33
2) and (33s) as a gate signal, and therefore, only the rising edge of the signal S7 that entered during each period of the window signals SW2 and SW6 is substantially taken out to the output side of these gate circuits. , As a result, the OR circuit 1 on the output side of the gate, circuits (332) to (33G)
On the output side of 21% (35), as shown in Figure 9G,
In both periods tB and tA, a narrow signal S8 matching the rising edge of the signal S7 is obtained.

This message JP) S e is a delayed time! 1P1 (36).

Also, at this time, the selector (37) selects the "ζ delay time setting circuit (41), and the delay time td is set by the delay circuit (36).
) is set to 6. The delay circuit (36)
In B, as shown in the left part of FIG. 9, the signal S
8, a signal S9 delayed by a time td is generated, and the signal S9 is delayed by a period td.
Similarly, at A, as shown in the right part of FIG. 9H, the signal S
9, a signal S8 delayed by a time td is generated.

This signal S9 is supplied to a pulse generation circuit (43), where, based on the signal S9, a pair of pulses P corresponding to each pilot signal to be detected is generated as shown in FIG.
i is formed and supplied to the sampling pulse generation circuit (44) and the peak hold circuit (2L). and,
The sampling pulse generation circuit (44) generates sampling pulses SPt and SF3 as shown in FIG. 9 J and K based on the pair of pulses Pi, and the sampling pulses SPt and SF3 as shown in FIG. supplied to

Here, the above-mentioned delay time td and sampling pulse S
The relationship until Pl and S P 2 are formed will be further explained in detail with reference to FIG. 1θ.

In both periods tB and tA, as shown in FIG.
A pair of pulses Pi (corresponding to the beginning of P A4 + P A11 in Fig. E) after a delay time td elapses from the signal Ss (Fig.
), the first pulse pH lasts for a time t1, and after a time to, a second pulse P12 similarly lasts for a time tl. and the first pulse 2
Sampling pulse 5Pz at the falling edge of the mouth (Fig. 10D)
) is generated, and a sampling pulse 5P2 (FIG. 10E) is generated at the falling edge of the second pulse PI2. Note that the delay time td at this time is as described above (t 1 =
−t p, the pulse P obtained in this way
i is supplied to the peak hold circuit (21), and sampling pulses S P 1 and SF3 formed based on this pulse Pi are supplied to the sampling bold circuits (22) and (24), respectively.

Therefore, the head (IB) has tracks (5B2) and (5B2).
The dashed line To in Figure 3 spans the two tracks of ^2).
As is clear from FIGS. 9 and 10, during scanning in the direction shown in FIG. (5B2) The crosstalk of the pilot signal PA4 of > is peak bolded in the peak hold circuit (21), and the peak hold circuit (21) at this time
The output of is supplied to the sampling hold circuit (22), where it is sampled by the sampling pulse SP1 generated at the falling edge of the first pulse Ph, and is sent to one of the differential amplifiers (23) as a tracking signal with a delayed phase. Supplied to the input end.

Further, the second pulse PL2 of the pulse Pi is the pilot signal P of the track (582) on the opposite side to the tape transport direction.
'B4 crosstalk is peak-held in the peak-hold circuit (21), and the output of the peak-hold circuit (21) at this time goes to the other input terminal of the differential amplifier (23) and is supplied as a phase tracking signal. be done. Therefore, the differential amplifier (23) compares the tracking signals corresponding to the crosstalk of the pilot signals PA4 and PH1, respectively. The comparison error signal from the differential amplifier (23) is then supplied to the sampling hold circuit (24), where it is sampled by the sampling pulse SP2 generated at the falling edge of the second pulse PI2.

Therefore, from this sampling and hold circuit (24), the difference in the power applied to the differential amplifier (23) is obtained as a tracking control signal, and this is supplied from the output terminal (25) to the capstan motor (not shown) to tape the tape. The amount of transfer of the head (IB) to the track (5
When scanning over the two tracks 112) and (5A4), the rotary head is controlled so as to draw a scanning locus as shown by the broken line To.

In addition, the same procedure is applied to other tracks (1). For example, two tracks (583) and (583) are attached to the head (IA) in the direction shown by the broken line To in FIG.
When scanning, in the area AT shown in the figure, the pilot signal '4 F AT of the truck (51h),
Pilot signal PB of trucks on both sides (5^3)? and the pilot signal PB2 of the trunk (5A2), and in the area AT8, the pilot signal PA11 of the truck (5Bm) and the pilot signal pea of the adjacent truck (5A3) are reproduced. The pilot signal Pu2 of the truck (584) on both sides of (5A3), the pilot signal PA11 of the truck (5B3), and the pyro signal of the truck (5Δ3)
The throat signal PB11 is generated.

Therefore, during this period IA, a regenerated output of the pilot signal as shown in the right 1 minute of FIG.
).

It was also played from the center of the track. <Of the pilot signals PAII and PRll, the scanning direction force) is the signal 88 that is substantially obtained by the detection of the frontmost pilot signal PAe based on 89, and the right side of FIG. 9I). A pair of palls Pl during the period IA as shown in
FIG. 9 J and K generated at the falling edge of this pulse Pi
A sword-like lanpring pulse SP1 is on the right side of the
and SF3, and using these, pyro・
By comparing each tire knock signal corresponding to the crosstalk between the throat signal PAIL and PBs, a tire knock control number 1 for the head (IA) can be obtained.

In addition, in the same way, the head (113) is
When scanning in the direction shown by the broken line 'ro in Figure 3, the force is recorded in the center part (area ATE) of the two tracks B4) and (5^4). Pilot signals PAlo and PBlo, also head (18)
When scanning in the direction shown by the broken line TD in the same figure across two tracks (5Bs) and (5^5), the pilot recorded in the center part (area ΔT8) PA1s and Pa□6 are extracted with sampling pulses SPt and SF3, respectively, and the pilot signal P
A tracking control signal for the head (IB) is obtained by comparing the tracking signals corresponding to the crosstalk of A10 and PE110, and a tracking control signal for the head (Ill) is obtained by comparing the tracking signals corresponding to the pilot signal PA15 and Pets. Just try to get it.

Also, when playing at 3x speed, adjacent tracks (5x
/l) Even if (5B) have different azimuth angles, the rotating heads (IA) and (IB) scan alternately at a three-track pitch, so the heads scan tracks with different azimuths as in the case of double speed. °. Therefore, in this example, the central area AT3 is used to control the rotary head so that it draws a scanning locus as shown by the two-dot chain line TT in FIG.

Now, for example, the head (IB) is indicated by the two-dot chain line 1 in Fig. 3.
Assuming that a range of scanning width W including a track (5B2) as shown in FIG.
As shown in FIG. 3, in the area AT1, the pilot signal PA2 of the truck (582), the pilot signal PB2 of the trunk (582) on both sides, and the pilot signal of the truck (5Ai) are scanned across the area AT1. The signal Pal is reproduced, and in the area A T@, the track (
5B2) pilot signal PA4, and the pilot signal P84 of the adjacent truck 5^2) and the trunk (57h
) is reproduced, and in area AT2, the pilot signal PAe of track (5B2) is reproduced.
Pilot signal PB6 of trucks on both sides (5A2)
and the pilot signal PBs of the trunk (5^1). At this time, from the switch circuit (19) to the ρ head (
The reproduced output of IB) is supplied to a narrow band band pass filter (20) with a passing center frequency f1, and as shown in Figure 11, only the pilot signal is taken out as the output SF, which is passed through a peak hold circuit (21). ).

Further, the output SF of the band pass filter (20) is shaped into a rectangular wave by the waveform shaping circuit (26) as described above, and then supplied to the delay circuit (27), so that the rear part thereof is substantially shaped into a rectangular waveform for a predetermined time tI11. A signal J+S v similar to that shown in FIG. 11E delayed by 1 is obtained. This signal S7 is supplied to detection circuits (28) and (29), which detect its rise and fall, respectively, and as in normal playback,
During the period te during scanning with the head (IB), the detection circuit (2
8) The rising edge of the signal S7 detected in the switch circuit (
It is supplied to the gate circuits (331) to (33s) through the contact a side of the switch circuit (30) and the contact side of the switch circuit (31), while during the period LA during scanning with the head (1^), the detection circuit ( The falling edge of the signal S7 detected in 29) contacts the switch circuit (30) and the switch circuit' (31
) through the contact side of the gate circuit (331”) to (33
s).

Furthermore, during triple speed playback, the window signal generating circuit (34) generates wind signals SW2 and SW4 as shown in FIG. 11B-C in response to a setting instruction signal from the output terminal X3 of the mode setting circuit (32). The gate circuit (33
2) and (334) as gate signals. Therefore, only the rising and falling edges of the signal S7 that entered during each period of the window signals Sν2 and 8w4 are actually sent to the output side of these gate circuits. As a result, as shown in FIG. matches,
During the period tA, a narrow signal S8 that coincides with the falling edge of the signal S7 is obtained.

This signal S8 is supplied to a delay circuit (36).

Also, at this time, the delay time setting circuits (38) and (40) are selected in the selector (37), and the delay times ta and t are selected.
c is set for the slow slope circuit (36).

During the period LB, the delay circuit (36) generates a signal S9 delayed by a time ta from the signal S8, as shown on the left side of Figure 5, and during the period tA, as shown on the right side of Figure 11G. As shown, a signal S11 delayed by a time tc from the signal S3 is generated.

This signal S9 is supplied to a pulse generation circuit (43), where a pair of pulses Pi corresponding to each pilot signal to be detected is formed as shown in FIG. 11H based on the signal Ss, and a sampling pulse Generation circuit (44)
and is supplied to the peak hold circuit (21). Based on the pair of pulses Pi, the sampling pulse generation circuit (44) generates sampling pulses SPi and SF3 as shown in FIG. 24).

Here, the delay times La and tc are set in the same manner as in the normal playback described above.

The pulse Pi thus obtained is supplied to the peak hold circuit (21), and the sampling pulses SP1 and SF3 formed based on this pulse P1 are supplied to the sampling and hold circuits (22) and (24), respectively. That will happen.

Therefore, while the head (IB) is scanning the track (582), as is clear from FIG. is the peak hold circuit (21) for the crosstalk of the pilot signal PB4 of the adjacent track (5^2) on the opposite side.
The output of the peak hold circuit (21) at this time is supplied to the sampling hold circuit (22), where it is sampled by the sampling pulse SP1 generated at the falling edge of the first pulse pH. , is supplied to one input terminal of the differential amplifier (23) as a leading phase tracking signal.

Further, the second pulse Pt2 of the pulse Pi is the pilot signal PBI of the adjacent track (5Δ1) on the tape transport direction side.
The crosstalk of I is held at its peak in the peak hold circuit (21), and the output of the peak hold circuit (21) at this time is supplied to the other input terminal of the differential amplifier (23) as a tracking signal with a delayed phase. be done. Therefore, the differential amplifier (23) uses the pilot signal P
The tracking signals corresponding to the crosstalk of B4 and pea are compared. The comparison error signal from the differential amplifier (23) is then supplied to the sampling and hold circuit (24), where it is sampled by the sampling pulse SP2 generated at the falling edge of the second pulse PL2.

Therefore, from this sampling and hold circuit (24), the difference in the power applied to the differential amplifier (23) is obtained as a tracking control signal, and this is supplied from the output terminal (25) to the capstan motor (not shown) to tape the tape. The transfer amount of the head (IB) is controlled so that the level difference between the two inputs to the differential amplifier (23) is zero, that is, the head (IB) is moved to the position shown in FIG. Control is performed to draw a scanning locus as shown by the dotted chain line TT.

The same process is applied to other tracks, for example, the track (5B2) that is three tracks after the track (5B2).
When the head (1^) scans 3) as indicated by the two-dot chain line in Figure 3, as shown on the right side of Figure 11,
Truck (5^3) pilot signal Pa1l PB8
1 Pilot signals PAll+PA1o of PBll and the trucks (5B4) and (5B3) on both sides thereof,
Since the crosstalk of PA12 and PATI PAs + PAtx can be obtained, the adjacent tracks (5
The crosstalk of the pilot signals PA10 and PAII recorded in the central area ATs) of B4) and (5B3) is sequentially peak-held by the peak hold circuit (21), and then the sampling pulse generation circuit (44) is connected to the sampling hold circuit. (22) A tracking signal is obtained by sampling the crosstalk of 1c to the pilot signal P using the sampling pulse SP1 supplied to
This is supplied to the next-stage differential amplifier (23), and the output from the peak hold circuit (21) corresponding to the crosstalk of the pilot signal PM is supplied. A tracking control signal for the head (1/l) can be obtained by comparing the tracking signals corresponding to each talk and sampling the comparison error signal with the sampling pulse SP2 supplied to the sampling hold circuit (24). .

Also, in the same way, move the track (585) to the head (IB).
When scanning in the direction shown by the two-dot chain line T'T in Fig. 3, the tracks (5^6) and (5
Since the crosstalk of pilot signal P+31a and peto in the central part (area ATTl) of A4) can be obtained, the crosstalk of pilot signal PBXS is sampled with sampling pulse SP1, and
), the tracking signals corresponding to the crosstalk of the pilot signal P15 and PBLO are compared, and the comparison error f is finally sampled with the sampling pulse SP2, thereby generating a tracking control signal for the head (IB). can be obtained.

As described above, in this embodiment, during playback, the pilot signal is detected substantially based on the starting edge of the playback output of the pilot signal recorded on the track, and the sampling pulse is self-generated. Since the self clock is generated substantially from the track pattern, the pulse PC such as offset
There are no negative effects when using this as a standard.

In addition, a sampling pulse is generated as described above during each scanning period of each head to detect the tracking/knocking position.
In other words, each head generates a self-clock as a sampling pulse each time on the track pattern, and detects the track/knocking position for each track.
The effect of jitter is also eliminated.

Furthermore, in each reproduction mode, the detection position of the pyro-nod signal can be changed by substantially changing the delay time from the edge, so most of the circuit configuration can be made common.

In addition, in the above-mentioned embodiment, the variable speed playback is 2x speed or 3x speed.
The present invention is not limited to double speed playback, and can be similarly applied as long as the playback speed is an integral multiple.

In addition, although the above-mentioned embodiment is a special rotary head device that records and reproduces tape by winding it over an angular range narrower than the head angular interval, the tape is wound around the angular range that is the same as the head angular interval as usual. Of course, the present invention can also be applied to the case where a rotary head device is used for winding the material.

Effects of the Invention As described above, according to the present invention, when a recording trunk is scanned by a rotary head, a pulse signal for detecting the pilot signal recorded on the track is formed based on the reproduction output of the pilot signal, and the pulse signal is detected. Since the tracking control signal based on the detection output is used to control the tracking of the rotary head during normal playback or variable speed playback such as double speed or triple speed, the device is free from mechanical changes over time, temperature changes, or jitter. Tracking control during normal playback or variable speed playback can be performed with high precision even if the device used during playback and recording is different from that during playback, without being affected by any such effects, thereby ensuring compatibility between devices. be able to. Furthermore, when the playback speed changes, it is only necessary to selectively switch the delay setting time and change the detection position of the pilot signal, so it is possible to standardize the circuit in a playback system that can change substantially different playback speeds. be able to.

[Brief explanation of the drawing]

FIG. 1 is a circuit configuration diagram showing an embodiment of the present invention, FIG. 2 is a diagram showing an example of the rotary head device used in FIG. 1,
3 is a diagram showing an outline of the recording trunk pattern of the present invention, FIG. 4 is a signal waveform diagram for explaining the recording operation in FIG. 1, and FIG. 5 is a diagram for explaining the normal playback operation in FIG. 1. 6 to 8 are signal waveform diagrams showing each part of FIG. 5 enlarged, and FIG. 9 is a signal waveform diagram to explain the double speed playback operation in FIG. 1. 10 is a signal waveform diagram showing an enlarged part of FIG. 9, and FIG. 11 is a signal waveform diagram for explaining the triple speed reproduction operation in FIG. (IAC (IB) pot rotating magnetic head, (2) is a magnetic tape, (6) is a pilot signal oscillator, (7) is a recording waveform generation circuit, (8) is an edge detection circuit, (16), (
17). (27), (36) are delay circuits, (20) are band pass filters, (21) are peak hold circuits, (22)
. (24) is a sampling bold circuit, (23) is a differential amplifier, (26) is a waveform shaping circuit, (28) is a rising detection circuit, (29) is a falling detection circuit, (32) is a mode setting circuit, ( 331) to (33s) are gate circuits,
(34) is a window signal generation circuit, (37) is a delay time setting selector, (38) to (41) are delay time setting circuits,
(43) is a pulse generation circuit, and (44) is a sampling pulse generation circuit. r

Claims (1)

[Claims] In a method for compressing the time axis of a digital signal, forming and recording a diagonal trunk on a recording medium using a plurality of rotary heads without forming a guard band, and reproducing this, the What is a digital signal? A plurality of tracking pilot signals are recorded independently as a recording area, and during playback, when the recording trunk is scanned by a rotating head whose scanning width is wider than the width of the track, during the first scanning period. A pulse signal is formed based on the self-reproduction output of the pilot signal recorded on the currently scanned track, and during the second scanning period, the pulse signal is generated based on the self-reproduction output of the pilot signal recorded on the currently scanned track. A pulse signal is formed based on the reproduction output of the previous pilot signal, and during the period of each of these pulse signals, the pilot signal is detected from the adjacent track being scanned by the rotary head, and the detected output is used to detect the above-mentioned pilot signal. A method for recording and reproducing digital signals, characterized in that tracking control of a rotating head is performed.