JPS63217573A - Recording and reproducing device for digital signal - Google Patents

Abstract

PURPOSE:To speedily copy by delaying reproduced signals for a prescribed time, detecting ATF patterns during that time and controlling the recording level of specified signals included for a period while a timing pulse is supplied. CONSTITUTION:A recorded magnetic tape 12 is reproduced and amplified 2, and the reproduced signals are obtained from the output of a PLL 3 and are outputted through a decoder 4, a D/A 5, an LPF 6 and a buffer amplifier 7, whereby they are monitored. On the other hand, an ATF detection circuit 11 detects the ATF patterns in the reproduced signals and generates a pulse showing the start. A timing generation circuit 12 processes a detection time which the circuit 11 needs and a delay time (t) in a delay circuit 13 based on the pulse, generates the timing pulse in a period equivalent to pilot signals f1 in the ATF patterns and supplies them to a level control circuit 14. Said circuit 14 level-controls the recording level of the signals f1 for the timing pulse period and records them on a magnetic tape 10 through a recording amplifier 9. With this constitution, signals with adverse erasing characteristics such as the signals f1 can be recorded at a low level and speedy copy by direct recording can be executed.

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to an apparatus for recording an audio PCM signal on a magnetic tape using a rotating head in one diagonal track for each unit time, and for reproducing the same. In particular, the present invention relates to a digital signal recording and reproducing apparatus that copies a recorded tape onto another tape while reproducing it.

[Technical background of the invention and its problems] A case in which an audio signal is recorded on a magnetic tape by forming one diagonal track every unit time using a helical scan type rotary head, and is then played back. R-DAT (rotary head digital audio tape recorder) is a device that converts audio signals into PCM and records and reproduces them.
The development of a magnetic recording and reproducing device called .

Conventionally, as this type of device, one having the configuration shown in FIG. 4 has been considered.

1 on the rotating drum II in the mechanism block 1 on the playback side.
Two heads A and B mounted at an angular interval of 80° rotate the rotating drum 1. The RF flaw signal is pick-amplified from a recorded magnetic tape 1t which is wrapped in a 90° angular range along the circumferential surface of the tape and runs at a predetermined speed. is supplied to

Data is extracted from the reproduced signal by the PLL circuit 3, and based on the data, the decoder 4 performs error correction, dinterleave, etc. as processing during reproduction.

The digital signal subjected to the above-described processing during playback by the decoder 4 is converted into an analog signal by the D/A converter 5, and only the analog signal component included in the original signal is extracted by the low-pass filter 6. It is output from the output terminal T,1 via the amplifier 7.

On the other hand, the reproduction signal from the decoder 4 described above is supplied to the encoder 8 which performs processing for copying. Then, the encoder 8 adds interleave and parity signals again according to the format specified by R-DAT as recording processing to the signal subjected to error correction and dinterleaving by the decoder 4, and then the recording amplifier 9. The signal amplified at the optimum level by the recording amplifier 9 is sent to a mechanism block 10 on the recording side.
Rotating drum inside 10. The information is recorded on the magnetic tape 10t by two heads A and B mounted on the magnetic tape 10t, and information reproduced from the recorded magnetic tape 1□ is copied onto the magnetic tape 10□.

Furthermore, in the configuration shown in FIG. 5, the reproduced signal from the PLL circuit 3 is directly supplied to the recording amplifier 9 for recording, and no error correction or the like is performed on the reproduced signal. The configuration is such that it can be directly copied to the .

Conventionally, copying is performed based on the configuration described above, so when performing high-speed copying with the configuration shown in Figure 4, error correction may not be done in time, or the configuration shown in Figure 5 Even if the recording to the PCM area on the recording format is successful, the ATF signal for tracking is recorded at a low frequency.
There was a problem that recording to area F could not be performed normally.

In particular, there is a problem in that the recording level of the 130 KHz pilot signal in the ATF signal cannot be controlled, even though its frequency is significantly different from other signals.

[Purpose of the invention]

The present invention was made in order to eliminate the above-mentioned problems in the conventional art.The present invention delays the reproduced signal by a certain period of time, detects the ATF pattern during this time, and detects the ATF pattern.
It is an object of the present invention to provide a digital signal recording and reproducing device that can control the recording level of a specific signal recorded in an F pattern and also generate and copy a signal corresponding to the specific signal.

[Summary of the invention]

The present invention provides a ΔTF detection circuit that detects an ATF pattern from a reproduced signal obtained by reproducing a recorded tape, and a timing that indicates a specific signal period in the ATF pattern based on the detection output of this ATF detection circuit. A timing generation circuit that generates a pulse, a delay circuit that delays the reproduction signal by a certain period of time necessary for detection by the ATF detection circuit, and a period during which the timing pulse from the timing generation circuit is supplied. A recording level control circuit for controlling the recording level of a reproduced signal delayed by a certain period of time by the above-mentioned delay circuit is provided, so that the recording level of a specific signal recorded in the ATF pattern can be controlled. .

Furthermore, in addition to the above configuration, there is also a switch that switches the signal supplied to the recording amplifier from the output of the delay circuit to the output of the recording level control circuit only during the period when the timing pulse from the timing generation circuit is supplied, and an ATF for the reproduction signal. and a signal generator that generates a signal corresponding to a specific signal recorded in the pattern and supplies it to the recording level control circuit,
The recording level of the specific signal recorded in the ATF pattern can be controlled, and the correct signal from the signal generator can be recorded instead of the reproduced specific signal.

〔Example〕

Hereinafter, embodiments according to the present invention will be described based on the drawings.

FIG. 1 is a block diagram showing an embodiment of the present invention. Note that parts equivalent to those in FIGS. 4 and 5 are denoted by the same reference numerals, and detailed explanation thereof will be omitted.

In the figure, 11 is an ATF detection circuit that detects an ATF pattern from the reproduced signal supplied via the PLL circuit 3, and 12 is a specific signal present in the ATF pattern detected by the ATF detection circuit 11, such as a pilot signal period. This is a timing generation circuit that generates a timing pulse indicating .

13 converts the reproduction signal supplied from the PLL circuit 3 into the above A
In the TF detection circuit 11, a delay circuit delays the detection of the ATF pattern by a certain period of time, and 14 is a recording level control circuit for controlling the recording level of the recording signal.

Next, a copy operation in the apparatus having the above configuration will be explained with reference to the flowchart shown in FIG. In FIG. 3, (a) is a frame pulse indicating the periods of odd and even trunks, (bl is a head switching pulse indicating switching between heads A and B, and (C1 is a head switching pulse indicating head A, head B switching).
Each of B is a head touch detection pulse indicating a period in which the head is in contact with the magnetic tape.

When the recorded magnetic tape 1□ is played back by the mechanism block 1 on the playback side, the signal from the magnetic tape 12 is transmitted to the rotating drum 1. is picked up alternately by two heads A and B mounted on the
Data is extracted by being supplied to the L circuit 3, and the PLL
A reproduced signal shown in FIG. 3(d) is obtained from the output of the circuit 3. The data structure of this reproduced signal is MA at the beginning.
13 blocks including RG IN and PLL, 5UB-1,
5UB-2 has 8 blocks each, PO3T AMBLE has 1 block, IBG (Inter Block
Gap) is 3 blocks each, PLL is 2 blocks each,
PCM is 128 blocks, PO3T A at the end
12 blocks including MBLE and MARGIN, total 196
It is made up of blocks.

As described above, the reproduced signal from the PLL circuit 3 is outputted from the output terminal T out via the decoder 4, the D/A converter 5, the low-pass filter 6, and the buffer amplifier 7, and is monitored as appropriate.

On the other hand, the above-mentioned reproduction signal from the PLL circuit 3 is
The lateral output circuit 11 is supplied to the extension circuit 13.

The ATF detection circuit 11 detects the ATF pattern in the reproduced signal (or the IBG immediately before the ATF pattern).
part) and indicates the beginning of the ATF pattern.
Outputs the pulse shown in the figure (el).

The above ATF pattern has a 130KHz pilot signal f+, a 522KHz sync signal fz (784K
Hz sink signal f+), 1.56 MHz erase signal f
It consists of 4 combinations.

The timing generation circuit 12 subtracts the time required for detection in the ATF detection circuit 11 and the delay time t in the delay circuit 13 based on the above-mentioned output from the ATF detection circuit 11, and calculates the biloft signal f in the ATF pattern. A timing pulse shown in FIG. 3(g) is generated during a period corresponding to , and the timing pulse is supplied to the recording level control circuit 14.

In the recording level control circuit 14, the pilot signal f included in the ATF pattern in the reproduced signal shown in FIG. 3(f) is delayed by the delay circuit 13.

The recording level of the rotating drum 10. of the mechanism block IO on the recording side is controlled by the recording amplifier 9 for the period of the timing pulse from the timing generating circuit 12 described above. Head A mounted on.

B and recorded on the magnetic tape 10□.

Further, FIG. 2 is a block diagram showing another embodiment according to the present invention.
5 and a switch 16 are added.

The switch 16 is switched and controlled by the above-mentioned timing pulse generated by the timing generation circuit 12, and is controlled to be in contact during the period when the timing pulse is supplied. Then, at the timing when the pilot signal is to be recorded, a signal corresponding to the biloft signal [1] generated by the signal generator 15 is supplied to the recording amplifier 9 via the recording level control circuit 14, and the rotating drum 10, Magnetic chi 110 is generated by the heads A and B mounted on the
recorded on g. Further, except when recording the pilot signal f, the switch 16 is controlled to the contact a side, and the reproduced signal delayed by the delay circuit 13 is supplied to the recording amplifier 9 and recorded on the magnetic tape 10z.

In the embodiment described above, the rotating drum II of the mechanism block 1 on the reproduction side and the rotating drum 10 of the mechanism block 100 on the recording side. Although the synchronization circuit that controls the rotation of the rotating drum 1 on the playback side has been omitted, On the other hand, the rotating drum 10 on the recording side. is configured to rotate with a deviation by the delay time in the delay circuit 13.

Furthermore, although the example was explained in which the recording level of the viroft signal f+ (130 KHz), which has the lowest frequency in the ATF pattern, is controlled, the sync signal C other than the pilot signal
The recording level of rt = 522 KHz and (s = 784 KHz) may be controlled, or the recording level of both the biloft signal and the sync signal may be controlled as necessary.

〔effect〕

According to the present invention described above, the ATF pattern is detected from the reproduced signal, and the ATF pattern in the delayed reproduced signal is detected.
Since the configuration is such that the recording level of a specific signal included in the F pattern is controlled and copied, it is possible to lower the level in advance and record a signal with poor erasing characteristics, such as a low frequency pilot signal included in the ATF pattern. In addition, since the reproduction signal is directly recorded without error correction or the like, high-speed copying can be achieved.

In addition, the configuration is such that the specific signal part in the ATF pattern described above is replaced with the correct signal generated by the signal generator, and the recording level is controlled and recorded, so even if the waveform reproducibility is poor, the correct deaity and It can be recorded as a waveform signal.

[Brief explanation of the drawing]

FIG. 1 is a block configuration diagram showing one embodiment according to the present invention, FIG. 2 is a block diagram showing another embodiment according to the present invention, and FIG. 3 is a flowchart for explaining the operation of the embodiment according to the present invention. , FIG. 4 and FIG. 5 are block configuration diagrams showing conventional examples. 1... Mechanism block on the playback side, 10... Mechanism block on the recording side, 11... ATF detection circuit,
12... Timing generation circuit, 13... Delay circuit,
14... Recording level control circuit, 15... Signal generator, 16... Switch.

Claims (2)

[Claims] (1) It has a mechanism block on the playback side that has a playback function and a mechanism block on the recording side that has a recording function, and the recorded tape is reproduced by the mechanism block on the playback side and copied by the mechanism block on the recording side. In the digital signal recording and reproducing apparatus constructed as described above, AT
an ATF detection circuit that detects an F pattern; a timing generation circuit that generates a timing pulse indicating a specific signal period in the ATF pattern based on a detection output of the ATF detection circuit; and ATF pattern detection in the ATF detection circuit. and a recording level control circuit that controls the recording level of the reproduction signal from the delay circuit only during the period when the timing pulse from the timing generation circuit is supplied. A digital signal recording and reproducing device characterized in that the recording level of a specific signal in an ATF pattern can be controlled. (2) It has a mechanism block on the playback side that has a playback function and a mechanism block on the recording side that has a recording function, and while the recorded tape is played back by the mechanism block on the playback side, it is copied by the mechanism block on the recording side. In the digital signal recording and reproducing apparatus constructed as described above, AT
an ATF detection circuit that detects an F pattern; a timing generation circuit that generates a timing pulse indicating a specific signal period in the ATF pattern based on a detection output of the ATF detection circuit; and ATF pattern detection in the ATF detection circuit. a delay circuit that delays the reproduced signal by a certain period of time necessary for the reproduction, a signal generator that generates a signal to replace a specific signal in the ATF pattern of the reproduced signal, and controls the recording level of the signal from the signal generator. and a switch that switches the recording signal supplied to the recording amplifier from the output of the delay circuit to the output of the recording level control circuit only during the period when the timing pulse from the timing generation circuit is supplied, A digital signal recording and reproducing device characterized in that a specific signal period in an ATF pattern is switched to a signal generated from a signal generator, and the recording level of the signal can be controlled.