JPH01185808A - Recording and reproducing system for rotary head type tape recorder - Google Patents

Abstract

PURPOSE:To prevent signal distortion, degrading of C/N, etc., by setting the total number of rotary heads in 2n (n is a positive integer larger than one) at the time of recording/reproducing with a rotary cylinder whose diameter is n-times of that of an ordinary cylinder and changing the rotational speed of the cylinder to 1/n-times. CONSTITUTION:At the time of recording/reproducing by using, for instance, a cylinder whose diameter is 60phi, double that 30phi of an ordinary cylinder, two rotary heads (heads A, A') for recording/reproducing with + azimuth angle are provided for the rotary cylinder 1 in positions 180 deg. distant from each other, at the same timed, other two rotary heads (heads B, B') for recording/reproducing with - azimuth angle are also provided in positions 90 deg. behind the former heads hence distant from each other by 180 deg., and the recording/reproducing is performed with the rotational sped of the cylinder, 1,000r.p.m., half that of an ordinary cylinder of 30phi-diameter. This means that the track A(B) records/reproduces on/from the first track A(B) and the head A'(B') does on from the following track A(B). As a result, the waveform of a recorded/ reproduced signal can be the same as that in the standard recording/reproducing mode.

Description

Detailed Description of the Invention (a) Industrial Application Field The present invention relates to a recording/playback method for a rotary head digital audio tape recorder (R-DAT) that uses a rotary cylinder with a diameter larger than a normal cylinder diameter (30φ). It is.

(Exposure) Conventional technology Conventionally, in such an R-DAT, each signal is recorded by dividing the area into each track on a tape that is helically scanned by a rotating head. An information recording area for recording information signals such as music converted into digital signals is formed in the center of the trace, and tracking is provided on both sides of this information recording area, that is, at the trace start and trace end of each track. A sub-code area is formed together with this area.A servo signal for tracking control is recorded in this tracking area, and a start mark indicating the beginning of the song is recorded in the sub-code area along with track number and time information. The subcode signal is recorded.

The R-DAT normally performs elegant recording and reproduction using a rotating cylinder with a cylinder diameter of 30φ at a cylinder rotation speed of 200 rpm and a tape running speed of 8.1 s.
/5ec (standard recording/playback mode), the tape is wound at a 90° angle, but recently, in order to further speed up the search, a rotating cylinder with a diameter of 60φ, twice the diameter of the normal cylinder diameter of 30φ, has been installed. The cylinder rotation speed was 20oorpm and the tape running speed was 8.15fl/5f1.
A method of winding the tape at 30° and recording and reproducing at an angle of 45° has also been considered. That is, the recording/reproduction signal waveform for a cylinder diameter of 30φ is as shown in FIG. 4, and the recording/reproduction signal waveform for a cylinder diameter of 60φ is as shown in FIG. Because the above recording pattern needs to be the same,
The signal frequency handled by a cylinder diameter of 60φ was set to twice the signal frequency handled by a cylinder diameter of 30φ.

(/1 Problem to be solved by the invention However, in the conventional recording and reproducing method, the cylinder diameter is 6.
Since the signal frequency handled during recording and playback using a 0φ rotary cylinder is twice that of the signal frequency handled during recording and playback using a normal cylinder diameter of 30φ, the high-frequency distortion of the recording signal and the rotating head and preamplifier system are used in the playback signal band. Problems with electromagnetic conversion, such as signal distortion and C/N deterioration, have arisen due to the presence of resonance points.

B) Means for Solving the Problems In order to solve the above-mentioned problems, the present invention provides a tracking control system for each track on a tape that is helically scanned by a rotating head provided on a rotating cylinder together with information signals such as music. In a rotary head tape recorder that records servo signals, etc. for the When recording and reproducing data using a rotary cylinder, the total number of rotating heads provided on the rotary cylinder is set to 2n, and the cylinder rotation speed is changed to (1/n times the normal cylinder diameter) when recording and reproducing. It's a hole.

(e) Effect: In the recording and reproducing method of the present invention described above, tape running can be stabilized and searches can be made faster by increasing the diameter of the cylinder, and the number of revolutions of the cylinder can be reduced in accordance with the diameter of the cylinder. Since the relative velocity between the tape and the head is the same as in the case of a cylinder diameter of 30φ, the electromagnetic conversion system can be made the same as in the case of a normal cylinder diameter of 30φ.

(f) Example An embodiment of the present invention will be described below with reference to the drawings.

That is, according to the recording and reproducing method of the present invention, when recording and reproducing using a rotary cylinder with a diameter of 60φ, which is twice the diameter of a normal cylinder diameter of 30φ, the rotary cylinder (1) is heated as shown in FIG. Two rotary heads (heads A, A') for recording and reproducing with an azimuth angle are installed 180 degrees apart from each other, and two rotary heads (heads E, A') for recording and reproducing with an azimuth angle of - B' heads) are placed 180 degrees apart from each other, and the cylinder rotation speed is set to 11,000 rpm, which is half that of a normal cylinder diameter of 30φ, for recording and reproduction.In other words, the rotating cylinder (1) Recording and reproduction are performed by first recording and reproducing the first A track with the A head, the first B track with the B head, the next A track with the A' head, and the next B track with the B' head. The recording/reproducing signal waveform is the same as in the standard recording/reproducing mode using a normal cylinder diameter of 30φ provided with two recording/reproducing rotary heads as shown in FIG. 4 (aJ).

Specifically, tape recording using a rotary cylinder having a cylinder diameter of 60φ will be explained using the system configuration example shown in FIG. That is, when the key scan unit (2) specifies recording according to the method of the present invention, the control circuit (3) controls the digital signal processing circuit (4), the recording/reproducing amplifier (5), the cylinder servo circuit (6), and the capstan servo circuit. (7),
Control the reel servo circuit (8).

That is, the digital signal processing circuit (4) is controlled by the control circuit (3) through the control line (9) to set the sampling frequency to 48 KHz using the A/D converter αO.
The digitally converted information signal is subjected to addition of an error correction code, interleaving, etc., and outputted at a predetermined timing, and this information signal is first amplified by a recording/reproducing amplifier (5) and then passed through a rotating cylinder (company). Recorded in the information recording area. Here, it is assumed that the signal frequency handled by the digital signal processing circuit (4) has been changed to be the same as the signal frequency handled by a normal cylinder diameter of 30φ. and,
The recording/playback amplifier (5) is also a control circuit using a control line.
(1-\Calyx 1 It is assumed that the recording mode has been switched by the control from (3). Also, the cylinder servo circuit (6), capstan servo circuit (7), and reel servo circuit (8) are each Control line 03Q4) Control from the hunt roll circuit (3) by αS allows the system to operate at a tape running speed of 5.15fl/8θ0, which is the same as the normal cylinder diameter of 30φ, and the number of rotations per cylinder is 1100Orp, which is 1/2 times as much. Motor αe1 Capstan motor αD1 Controls the rotation of the reel motor αIHI.

In addition, when playback is specified in the key scan unit (2), the information signal from the recording area of the information reproduced from each head passes through the rotary cylinder I, is amplified by the recording/reproducing amplifier (5), and is then amplified by the equalizer ■ to form a waveform etc. After being digitized, the information signal is sent to a digital signal processing circuit (4), and the information signal is error-corrected and de-interleaved in this digital signal processing circuit (4), and then sent to a D/A conversion circuit (Inc.). , will be output as the original analog information signal.

In addition, FIG. 3 (jl shows the recording/reproduction signal waveform in the case of n-2 of the present invention, and FIG. 3(a) shows a cylinder diameter of 30φ and a
The cylinder rotation synchronization signal waveform in the case of 0 Orpm, the same figure (equalized recording and reproduction signal waveform of the A head, the same figure U is the recording and reproduction signal waveform of the B head, the same figure (dJ is the combined recording and reproduction signal of these) Waveform, figure 0] is cylinder diameter 6
Cylinder rotation synchronization signal waveform in case of iooorpm at 0φ, same figure (mouth IglQ1) [11 is its A, B%h'
, B' head recording/reproducing signal waveform.

(G) Effects of the Invention As mentioned above, in the recording and reproducing method of the present invention, by increasing the diameter of the cylinder, it is possible to stabilize the tape running and increase the speed of the search. The relative velocity between the tape and the head is the same as when the cylinder diameter is 30φ, so the electromagnetic conversion system is made smaller than the normal cylinder diameter of 30φ.
It can be done the same as in the case of

[Brief explanation of the drawing]

FIG. 1 is a diagram showing a rotating cylinder with a cylinder diameter of 60φ and its signal waveform as an embodiment of the present invention, FIG. 2 is a system configuration diagram of R-DAT used in the present invention, and FIG. 3 is a diagram of its signal waveform. FIG. 4 is a diagram showing conventional rotating cylinders with different cylinder diameters and their signal waveforms. (1)... Rotating cylinder, (3)... Control circuit, (6)... Cylinder servo circuit, (7)...
... Capstan servo circuit, (8) ... Reel servo circuit.

Claims (1)

[Claims] (1) A rotating head type tape in which information signals such as music and servo signals for tracking control are recorded in area-divided areas on each track of the tape, which is helically scanned by a rotating head installed on a rotating cylinder. In a recorder, the normal cylinder diameter (30φ) is n times (
However, when recording and reproducing using a rotating cylinder with a diameter of (n is a positive integer greater than 1), the total number of rotating heads provided on the rotating cylinder is set to 2n, and the number of rotations of the cylinder is set to 2n. 1/n when using diameter
A recording and reproducing method for a rotary head type tape recorder characterized by recording and reproducing by changing the number of times.