JPH033101A - Tape recorder - Google Patents

Abstract

PURPOSE:To execute recording and reproducing extending to threefold time as compared with time when a tape recorder is used as a VTR by dividing the magnetic layer of a tape into three layers of a surface layer, an intermediate layer and a deep layer and executing the recording and reproducing when the tape recorder is used only for an audio. CONSTITUTION:Three sets of magnetic heads mutually having different azimuth angles are fitted to a rotating cylinder at prescribed intervals. Then, when the tape recorder is used only for the audio, an audio signal is recorded on the deep layer 43 of the tape 4 by the first head with the aid of setting the carrier frequency thereof as 2MHz and the recording current thereof as I3, for example, at the first recording time. Next, at the second recording time, it is recorded on the intermediate layer 42 of the tape 4 by setting the carrier frequency as 4MHz and the recording current as I2(I2<I3). Besides, since it is recorded on the surface layer 41 by the third head with the aid of setting the frequency as 6MHz and the current as I1(I1<I2) at the third recording time, the recording and reproducing extending to threefold time as compared with the time when the tape recorder is used as the VTR is executed.

Description

[Detailed description of the invention] [Industrial application field] This invention relates to tape recorders.

[Summary of the invention]

This invention enables a tape recorder that can be used as a VTR or an audio-only device to record and play back high-quality sound over a long period of time by performing deep recording when operated as an audio-only device. .

[Conventional technology]

In 8 mm video, as an optional standard, it is permitted to convert an audio signal to a PCM signal, compress the time axis, and record and reproduce this PCM audio signal in an overscan section of a video track. It is also permitted to record and reproduce the PCM audio signal on a video track for a long time.

Document: Specification and drawings of Japanese Patent Application No. 57-15287 [Problem to be Solved by the Invention] However, in Beta system and VH3 system VTRs, an overscan system that only records and reproduces a PCM audio signal on a video track is used. Since there is no section, it is not possible to record and reproduce PCM audio signals using methods such as 8 mm video, or to perform long recording and reproduction using video tracks.

This invention attempts to solve these problems.

[Means to solve the problem]

Therefore, in the present invention, in the first recording mode, the first information signal is recorded on the deep side of the magnetic layer of the magnetic tape, and the second information signal is recorded on the deep side of the magnetic layer of the magnetic tape. Recorded on the surface side of the magnetic layer, the second
In the recording mode, the second information signal is recorded on the deep layer side of the magnetic tape for the first time,
In the tape recorder, the second information signal is recorded on the surface layer side of the magnetic tape at the second time.

[Effect]

One tape recorder can be used as a VTR or as a PC.
It operates as a tape recorder that can record and reproduce M audio signals over a long period of time.

〔Example〕

Figure 1 shows a recording system. When recording as a VTR, for example, a color composite video signal of the NTSC system is
The signal is supplied to a Y/C separation circuit (12) through a terminal (11) and separated into a luminance signal sy and a carrier color signal Sc.
The signal sy is supplied to the FM modulation circuit (13), and as shown in FIG.
．． 4MHz, 7. at white peak. It is converted into an FM signal Sf of OMHz, and this FM luminance signal Sf is supplied to an adder circuit (14).

Further, the signal Sc from the separation circuit (12) is supplied to the frequency converter (15), and as shown in FIG. 3A, the carrier frequency fc is fc=40 fh (fh is the horizontal frequency. fcζ629kHz), and The frequency is converted into a carrier color signal Sc whose phase is changed by 90° every horizontal period, and this signal Sc is supplied to an adder circuit (14).

Therefore, from the adder circuit (14), the signals S[ and Sc
A summation signal Ss is extracted from the summation signal Ss.
s is supplied to the rotating magnetic heads (IA) and (1B) through a signal line from the recording amplifier (16> to the switch circuit (17) to the switch circuit (18)).

In this case, the switch circuit (17) is always turned on by the system controller (9) during recording as a VTR. Further, the switch circuit (18) is switched every one field period in synchronization with the rotation of the heads (IA) and (1B).

Further, the heads (1 person) and (1B) have different azimuth angles, for example, +6° and -6°, and are spaced apart from each other by 180°, for example, as shown in FIG. It is rotated at the frame frequency in synchronization with sy. And this head (IA), (
1B) The magnetic tape (4) is 18
It runs diagonally over an angular range of just over 0 degrees, and
The vehicle is driven at a predetermined speed.

Therefore, on the tape (4), the signal Ss is spread over j so that its ■ field forms one diagonal magnetic track.
It is recorded from time to time.

Further, for example, stereo left and right channel audio signals are supplied to the A/D converter (22) through terminals (21L) and (21R), and are linearly quantized into 16 bits per sample at a sampling frequency of 48kHz, for example. This PCM audio signal Sp is converted into a serial PCM signal Sp, and this PCM audio signal Sp is supplied to an encoder (23) and subjected to encoding processing for error correction and a slight time axis compression to become a signal Se. In addition, the pit of the signal Se at this time is
The output is 48kHz x 15 bits x 2 channels + redundant bits 2MbpS.

This encoded signal Se is then supplied to the 0-QDPSK modulation circuit (24) as modulation power, and
A carrier signal is supplied from the carrier forming circuit (25) to the modulation circuit (24), and the signal Se is converted into a 0-QDPSK signal So. However, in this case, the system controller (9
) controls the switch circuit (251) to connect the crystal oscillator X3 to the formation circuit (25), and as shown in FIG.
As shown in , the carrier frequency of the signal SO is 2! A H
z, the band is 1° where the carrier frequency is ±1 MHz.Then, this signal SO passes through the recording amplifier (26) and further through the switch circuit (28) to the rotating magnetic head (2).
A) and (2B) are alternately supplied every one field period.

In this case, the switch circuit (261
) is controlled, resistor R2 is connected to the amplifier (26), and from the amplifier (26) the head (2A), (2B)
The recording current of the signal So supplied to is set to a predetermined magnitude.

Furthermore, the heads (2A) and (2B) have an angular spacing of 180° from each other, as shown in FIG.
It is rotated together with the heads (IA) and (1B). Also, at this time, heads (2A), (2B)
are adjacent to and preceding the heads (IA>, (1B), respectively, and the heads (2A), (2B)
If the scanning trajectories of the heads (LA) and (1B) match each other, the azimuth angle of the heads (2^) and (2B) will be (I
A), (1B> are different magnitudes in the same direction, for example +20°, -20°.Furthermore, the head liability IA
) or (18) so that the signal So is supplied to the head (2A) or the head (2B) during the field period when the signal Ss is supplied to the switch circuit (18);
(28) The phases of the switching are matched.

Also, for example, the stereo left and right channel audio signals are supplied to the FM modulation circuit (32L), (32R) through the terminals (31L), (31R), and the carrier frequency is adjusted as shown in FIG. 3A. 1.
3MHz and 1,7M)Iz FM signals Sl and Sr, these FM audio signals Sl and Sr are supplied to an adder circuit (33) to produce a sum signal Sa of the signals Sl and Sr, and this signal Sa is Recording amplifier (36)
→ Switch circuit (37) → Rotating magnetic head (3A>, (3B) through the signal line of switch circuit (38)
supplied to

In this case, the switch circuit (37) is turned on by the system controller (9) during recording as a VTR. Further, the switch circuit (38) is connected to the head (3^), (3
It is switched every one field period in synchronization with the rotation of step B).

Further, as shown in Fig. 4, the heads (3A) and (3B> have an angular interval of 180° from each other, and are rotated together with the heads (1 person) and (1B). At this time, head (3A), (313)
are adjacent to and preceding heads (2A> and (2B>), respectively, and heads (3A) and (3B)
The azimuth angles of the heads (38) and (3B) are arranged so that the scanning trajectories of the heads (IA) and (1B) coincide with the scanning trajectories of the heads (IA) and (1B).
A), (1B) in the opposite direction, e.g. -30°, +3
It is assumed to be 0°. Furthermore, the head (18) or IB)
The switching phases of the switch circuits (18) and (38) are adjusted so that the signal 3a is supplied to the head 3A or the head (3B) during the field period when the signal Ss is supplied to the head.

Therefore, when recording on a VTR, one field of the signal Sa is first recorded as one diagonal magnetic track by the head controller 3A) or (3B), and then the magnetic track of the signal Sa is overlapped with the head controller (3A) or (3B). 2A) or 2B) causes 1 field of signal So to be diagonal 1
The signal Sa,
One field of the signal Ss is recorded as one diagonal magnetic track by the head (3A) or (3B) overlapping the magnetic trunk of the signal S.
By setting the magnitudes of the recording currents a, So, and Ss, as shown in FIG.
a is recorded, the PCM audio signal SO is mainly recorded on the intermediate layer (42), and the video signal Ss is mainly recorded on the surface layer (41).

Fig. 2 shows the playback system. During playback as a VTR, the heads (IA) and (IB) control the surface layer (41) of the tape (4) whose azimuth angle matches that of ) is alternately reproduced every field period, and this signal Ss is supplied to the switch circuit (51) to form a continuous signal Ss.Then, this signal Ss is transmitted to the reproduction amplifier (52). The FM luminance signal S is supplied to the band pass filter (53) through the filter (53), and the FM luminance signal S[
) is supplied to the FM demodulation circuit (55), where the luminance signal sy is demodulated, and this signal sy is supplied to the addition circuit (56).

Further, the signal Ss from the amplifier (52) is supplied to a bandpass filter (63) to extract the carrier color signal Sc, and this signal Sc is supplied to the frequency converter (65) through the ACC circuit (64). is frequency-converted to a carrier color signal Sc having a carrier frequency of 1, and is subjected to phase processing and complementary phase processing during recording to produce a signal Sc having the original phase, and this signal Sc is passed through a C-shaped comb filter ( 66) to the adder circuit (56).

Therefore, the original color composite video signal is obtained from the adder circuit (56) and taken out to the terminal (57).

In addition, the heads (2A) and (2B> cause the PCM audio signal SO to be transmitted every one field period from the intermediate layer (42) of the tape (4) whose azimuth angle matches that of the heads (2A) and (2B). This signal SO is alternately reproduced and is supplied to a switch circuit (71) to produce a continuous signal S.

It is said that This signal So is transmitted to the reproducing amplifier (72
) and a bandpass filter (73).
The encoded signal Se is supplied to the SK demodulation circuit (74).
is demodulated, this signal Se is supplied to the decoder (75) to decode the PCM signal Sp, error correction and error correction are performed, and this signal Sp is sent to the D/A
It is supplied to a converter (76) and converted into the original audio signal, which is taken out to terminals (77L) and (77R).

Furthermore, due to the head responsibility (3A), (3B>), the FM audio signal Sa is alternately transmitted every one field period from the deep layer (43) of the tape (4) whose azimuth angle matches that of the head (3A), (3B). This signal Sa is supplied to a switch circuit (81) to form a continuous signal Sa.Then, this signal Sa is passed through a reproduction amplifier (82) to a bandpass filter (83L).
, (83R) and take out the signals SI, Sr, and these signals SI, Sr are supplied to the limiter <84L
), (84R) through the FM demodulation circuit (85L)
, (85R) and demodulates the original audio signal, which is then sent to terminals (87L) and (87R).
It is taken out.

On the other hand, in Fig. 1, when recording as an audio tape recorder, the switch circuit (
17) and (37) are turned off, and only the PCM audio signal SO is recorded on the tape (4).

However, in this case, at the time of the first recording, the system controller (
9), switch circuits (251), (261>
is controlled, and the crystal oscillator X3 and resistor R3 are connected to the formation circuit (25) and the amplifier (26), and as a result,
The carrier frequency of the signal So is set to 2 MHz, for example, as shown in No. 3-8, and the recording current of the signal So is set to a predetermined and relatively large value Is.

Therefore, the signal SO is applied to all layers (
41) to (43>).

In this way, the first audio signal recording is performed over, for example, the entire length of the tape (4).

Next, when recording the audio signal for the second time, the oscillation element , for example, 4 MHz, and the recording current of the signal SO has a predetermined magnitude (12N2<IO).
It is said that

Furthermore, at this time, although not shown, tracking servo similar to that during playback is performed on the track of the signal SO formed by the first recording, and the rotational phase of the heads 2A) and (2B) is performed. is shifted by 180 degrees, and the head (2A) or (2B) is
The head (
2B) or (28), the signal SO is overwritten.

However, at this time, the magnitude of the recording current of the signal SO is I
Since 2<1*, the signal So is not recorded in the deep layer (43) of the tape (4), but in the surface layer (41) and the intermediate layer (
42).

Furthermore, when recording the third audio signal, the oscillation element X1 and the resistor R+ are connected to the forming circuit (25) and the amplifier (26), and the carrier frequency of the signal SO is as shown in Figure 3. For example f3! , I Hz, and the recording current of the signal SO has a predetermined magnitude I
l (I l < 12).

Also, at this time, similar tracking servo is performed on the track of the signal SO formed by the first recording during reproduction, and the heads (2A>, (2B)
The rotational phase of is made equal to that during the first recording.

Therefore, the signal SO at the time of the third recording is overwritten on the trunk by the first and second recording, but at this time, since I+<I2, the signal SO is in the middle of the tape (4). It is not recorded in the layer (42) or the deep layer (43), but is recorded only in the surface layer (41).

Therefore, when the above three recordings are performed, as shown in Figure 5, the first signal So is recorded in the deep layer (43) of the tape (4), and the signal So in the middle layer (42) is There is a second
The signal SO of the third time is recorded, and the signal SO of the third time is recorded on the surface layer (41).

Also, at this time, the deep layer (43) and the intermediate layer (42),
The occupied bands of the signal SO are different between the surface layer (41) and the surface layer (41).

Furthermore, at this time, due to the tracking servo, as shown in FIG.
The azimuth angle changes from +20° to -20° for each track (4T), and in the middle layer (42), contrary to the deep layer (43), the azimuth angle changes by +20° for each track (4T). °
In the surface layer (41), the azimuth angle changes from +20° to -20° for each track (4T), contrary to the intermediate layer (42).

During playback as an audio tape recorder, the passband of the bandpass filter (73) is controlled by the system controller (9), and the signal S recorded in the deep layer (43) is controlled by the system controller (9).
When reproducing O, the passband has a center frequency of 2 M It z, as shown in Section 3-8, and an intermediate layer (
When reproducing the signal SO recorded on the surface layer (42), the pass band has a center frequency of 4 MHz, and when reproducing the signal So recorded on the surface layer (41), the pass band has a center frequency of 6 MHz. Frequency. Also, the head (2A)
, (2B) are also the rotational phases of each layer (43) to (41
) is controlled to match the azimuth angle of

Therefore, by switching the passband of the filter (73), the deep layer (41) and the intermediate layer (4) of the tape (4) can be changed.
2) Alternatively, the signal SO recorded on the surface layer (41) is selected and the audio signal is reproduced.

Thus, according to the present invention, the tape can be used as a VTR or as an audio tape recorder, and in this case, especially according to the present invention, when operating as an audio tape recorder, the tape (
) is divided into three layers: the front layer (41), the intermediate layer (42), and the deep layer (43) for recording and reproduction, so recording or reproduction can be performed for three times as long as when used as a VTR. Can be played.

Furthermore, since the audio signal is recorded and reproduced in the form of a PCM signal, recording and reproduction can be performed with high sound quality.

In the above description, when recording and playing back as an audio tape recorder, recording and playback to the deep layer (43), middle layer (42), and surface layer (41) are all performed by the head (2).
A) and (2B), but the heads (3A, 3B), (2^, 2B), (IA,
1B) can also be performed.

In addition, in the above description, the magnetic layer of the tape (4) is composed of three layers (
41) to (43) were divided into two layers for recording and playback, and the upper layer (surface side) and lower layer were divided into two layers, and the video signal Ss and the FM audio signal Sa or the PCM audio signal twice were placed on the upper layer (surface side) and the lower layer. It is also possible to record and reproduce So.

Furthermore, when performing the second recording/reproduction on the intermediate layer (42) as an audio tape recorder, the tape (4) may be run in the opposite direction. Alternatively, a QPSK signal such as a 0-QPSK signal may be used as a 0-QDPSK signal So signal S light.

〔Effect of the invention〕

According to this invention, the tape can be used both as a VTR and as an audio tape recorder. In this case, especially according to the invention, when operating as an audio tape recorder, the magnetic layer of the tape (4) is Since recording and reproduction is performed by dividing the device into three layers: the surface layer (41), the middle layer (42), and the deep layer (43), recording or reproduction can be performed for three times as long as when used as a VTR.

Furthermore, since the audio signal is recorded and reproduced in the form of a PCM signal, recording and reproduction can be performed with high sound quality.

[Brief explanation of drawings]

FIGS. 1 and 2 are system diagrams of an example of this invention, and FIGS.
FIG. 5 is a diagram for explaining this. (IA) ~ <3rd) are rotating magnetic heads, (4) are magnetic tapes, (11> ~ (38) are recording systems, (51> ~ (87)
R) is a regeneration system. Agent Hidemori Matsukuma Figure 3 Figure 4 Figures 1A to 3B; Head Figure 4

Claims (1)

[Claims] In the first recording mode, a first information signal is recorded on the deep side of the magnetic layer of the magnetic tape, and a second information signal is recorded on the magnetic layer of the magnetic tape. In the second recording mode, the second information signal is recorded on the deep side of the magnetic tape in the first recording mode, and in the second recording mode, the second information signal is recorded in the deep layer side of the magnetic tape. A tape recorder in which information signals No. 2 are recorded on the surface layer side of the magnetic tape.