JPH063666B2 - Recording track control device - Google Patents

Description

TECHNICAL FIELD OF THE INVENTION The present invention relates to a recording track control device for recording an audio signal on an unrecorded track in a PCM multi-track system using an 8 mm video tape.

[Prior Art and its Problems] As a VTR, a 1 / 2-inch VTR has been generally popular, but an 8 mm VTR has recently been put into practical use. In this 8mm VTR, P as an option
Recording / playback of a CM audio signal is possible.

Then, recently, a PCM multi-track system has been considered in which the PCM audio signal can be recorded for a long time by using the 8 mm VTR tape. In this PCM multi-track system, an 8 mm video is a PCM audio recording area as it is, and the video signal recording area is divided into 5 tracks.
An MM audio signal of 540 minutes (9 hours) can be recorded on an 8 mm video cassette for 0 minutes. If the 8 mm video PCM multi-track method is used as described above, long-time recording is possible.
Since it is recorded on 6 tracks, it is very difficult to grasp the recording status of each track. For this reason, for example, when urgently recording an FM broadcast program or the like, first to sixth
Sometimes, you may accidentally erase an important recording without knowing which of the tracks has already been recorded.

Further, in the 8 mm video PCM multi-track system, different signals are recorded / reproduced by using the same tape as the 8 mm VTR, so that it is necessary to identify both. To date, M. T. S (Mu
lti-Track mode recognition
n Signal) is recorded at the same time as the PCM multi signal, and at the time of reproduction, it is proposed to judge whether the signal is the PCM multi signal or not by the presence or absence of this signal. This is 2 when recording PCM data on tape.
A 28.78 KHz signal is recorded by frequency multiplexing. As described above, in the PCM match truck system, the M.M. T. It is necessary to record S on the tape,
Conventionally, M. T. S is only used to determine whether the tape is a PCM multi tape.

[Object of the Invention] The present invention has been made in view of the above points, and even in the case of urgent recording, there is no fear of accidentally erasing the recorded contents, and it is possible to reliably record on an empty track. An object is to provide a recording track control device.

[Points of the Invention] The present invention relates to a case where a specific key is operated when recording a PCM audio signal. T. S is used to detect an unrecorded track in the tape, and when there is an unrecorded track, an arbitrary track in the track is automatically selected and signal recording is performed.

[Embodiment of the Invention] An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows a case where the present invention is applied to a magnetic recording / reproducing apparatus having a recording / reproducing function of an 8 mm VTR and a PCM multi-track system. In FIG.
10 is a key input part, 8mm VTR mode or PCM
Mode switch 1 that presents multiple modes as options
PCM track designation key 2 for designating the sixth PCM track, QREC (QUICK) operated during emergency recording, etc.
RECORD) key 33, PLAY for instructing playback operation
Various operation keys such as a key 4 and a REC key 5 for instructing a normal recording operation are provided. The operation signal of each key in the key input unit 10 is sent to the system controller 11. The system controller (11) outputs a display signal to the display drive circuit 12 in response to a key operation or the like, and outputs a signal corresponding to the track designated by the PCM track designation key 2 to the PCM control signal generation circuit 13. . Further, the system controller 11 causes the mode designating signals V / P and PLAY for switching the mode according to the operation of the mode switch 1.
The recording / reproducing signal R / P for switching and specifying recording and reproducing according to the operation of the key 4 or the REC key 5 and the check signal QR which is at a high level for a certain time by the operation of the QREC key 3 are output. Then, the display drive circuit 12
Is displayed according to the signal from the system controller 11.
Display drive 14 On the display part (14), the first to sixth track display parts 15 formed by being inclined so as to correspond to the PCM tracks on the tape are printed on the center part, and both sides of each display track are printed. Further, a recorded track display body 16 and a reproducing track display body 17 are provided. Also,
As shown in FIG. 2, the PCM control signal generation circuit 13 delays the head switching signal HSW sent from a servo system circuit (not shown) according to a designated track, and selects track selection signals PSW1 to PSW6, A, A track pulse PT synchronized with each read track by the rotary heads HA and HB of the B channel, and a check timing signal CSW that is at a high level while the recording of the first to sixth tracks is read by the rotary head HA are output. In this case, the track selection signal PSW1 is output in the same phase as the head switching signal HSW, and PSW2 to PSW6 are output sequentially delayed by 36 °. The head switching signal HSW has a high level and a low level of 180 °, respectively,
It has a time width of 16.6 msec corresponding to one field.

Although not shown, the rotary heads HA and HB are mounted on a rotary drum at an interval of 180 °, and the rotary drum has a constant speed in synchronization with the head switching signal HSW by a servo circuit. It is driven to rotate.
Then, 2 mm of 8 mm video tape is attached to the rotary drum.
It is wound diagonally in the angle range of 21 ° and driven to run at a constant speed. Therefore, as shown in FIG. 3, the 8 mm video tape 18 has two tracks 19 inclined at a constant angle.
The rotary heads HA and HB are alternately formed in parallel and sequentially. In the PCM multi-track system, the recording track 19 is a first to sixth track Tr that is offset by 36 °.
1 to Tr6. The first track Tr1 is
The PCM audio track normally provided on the 8 mm video tape, the second to sixth tracks Tr2 to Tr6 is 18
It is a track formed in the 0 ° video area.

Further, in FIG. 1, 21 is a recording video signal input terminal, 2
Reference numeral 2 is a recording audio signal input terminal. The video signal externally input to the terminal 21 is sent to the video signal recording circuit 23,
The recording audio signal externally input to 22 is sent to the PCM recording circuit 24. The output signal of the video signal recording circuit 23 is amplified by the amplifier 25 and then input to the common terminal of the changeover switch 27 via the changeover switch 26. The changeover switch 26 switches between the VTR terminal and the PCM terminal according to the control signal V / P output from the system controller 11, and the VTR terminal is connected to the common terminal of the changeover switch 27. The common terminal of the changeover switch 27 is connected to the terminal H or the terminal L by the head changeover signal HSW. Then, the PCM recording circuit 24 is
Track selection signal P output from the control signal generation circuit 13
It operates in synchronization with SW and outputs a recording audio signal at the timing of the designated track. This PCM recording circuit
The recording audio signal output from 24 is input to the common terminal of the changeover switch 29 via the amplifier 28. The changeover switch 29 has its common terminal switchably connected to the terminal H or the terminal L in response to the track selection signal PSW output from the PCM control signal generating circuit 13. The terminal L and the terminal H of the changeover switch 27 together with the changeover switch. Connected to 31 common terminals. Further, the terminal H of the changeover switch 29 is connected to the common terminal of the changeover switch 32 together with the terminal L of the changeover switch 27. The changeover switches 31 and 32 have their common terminals switched and connected to a terminal R or a terminal P by a control signal R / P output from the system controller 11, and the terminals R are connected to the rotary heads HA and HB, respectively. It

Then, in the playback mode, the rotary heads HA, HB
The signal read from the video tape is input to the amplifiers 35 and 36 via the terminals P of the changeover switches 33 and 34.
A common terminal of the changeover switches 33 and 34 is connected to the terminal P or the terminal R by the recording / reproducing signal R / P output from the system controller 11. And the above amplifier
The output signals of 35 and 36 are input to the PCM reproducing circuit 39 or the video signal reproducing circuit 40 via the changeover switches 37 and 38. The changeover switch 37 has its common terminal switched and connected to the terminal H or the terminal L by the track selection signal PSW from the PCM control signal generation circuit 13. The terminal L is connected to the amplifier 35, and the terminal H is connected to the amplifier 36. To be done.
The changeover switch 38 has a common terminal switched and connected to the terminal H or the terminal L by the head switching signal HSW. The terminal H is connected to the amplifier 35 and the terminal L is connected to the amplifier 35.
Connected to 36. Then, the PCM reproducing circuit 39
The input signal is reproduced according to the track selection signal PSW output from the CM control signal generation circuit 13 and output to the audio signal output circuit (not shown) via the output terminal 41. The video signal reproducing circuit 40 is a system controller.
A VTR / PCM signal V / P from 11 reproduces a video signal in the VTR mode and outputs it to a video signal circuit (not shown) through the output terminal 42.

The output signal of the amplifier 35 is input to the gate circuit 43. This gate circuit 43 is a PCM control signal generation circuit.
While the check timing signal CSW given from 13 is at the high level, the input signal is rounded and input to the band pass filter 44. This bandpass filter 44
M. T. S For extracting only the identification signal of, for example, 228.748 KHz, the output signal is detected by the diode 45 and then sent to the Schmitt circuit 47 via the low pass filter 46. The Schmitt circuit 47 waveform-shapes the input signal and outputs it to the 6-bit shift register 48. The check timing signal CSW and the track pulse PT output from the PCM control signal generation circuit 13 are input to the clock terminal of the shift register 48 via the AND circuit 49. Above shift register 48
Is a track pulse P input via the AND circuit 49.
The input signal is sequentially read and shifted in synchronization with T, and each bit output is output to the 6-bit latch circuit 50. Further, a head switching signal H is applied to the clock terminal of the latch circuit 50.
The control signal QR output from the SW and the system controller 11 is input via the AND circuit 51. The latch circuit 50 reads the output signal of the shift register 48 by the signal given through the AND circuit 51 and outputs it to the system controller 11. This system controller 11
Judges the unrecorded track from the latch data of the latch circuit 48, displays the judgment result on the display unit 14, and starts recording on the lowest track among the unrecorded tracks.

Next, the operation of the above embodiment will be described. When recording / reproducing video signals, attach an 8mm cassette tape,
The mode switch 1 in the key input unit 10 is switched to the VTR side. When the VTR mode is designated by the mode switch 1, the head switching signal H is output from the PCM control signal circuit 13.
The same timing as SW and the track selection signal PSW1 are output. Then, when reproducing the video signal recorded on the video tape 18, the PLAY key 4 is operated, and when recording the video signal, the PLAY key 4 and the REC key 5 are operated simultaneously. When the image signal reproducing apparatus is used, the changeover switches 31 and 32 are turned off and the changeover switches 33 and 34 are turned on by the R / P signal output from the system controller 11. Therefore, the rotary head H
The signals read from A and HB are amplified by amplifiers 35 and 36 and input to switch circuits 37 and 38. The changeover switch 37 is switch-controlled by the track selection signal PSW1 shown in FIG. 2, selects the PCM audio signal of the first track Tr1 read by the rotary heads HA, HB and inputs it to the PCM reproducing circuit 39. This PCM
The reproducing circuit 39 periodically reproduces the PCM audio signal input via the changeover switch 37 to the track selection signal PSW1 and outputs it from the terminal 41. Further, the changeover switch 38 is switch-controlled by a head changeover signal HSW, and a video signal reproducing circuit 40 outputs a video signal read from the tracks of Tr2 to Tr6 by the rotary heads HA, HB.
Output to. The video signal reproducing circuit 40 reproduces the video signal only when the VTR mode is designated and outputs it from the terminal 42.

When recording a video signal on the video tape 18, the PLAY key 4 and the REC key 5 are simultaneously operated in the VTR mode. The recording mode is designated by the above key operation, and the changeover switches 31 to 34 are changed over to the R side terminals by the R / P signal output from the system controller 11, the changeover switches 31 and 32 are turned on, and the changeover switches 33 and 34 are turned on. Turns off. Therefore, the video signal input to the terminal 21 is input to the changeover switch 27 via the video signal recording circuit 23, the amplifier 25, and the changeover switch 26. This changeover switch 27
The video signal is switched in synchronization with the head switching signal HSW, and the video signal amplified by the amplifier 25 is alternately output to the rotary heads HA and HB and recorded on the tracks of Tr2 to Tr6 of the video tape 18. At the same time, the audio signal input to the terminal 22 is switched through the PCM recording circuit 24 and the amplifier 28.
Entered in 29. The changeover switch 29 changes over in synchronization with the track selection signal PSW1 and records the PCM audio signal on the first track Tr1 of the video tape 18.

When recording / reproducing only the audio signal, an 8 mm cassette tape for recording the audio signal is mounted, the mode switch 1 is used to switch to the PCM mode, and the PCM track designating key 2 is used to select and designate a desired track. When a desired track is designated by the PCM track designation key 2, the PCM control signal generation circuit 13 outputs the track selection signals PSW1 to PSW6 according to the designated track as shown in FIG. In this state, PLAY key 4 or PLAY key 4 and REC key 5
By simultaneously operating the and, the audio signal is read or recorded for the designated track.

Next, the operation for urgently recording FM broadcast programs, etc.
This will be described with reference to the flowchart in the figure. If you want to urgently record FM broadcast programs, etc., in the state where the PCM mode is specified, the QRE in the key input unit 10
Operate the C key 3. When the QRC key 3 is operated, the system controller 11 first executes a reproducing operation for N seconds, for example, 1 to 2 seconds, and sets the QR signal to a high level as shown in step A1 of FIG. In the reproduction mode, the changeover switches 31 and 32 are turned off, the changeover switches 33 and 34 are turned on, and the data read from the rotary heads HA and HB are amplified via the changeover switches 33 and 34.
Sent to 35, 36. Then, the output signal of the amplifier 35 is input to the gate circuit 43. The gate circuit 43 opens the gate of the first track Tr1 to read from the head HA while the check timing signal CSW supplied from the PCM control signal generation circuit 13 is at a high level.
The recording data of the sixth track Tr6 is selected and output.
Then, the first track T selected by the gate circuit 43
The recording data of the first to sixth tracks Tr6 are sent to the bandpass filter 44, and the M.M.R. recorded on the PCM audio data is multiplexed as shown in FIG. T. S, that is 2
Only the 28.748 KHz identification signal is retrieved. Second
The output signal of the bandpass filter 44 in the figure is the first,
FIG. 7 shows signal waveforms when data is recorded on the second and fifth tracks Tr1, Tr2, Tr5.
Then, the identification signal output from the band pass filter 44 is detected by the diode 45 and then sent to the Schmitt circuit 47 via the low pass filter 46. Therefore, a signal of "1" (high level) or "0" signal (low level) is output from the Schmitt circuit 47 according to the identification signal recording state in the first track Tr1 to the sixth track Tr6 of the video tape 18. Is output. That is, the Schmitt circuit 47 outputs a “1” signal to the track on which the identification signal is recorded and a “0” signal to the track on which the identification signal is not recorded, and sends it to the shift register 50. To be The track pulse PT from the PCM control signal generation circuit 13 is input to the clock terminal of the shift register 50 from the PCM control signal generation circuit 13 while the check timing signal CSW is at a high level. Therefore, the shift register 48 reads the output signal of the Schmitt circuit 47 in synchronization with the track pulse PT input via the AND circuit 49, and sequentially shifts it. When the data corresponding to the first track Tr1 to the sixth track Tr6 is read into the shift register 48, the check timing signal CSW becomes low level, and the gate circuit of the AND circuit 49 is closed. Further, since the head switching signal HSW falls at the same time, the output signal of the AND circuit 51 falls, and the data held in the shift register 48 is latched by the latch circuit 50 in synchronization with the fall, and the system controller
Sent to 11. After executing the reproducing operation for N seconds as described above, the system controller 11 sets the QR signal to the low level as shown in step A2 of FIG. 4, and then stops the tape running in step A3. And
In step A4, the system controller 11 determines the presence or absence of an unrecorded track from the latch data of the latch circuit 50. For example, as described above, the first track Tr1
P on Tr1, Tr2, Tr5 in the sixth track Tr6
If the CM audio signal has already been recorded, the "1" signal is latched in the first, second and fifth bits of the latch circuit 48 as shown in FIG. Therefore, the system controller 11 can determine the recorded track and the unrecorded track based on the latch data of the latch circuit 50. In this case, the system controller 11 uses the latch circuit.
If the latch data of 50 is all "1", it is determined that there is no unrecorded track, and the process proceeds to step A5 and the display unit 1
All the recorded track display bodies 16 of 4 are driven to be displayed, and the processing is terminated. Also, the system controller 11
If it is determined in step A4 that there is an unrecorded track from the latch data of the latch circuit 50, the process proceeds to step A6 and the lowest track is designated. For example, T
If the tracks r3, Tr4, and Tr6 have not been recorded, the PCM control signal generation circuit 13 outputs the track selection signal PSW3 to specify the third track Tr3. Then, in step A7, the recorded track display 16
Among them, the display bodies corresponding to the tracks of Tr1, Tr2, and Tr5 are driven to display, and the track display body 17 corresponding to the third track Tr3 is driven to display. Next, in step A8, the PCM recording circuit 24 causes the third track T
The recording operation of the audio signal for r3 is started.
That is, the PCM recording circuit 24 performs pulse width modulation on the audio signal input to the terminal 22 and outputs the track selection signal PS.
Output in synchronization with W3. And this PCM recording circuit 2
The PCM audio signal output from 4 is amplified by the amplifier 28, and then alternately switched by the changeover switch 29 in synchronization with the track selection signal PSW3, input to the rotary heads HA and HB, and supplied to the third tape of the video tape 18. It is recorded on the track Tr3. QREC key 3 as above
When is operated, an unrecorded track is automatically detected, and the PCM audio signal is recorded on the lowest track of the unrecorded tracks.

In the above embodiment, when an unrecorded track is detected,
Although the audio signal is recorded on the lowest track, the signal recording is not limited to the lowest track, and it goes without saying that the signal may be recorded on any other track.

[Effects of the Invention] As described in detail above, according to the present invention, by operating the QREC key 3, for example, a reproducing operation is performed for 1 to 2 seconds to automatically detect an unrecorded track, and the unrecorded track is not detected. Since an audio signal is recorded by designating an arbitrary track in the recording tracks, for example, when an FM broadcast program or the like is to be urgently recorded, even if the recording state of the tape is not grasped, the empty track is surely recorded. It is possible to eliminate the inconvenience of accidentally erasing important recordings.

[Brief description of drawings]

The drawings show one embodiment of the present invention. FIG. 1 is a block diagram showing a circuit configuration, FIG. 2 is a timing chart for explaining the operation, and FIG. 3 is a PC in a video tape.
FIG. 4 is a diagram showing the format of the M multi-track, and FIG. 4 is a flow chart showing the operation when performing emergency recording. 1 ... Mode switch, 2 ... PCM track designation key, 3 ...
QREC key, 4 ... PLAY key, 5 ... REC key, 10 ...
Key input section, 11 ... System controller, 12 ... Display drive circuit, 13 ... PCM control signal generation circuit, 14 ... Display section, 15 ...
Track display section, 16 ... Recorded track display body, 17 ... Playing track display body, 18 ... Video tape, 19 ... Track,
21, 22 ... Recording signal input terminal, 23 ... Video signal recording circuit, 24
... PCM recording circuit, 25, 28, 35, 36 ... Amplifier, 26, 27,
29, 31 to 34, 37, 38 ... Changeover switch, 39 ... PCM reproducing circuit, 40 ... Video signal reproducing circuit, 43 ... Gate circuit, 44 ... Bandpass filter, 46 ... Lowpass filter, 47 ... Schmidt circuit, 48 ... Shift Register, 50 ... Latch circuit.

Claims (1)

[Claims] 1. A track is divided into a plurality of tracks,
In the PCM multi-track system in which a signal is time-compressed for each track and PCM-recorded, and an identification signal of a predetermined frequency is frequency-multiplex-recorded, a means for temporarily making a reproduction state in response to an operation of a specific key, A means for detecting the recording state of each track of the tape based on the presence or absence of the identification signal, and a means for selecting any of the unrecorded tracks in accordance with the detection result of this means and controlling the selected track to be recordable. A recording track control device characterized by the above.