JPS60164944A - Slow tracking device of magnetic recording and reproducing device - Google Patents

Abstract

PURPOSE:To attain ease of handling by automating the tracking adjustment at fine slow so as to eliminate the need for a tracking adjusting variable resistor thereby eliminating the need for tracking adjustment at fine slow having been required at each cassette replacement. CONSTITUTION:After a tape 1 is moved by one frame by means of a start/stop control means 19, a noise position is detected so as to set a delay amount of a tracking delay means 17 at the next operation. Thus, when the tape 1 is moved by one frame's share by means of the start/stop control means 19, the stop timing is decided by the said set delay amount and the noise position approaches the vertical blanking period. The noise position is detected again and the delay amount of the tracking delay means 17 for the next operation is reset again. Thus, the noise position approaches the vertical blanking period further and becomes in the stop state after the next frame feeding. It is possible to drive the noise position to the vertical blanking period by repeating the operation above for several times.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application] The present invention relates to fine throw control of a magnetic recording/reproducing device, and relates to an automatic control aI device suitable for 1% I/c (so-) racking.

[°Background of the invention]

Looking at conventional fine slot temporary tracking methods, they are all done by hand! Since it required 7 operations, it was necessary to operate the slow tracking adjustment every time the cassette chip was replaced and fine slow playback was performed, which was very inconvenient. Furthermore, the adjustment volume for throat tracking is generally installed in the remote control box, which has the disadvantage of increasing the amount of wiring between the main unit and the remote control.

[Purpose of the invention]

The purpose of this book @ Ming was to automate the fine-throw temporary tracking adjustment in order to eliminate the drawbacks of the above-mentioned conventional technology. The present invention provides a slow tracking device for a magnetic recording/reproducing device.

[Summary of the invention]

The main focus of the present invention is to detect the position of noise in the playback screen during fine slotting, automatically control the amount of tracking delay so that this noise position is driven outside of the five-stroke area, and perform this eye movement tracking operation. After repeating this several times, the automatic tracking function stops.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to FIG. 1st
In the figure, c1 is a magnetic tape, 2&! Cagstan motor, 6 a drive amplifier, 4 speed control means, 5 a switch,
6 is the cylinder motor.

7 is speed phase control means; 8 is cylinder phase detection means;
9 is a waveform shaping circuit, and 10 is a video head.

11 is a signal processing circuit, and 12 is a control head.

13 is an amplification waveform shaping circuit, 14 is a fine throw control means 14, and this fine throw control means 14 is a frequency dividing circuit 15. Delay means 16. Tracking delay means 17. Delay control means 18. It is composed of a start/stop control means 19. Further, the delay control means 18 includes a noise detection circuit 20.
It is composed of noise position automatic control means 21.

I will explain the operation shortly. 1. During normal playback, the cylinder motor 6 rotates at a single speed by the ten-stage speed phase control 7, and is controlled at a predetermined phase with respect to a reference signal (not shown).
iA is moving again. - The million-cargustan motor 2 is rotated at a single speed by the speed control means 4 via the drive ann 13, and is controlled at a predetermined phase with respect to the reference signal by a one-phase control means y (not shown). Now, when the slow tiI'δ signal is input manually, the Cag stan motor 2 temporarily stops. Thereafter, the cab stan motor 2 is repeatedly started and stopped by the switch 5 and the fine throw control means 14.

Tape 1 is fed 1M4 intermittently. Here, three signals are input to the fine throw control means 14 in addition to the slow phasing signal. The rotational phase of the double-cased cylinder motor 6 is detected by the phase detection means 8, and the waveform shaping circuit 9
The head control signals (hereinafter referred to as MS signals) obtained by A control signal (hereinafter abbreviated as CTL signal) obtained from VC is reproduced by head 12 and input manually. To explain the operation with reference to FIG. 2, the switch 5 is once opened with the manual force of the slow command, and the cab stan motor 2 is temporarily stopped. The switch 5 opens and closes, and the carburetor stan motor 2 repeats starting and stopping, and the tape 1 is intermittently fed by 1Mj each frame.

This situation is shown in Figure 2. First, each BS issue has frequency divider circuit 1.
The frequency is divided appropriately from 51C. The delay means 16 is triggered by this frequency-divided output (FIG. 2 (2)), and the start timing of the cab stan motor 2 is determined by this delayed ground weight. Output of the restart dog control I41 means 19 (Fig. 2 (4))
is the falling edge of the output of the delay means 16, and BI and r(-ri,
Close switch 5. As a result, the cab stun 2 is activated and the tape 1 begins to move. Thereafter, when the first CTL signal is detected by the control head 12.

The tracking delay means 17 is fed with the CTL multiplied signal. The delay amount of the delay means 17 determines the stop timing of the cab stan motor 2, and the opening/opening signal of the switch 5 (FIG. 2 (41) falls to L°. This is done once every cycle.

In the above operation, the delay amount of the delay means 16 is as follows.

This determines the timing for starting the movement of the tape 1. This timing is set to 1 tatami to prevent noise from occurring when the tape is moved.On the other hand, the tracking delay means 1
The delay amount 7 determines the stop timing of the tape 1, that is, the stop position. By changing this stop timing, the stop position of the tape can be changed, and the noise position at the time of a steal can be changed.

The above operation will be explained with reference to FIG. FIG. 6 is a graph showing the recording cheat pattern and the trace state of the head during reproduction. For a detailed view of this graph, see Reference 11.
．． 2 others: 1 Analysis method for VTR track batters 2 TV Society 9MR80-8 (1980-9)" Detailed explanation will be omitted. The state in which the playback trace band is parallel to the horizontal axis is The state parallel to the diagonal crossbar indicates the stopped state, and the state parallel to the slope indicates the operation regeneration state.Status A is the state in which the fine throw motion is performed by the regular participant.In other words, during normal regeneration operation, the regeneration trace state is not achieved. , it exactly matches the diagonal section, and no interpolation noise occurs.The playback trace state also perfectly matches the horizontal section, and the tape stop position after feeding the reed tape perfectly matches the horizontal section, and still playback without bar noise occurs. It becomes. In other words, it is in a just tracking state and has noiseless still playback.

Next, state gB shows a state in which tracking is shifted when the delay cover of the tracking delay means 17 is shortened. At this time, the tape stop position after the tape is fed is either in poor trace condition or slightly deviated from the horizontal axis section, causing tracking to deviate and noise to be generated. If you repeat fine throw in this state, the result will always be a noisy Smee image.

Therefore, in the practical example shown in FIG. 1, noise is detected in the noise detection circuit 20 using the output of the Shinshun processing circuit 11. This noise detection signal is applied to the next stage automatic noise position control means 21, and compared with the BS signal to detect the °C noise position. This noise position output # control means 21 detects [5
The amount of delay of the tracking delay means 17 is controlled according to the noise level it. This control force method assumes that the tape 1 is moved eight times per frame by the start strafe' control means 19, and the noise position is used to track i! during the first movement. The delay lid of the A delay means 17 is set.

'1: Next, when the tape 1 is moved by one frame by the start strut 7" moving means 19, the stop timing is determined by the set delay, and the % noise position is at the vertical storage stage. Get closer.

Here, the reset noise position is output and the delay amount of the tracking delay means 17 is reset for the next operation. Therefore, after the next frame is sent, the noise position approaches the vertical return period and stops at 4K. By repeating the above operation several times, it is possible to bring the noise position closer to the vertical #period VC.

The above explanation describes the basic operation of the noise position automatic control means 210, and a first-order detailed embodiment is shown in FIG. In the figure, 22 is a doubler circuit, 26 is a gate signal generation circuit, 24 and 25 are latch circuits, 26 is a pulse generation circuit, 27 is an up/down counter, 28 is an AND gate, and 29 is a switch. Out J! 21 ff+IJ wholesale means 21 is constructed. On the other hand, the output of the up/down counter 27 is applied to the tracking delay means 17 at the next stage. This delaying means 17 includes a flip 70 knob 60 (hereinafter abbreviated as FF), a delay counter 31 . It is composed of a count value detector 52.

Next, the operation will be explained using FIG. First, head SW
The signal (Its signal) is transformed by the doubler circuit 22 into the signal shown at the peak in FIG. In other words, the BS signal falls at each etch, resulting in a signal whose periods of .degree.B" level and L" level are approximately equal. On the other hand, the gate signal generation circuit 23 outputs a gate signal having a pulse width (L level) corresponding to the interval between the two etches of the BS signal. Both of these signals are input to the take terminals of latch circuits 24 and 25 in the next stage.

The noise signal is also input to the pulse generating circuit 26 via the switch 29, and this circuit outputs a launch pulse L and a clock pulse C one after another.

The latch pulse L causes the latch circuits 24 and 25 to take in the take. Here, the output of the latch circuit 24 is:

The up/down end of the next stage up/down counter 27 (U/
I) and determines the mode of the counter 27. The output of the latch circuit 25 is connected to the AIVD gate 28 and gates the clock pulse C from the pulse generation circuit 26. The output of this AND gate 28 is input to the trigger end (T end) of the primary stage up/down counter 27. In other words, like α and b of the noise signal (4) in Figure 5,
If a noise signal is input manually while the output of the gate signal generation circuit 23 is at the °B level, the output of the latch circuit 25 becomes 6B', the AIV'D gate 28 passes through the axhars C, and the noise signal In the case of C in (4), the clock pulse C is not passed. In other words, in this state C, the up/down counter 27 does not operate and its count information does not change. This up/down counter 270 count information is next to the preset value of the delay counter 31 of the primary stage tracking delay means 17.

The operation of the trunking delay means 17 will now be explained with reference to FIG. First, as an initial state, -(pF50 is set, its output is 1)il, and the delay counter 61 is in a reset state. At this time, the output of the count value detector 32 is at the °L" level.

Now, when a control signal (CTL signal) is input, F
F50 is inverted and the delay counter 31 releases the preset and starts counting clock inputs. Thereafter, when the count value is counted until it is equal to the set value of the count value detector 32, the output of the count value detector 32 is inverted to WGA, and the FF 50 is set. Therefore, the output is as shown in FIG. 6 (2).

Now suppose that the noise signal is in the α state shown in FIG. 5 (4). At this time, the Uρ multiplied signal is L", and the up-down counter 27 is in the down mode. Therefore, the up-down counter 27 increases its count value by one by the clock pulse C from the pulse generation circuit 26 that is generated immediately after the noise signal. As a result, the preset value of the next stage delay counter 61 changes from 7v1 to (3) as shown in FIG.
Changes to N2<Pano. Here, the count value detector 620 is set to the state where each bit output is "H", that is, (2rL
-1, the operation of the delay counter 31 is as shown in Figure 6 (3).
) becomes longer. That is, as shown in FIGS. 1 and 2, as the delay amount of the tracking delay means 17 becomes longer, the timing at which the tape 1 stops becomes later. In other words, as the state B approaches state A in FIG. 3, the noise position becomes the state shown in FIG. The count value becomes even smaller, and the delay lid of the tracking delay means 17 becomes longer rL. As a result, the position of the noise signal becomes state C in FIG. 5(4), and is forced into the vertical retrace period. In this state, as explained above, the output of the latch circuit 25 becomes rL6, and the passage of the clock pulse C is stopped. In other words, the up/down counter 27 stops counting and holds count information.

Regarding the operation of the switch 29, during the period when the tape 1 is being driven, the noise position moves by one frame 3. If the information of the H5 signal is latched during this period, it is likely to malfunction. For.

Only one cycle of the H5 signal is sufficient for the period 114j in which the switch 29 is closed, which is provided to prohibit the input of noise signals.

In the above configuration, when the noise position is not pushed into the vertical return period, the noise position only changes by the amount of delay time change that is sufficient for one reset of the delay counter 61.

In other words, if the noise position is located at the center of the screen, a slightly larger number of fines a is required to penetrate the noise Xm.

FIG. 7 shows an embodiment in which the noise can be chased away with one fine throw operation regardless of the position of the noise. In the figure, 'c53 is an FF, 34 is a pulse generation circuit, 65 is an IMI difference counter, 36 is a latch group, and 37
68 is a successive adder, 68 is a switch, and the other parts are the same as in FIG. In FIG. 7, switches 29 and 58 are closed only for one period of the IiS signal when there is no tape movement.

In the initial state, the FF531 time difference counter 35. Successive adder 67 is in a reset state. To explain the operation using FIG.
The ND gate 28 is opened to supply a clock signal, and the one-time difference counter 35 starts counting. Thereafter, the rising edge of the signal obtained by doubling the H5 signal is output from the doubling circuit 22.

FF55 is tri-inputted and its output is inverted to @L1.

The time difference counter 65 stops counting. On the other hand, the pulse generating circuit 34 first outputs a latch pulse L and then a reset pulse R in response to the rising edge of the doubled signal.

This latch pulse L causes the count information of the time difference counter 65 to be taken into the latch group 36, and the reset pulse R causes the time difference counter 35 to be reset. At the same time, this reset pulse () is also applied to the addition command trigger terminal T'[ of the sequential adder 67, and is increased only - times.

The operation of the successive adder 37 is to manually add the held information and theta input and hold the added information.

The output of this successive adder 57 is the output of the delay counter 61 of the next-stage tracking delay means 17 as in FIG.
Dimension 11. However, in order to match the direction of change of the delay lid, the output of the successive adder 37 in FIG. 8 F71 is shown as a negative phase output.

In the above operation, ℃ directly measures the time difference between the noise signal and the first delay correction period (etched part of both HE double signals), and only the amount commensurate with this il measurement 1. , the Bricella l' 1ilt of the next-stage delay counter 31 is corrected. At the time of one movement of the first 7-fine throw,
The noise position rapidly approaches the vertical retrace period. Any subsequent slight positional deviation will be corrected to almost the original amount by the primary delay and correction, and the noise will be eliminated. Of course, once the noise reduction is completed, switch 29 above
, 58 or to stop the operation of the automatic noise position control means 21.

〔Effect of the invention〕

According to the present invention, since the fine slot temporary tracking adjustment can be automated, there is no need for a tracking adjustment volume, and there is no need for the fine slot temporary adjustment that is necessary every time a cassette is replaced, making it easy to use. ＞
Both have the effect of being able to reduce the number of losses due to remote control.

[Brief explanation of the drawing]

Figure 1 shows the circuit diagram of one embodiment of the present invention, and Figure 2 shows the circuit diagram of the first embodiment of the present invention.
FIG. 4 is a waveform diagram of main parts for explaining the operation in the figure. Figure 3 is a track trace diagram of a temporary fine slot, Figure 4
The figures are circuit diagrams showing other embodiments of the present invention, Figures 5 and 6.
7 is a circuit diagram showing still another embodiment of the present invention, and FIG. 8 is a waveform diagram of the main part of FIG. 7. 14...7 Ains a-control means 15...branch circuit 16...delay means 17...tracking delay means 18...delay control means 20...noise detection circuit 21...noise position automatic Patent Attorney for Control Means Akio Taka Taka

Claims (1)

[Claims] t Playback is performed by repeating one frame forwarding and still forwarding. A magnetic recording and reproducing apparatus capable of so-called fine a-reproduction includes a noise detection means during fine slow reproduction, a tracking delay means, and a signal generation means corresponding to the vertical #gland period, and the noise of the noise detection means is 1. A slow tracking device for a magnetic recording and reproducing device, comprising automatic delay control means for controlling the tracking delay means by detecting a time difference between the signal and the vertical box return period signal. 2. The odor temperature as described in claim 1. A slow tracking device for a magnetic recording/reproducing device, characterized in that when the setting of the delay amount is completed by the automatic delay control means, the function of the automatic delay control means is stopped.