JPH0341908B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a magnetic recording and reproducing device having an automatic song selection function for locating the beginning of a recorded portion of an audio signal recorded on a magnetic recording medium such as a magnetic tape, and in particular, The present invention relates to a magnetic recording and reproducing apparatus which allows a recording and reproducing head to perform an audio signal recording and reproducing operation and a detecting operation for locating the beginning of a recorded portion.

Conventionally, as an automatic song selection function in a magnetic recording/reproducing device such as a tape recorder, a first method is used to sequentially detect unrecorded portions existing between recorded portions of an audio signal formed on a magnetic recording medium on which an audio signal is recorded. and a second method in which a control signal indicating the absolute address of the recorded portion is recorded in an unrecorded portion upstream of the recorded portion and detected by the control signal that is played back. It has been known.

By the way, if the above-mentioned detection of unrecorded parts or control signals and the recording and reproduction of audio signals are performed by one recording/playback head, an automatic song selection function (so-called AMS function) based on the unrecorded part detection method can be used. It is not possible to locate the beginning of the audio signal on a magnetic recording medium in which control signals are recorded in the unrecorded portions, and devices equipped with an automatic music selection function (so-called RMS function) using a control signal detection method cannot In this case, it is not possible to cue the beginning of an audio signal on a magnetic recording medium on which no control signal is recorded. That is, conventionally, recorded magnetic recording media could not be used interchangeably between the above-mentioned methods.

SUMMARY OF THE INVENTION Therefore, the present invention provides a magnetic recording and reproducing device with a novel configuration that allows recording and reproducing audio signals and control signals using a single recording and reproducing head, and also detects unrecorded portions. Automatic song selection can be performed using either the section detection method or the control signal detection method, and the control signal representing the absolute address recorded in the unrecorded section of the magnetic recording medium by the device of the present invention is an audio signal. If the magnetic recording medium is installed in a device equipped only with an unrecorded section detection method and an automatic song selection operation is performed, the section on which the control signal is recorded is The object of the present invention is to enable it to function as a non-recording section, and to enable it to be used with compatibility with devices equipped only with a non-recording section detection method, which has not been possible in the past.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to drawings showing an embodiment in which the present invention is applied to a stereo tape recorder.

In the magnetic recording and reproducing apparatus according to the present invention, stereo audio signals are recorded, for example, on two parallel recording channels 2 and 3 along the longitudinal direction of a magnetic tape 1, as shown in FIG. Note that the track pattern on the magnetic tape 1 may conform to a desired standard; for example, the track width W of each recording track 2 and 3 is 0.6 mm, and the distance h between the track centers of the two channels is 0.9 mm. shall be.
The left channel side component of the stereo audio signal is recorded on the first recording track 2, and the right channel side component is recorded on the second recording track 3. Further, after recording audio signals on each of the recording tracks 2 and 3 of the magnetic tape ₁ , as shown in FIG.
A control signal indicating the absolute address of _A2 is recorded by the recording/reproducing head 10 in unrecorded sections _Z1 and _Z2 on the upstream side of each of the above-mentioned recorded sections _A1 and _A2 .

For example, as shown in FIG. 3, the recording/reproducing head 10 for recording and reproducing stereo audio signals and control signals on each of the recording tracks 2 and 3 of the magnetic tape 1 has a length equal to the track width W. The magnetic gap 12 and 13 are arranged side by side with the above-mentioned center-to-center distance h. This recording/reproducing head 10 connects each recording track 2 and 3 of the magnetic tape 1 to each magnetic gap 1.
2 and 13 are in contact with each other independently, and the azimuth angles of the magnetic gaps 12 and 13 are set to be equal. Further, the recording/reproducing head 10 includes:
For example, by guiding the head base 11 by the slide cam plate 15, the arrangement angle with respect to the magnetic tape 1 is changed, and in this embodiment, the first angular position where the azimuth angle of each magnetic gap 12, 13 is 0°. and a second angular position where the azimuth angle is α°.

Recording and reproduction of the stereo signal is performed with the recording and reproduction head 10 set at the first angular position. Further, the recording and reproducing of the control signal is performed with the recording and reproducing head 10 set at the second angular position.

By changing the angular position of the recording/reproducing head 10, the angle formed by the magnetic gaps 12 and 13 at the first angular position and the second angular position, that is, the azimuth angle α in this embodiment is changed. and the recording wavelength λ of the control signal recorded at the azimuth angle α means that when the control signal recorded at the azimuth angle α at the second angular position is reproduced at the first angular position, In addition, conditions are set such that the azimuth loss P is maximum and the phases of the reproduction control signals are opposite between the channels. The above azimuth loss P is: P=20log ₁₀ |smi(πWtanα/λ)/πWtanα/λ|…
...Since it is expressed by the first equation (1st equation), λ=W·tanα/m ...The maximum value is obtained when the second equation (2nd equation) is satisfied. In addition, in order to make the playback control signals have opposite phases between each channel, as is clear from Fig. 4, htanα=2n-1/2・λ...the third equation must be satisfied. Therefore, it is necessary to set the above-mentioned angle α and wavelength λ so as to satisfy the following equation: λ=2h·tan α/2n−1 . Therefore, in this embodiment, as mentioned above, the track width W is set to W = 0.6 mm, and the distance between track centers h is set to h = 0.9 mm, so that the above-mentioned equations 2 and 4 can be satisfied at the same time. The coefficients in each equation are matched, and 0.6/m=1.8/2n-1 ...the fifth equation is transformed into the fifth equation.n=3/2m+1/2...the sixth equation is satisfied. Integer solutions An of n and m are obtained: m=n=2 m=1, n=5 m=3, n=8 m=5. Therefore, in this embodiment, λ=0.6tanα... By satisfying the seventh equation, the azimuth loss P
is maximum, and the phase of the reproduction control signal can be reversed between each channel. Therefore, in this embodiment, for example, n=2 and m=1, and the recording wavelength λ
is the control signal of λ=0.1 (f=1000Hz), α=
The angular position of the recording/reproducing head 10 may be freely switchable so that recording is performed at a serious angle α of 4°36'.

Therefore, in the apparatus of this embodiment equipped with the recording/reproducing head 10 as described above, the recording/reproducing head 10 sends a desired audio signal to each recording track 2, 3 on the magnetic tape 1 at the first angular position. After recording, the following automatic song selection operation can be performed by recording control signals of the same phase for each channel at the second angular position using the recording/reproducing head 10.

That is, by setting the recording/reproducing head 10 to the second angular position and performing reproduction, the control signal can be reproduced, so that the so-called RMS operation using the control signal, that is, the reproduction of an arbitrary location based on the information of the absolute address, can be performed. It is possible to cue the audio signal.

Furthermore, if reproduction is performed with the recording/reproducing head 10 at the first angular position, the control signal is attenuated by azimuth loss and is reproduced in an opposite phase state between each channel, so that the sum thereof becomes zero. Therefore, the unrecorded portions Z ₁ and Z ₂ can be detected by determining the signal level of the sum of the reproduction outputs of each channel from the recording and reproduction head 10. Therefore, by counting the number of times the unrecorded portions Z ₁ , Z ₂ , . . . are detected, the so-called AMS operation, that is, cueing of the audio signal based on the relative address information can be performed. Moreover, when the recording/reproducing head 10 is disposed at the first angular position and the audio signal is reproduced, the sum of the reproduction outputs of the control signals becomes zero as described above, so that the noise caused by the control signals is reduced. Occurrence can also be sufficiently suppressed.

Furthermore, since the device of the above-described embodiment has the RMS function and the AMS function as described above, it is possible to use the magnetic tape with a general magnetic recording/reproducing device that only has one of the song selection functions. compatibility can be obtained.

As is clear from the description of the embodiments described above, according to the present invention, each magnetic gap is formed independently at the same azimuth angle in at least two channels of recording tracks formed along the longitudinal direction of a magnetic recording medium. The head is provided with a recording/reproducing head which is brought into contact with the receiver, and has an azimuth angle between a first angular position for recording and reproducing an audio signal and a second angular position for recording and reproducing a control signal indicating an absolute address of the recorded audio signal. In the magnetic recording and reproducing apparatus, the arrangement angle of the recording and reproducing head is changed so that the angles are different, and the recording and reproducing head records and reproduces an audio signal and a control signal. The relationship between the angle α formed by the magnetic gap between and the second angular position and the recording wavelength λ of the control signal is expressed as (integer) and λ=2h・tanα/2n−1 (where h is the distance between the centers of recording tracks of two channels, and n is a positive integer). The control signal is recorded in the unrecorded portion formed between the recorded portions on which the audio signal is recorded, and
By zeroing out the sum of the playback outputs from the two channels of recording tracks obtained when the unrecorded portion is traced by the recording and playback head located at the position, the audio signal and By making it possible to record and reproduce control signals and detect unrecorded portions, a single recording and reproduction head can perform both the RMS function and the AMS function. Moreover, when reproducing the audio signal, the control signal recorded in the non-recording section can be sufficiently suppressed. Furthermore, it is also possible to provide a magnetic tape that is compatible with magnetic recording devices that have only either the RMS function or the AMS function.

[Brief explanation of drawings]

1 to 4 show an embodiment of the present invention, FIG. 1 is a schematic diagram of a recording track formed on a magnetic tape in this embodiment, and FIG. 2 also shows a recording format on the recording track. Pattern diagram,
FIG. 3 is a schematic front view of a recording/reproducing head portion used for recording/reproducing in the recording format, and FIG. 4 is an explanatory diagram for explaining the principle of recording/reproducing control signals. 1... Magnetic tape, 2, 3... Recording track,
10... Recording/reproducing head, 12, 13... Magnetic gap, 15... Slide cam plate for changing the arrangement angle of the recording/reproducing head, W... Recording track width, h
... Distance between track centers, α ... Angle of change of magnetic gap.

Claims (1)

[Scope of Claims] 1. A recording/reproducing head in which each magnetic gap independently contacts at least two channels of recording tracks formed along the longitudinal direction of a magnetic recording medium at equal azimuth angles; The recording and reproducing head is arranged at an angle such that the azimuth angle is different between the first angular position where the signal is recorded and reproduced and the second angular position where the control signal indicating the absolute address of the recorded audio signal is recorded and reproduced. In a magnetic recording and reproducing apparatus in which the recording and reproducing head records and reproduces audio signals and control signals, the angle α formed by the magnetic gap between the first angular position and the second angular position is The relationship between λ and the recording wavelength λ of the control signal is expressed by the following formula: λ=W・tanα/m (where W is the width of the recording track and m is a positive integer), and λ=2h・tanα/2n−1 (where, h is the distance between the centers of the recording tracks of two channels, and n is a positive integer). The above control signal is recorded in the recording part, and the above first control signal is recorded.
By reducing the sum of the playback outputs from the recording tracks of the two channels obtained when the unrecorded portion is traced by the recording and playback head located at the position of and a magnetic recording and reproducing device that is capable of recording and reproducing control signals and detecting unrecorded portions.