JPH0316701B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a magnetic recording and reproducing device, and its purpose is to generate a large number of control signals using signals from a constant frequency signal generation source, record them on a recording medium, and use the signals to generate a large number of control signals on a recording medium. The object of the present invention is to easily realize automatic switching of noise reduction circuits, equalizers, etc., cueing using an absolute address system, etc.

Today's magnetic recording and reproducing devices are equipped with various noise reduction devices, and the number of models that are equipped with multiple noise reduction devices (hereinafter referred to as NR system) in one device is increasing. On the other hand, most of these multiple NR systems are not compatible, so the NR system used during recording and playback must match, and tapes recorded using multiple NR systems of different types must be matched. When playing back alternately tapes recorded without using the NR system or the NR system, the NR system must be switched each time, and this switching operation is quite troublesome. The present invention eliminates the complexity of such operations, and in the above case, a control signal corresponding to each NR system is recorded in the non-signal area immediately before the information recording area of the tape, and the control signal corresponding to each NR system is recorded during playback. By detecting this signal, the NR system is automatically switched.

In addition, some conventional magnetic recording and reproducing devices have a function to quickly insert the required information recording section, a so-called song selection function, but this song selection function is a skipping song selection function that advances the number of songs forward from the current song. Most of the songs are selected by specifying whether to go back or backwards, and few songs are selected by specifying the absolute address from the beginning of the tape. There was the inconvenience of not having to do so. Even in such a case, the present invention records a control signal that specifies the absolute address of the song after the above-mentioned NR system switching control signal with a no-signal section in between, and when playing back, the specified address is recorded from an arbitrary tape position. It becomes possible to select a song by scanning.

As described above, the present invention enables various functions of a magnetic recording/reproducing device to be automatically controlled by control signals recorded on a recording medium.One embodiment of the present invention will be described below regarding automatic NR system switching and absolute control. This will be explained with reference to the drawings of a magnetic recording and reproducing device having two functions of selecting music according to the local number.

Figure 1 shows the recording system of the device of this embodiment.
1 is a constant frequency signal generation source that continuously generates a signal of a constant frequency, and 2 is a gate circuit that opens and closes every t seconds for a certain period of time to intermittently transmit the signal from the signal generation source 1 to the next stage. , 3 is a no-signal detection circuit configured to generate a pulse at the moment the output from the gate circuit 2 changes to no signal, in other words, to detect the falling part of an intermittent signal; 4 is a no-signal detection circuit from the no-signal detection circuit 3; A counter circuit that counts the output pulses of and outputs an output corresponding to the counted number from the output terminal, 5 and 6 determine which circuit in the subsequent stage the output of the gate circuit 2 is transmitted according to the output from the counter circuit 4. A switching circuit for selecting, 5 is L
6 is for the R channel. 7 is a control signal generation circuit for NR system switching including two switches S1 and S2, and 8 is S3.
A control signal generation circuit for absolute address selection includes nine switches S11, 9 and 10 are recording heads for the L channel and R channel, respectively. To simplify the explanation, the oscillation circuit for the recording amplifier bias current in normal recording, the switching switch between these and the above-mentioned system, etc. are omitted. How the control signal is recorded on the tape via the head using the configuration shown in FIG. 1 will be explained.

First, the gate circuit 2 starts opening and closing operations by operating a control signal recording start switch (not shown) in the gate circuit 2. When there is no signal for the first time, the no-signal detection circuit 3 detects this and outputs a pulse. The counter circuit 4 receives the signal and outputs it from the output terminal 1, drives the switching circuits 5 and 6, and transmits the output from the gate circuit 2 from the output terminal 1 to the control signal generation circuit for switching the NR system. In this example, to simplify the explanation, it is assumed that three types of NR systems are switched, and a manual NR system switching switch (not shown) is used.
Outputs corresponding to the respective NR systems (not shown) are transmitted to the recording heads 9 and 10 by the combination of opening and closing of S1 and S2 in conjunction with the NR system. That is,
When switches S1 and S2 are selectively turned on, a signal is recorded in only one of the L channel and R channel, and when both switches S1 and S2 are turned on, a control signal is recorded in both L and R channels. This allows us to distinguish between three types of NR systems.

The second no-signal that comes next is also input to the counter circuit 4 through the same process as the first no-signal described above, and is input to the counter circuit 4.
is output from the output terminal 2 and the switching circuits 5 and 6
The output from the gate circuit 2 is transmitted from the output terminal 2 to the music selection control signal generation circuit 8. At this time, with only a single control signal, 3
Since only one type of signal can be created, nine types of signals are created by combining with the control signal to be output next. In other words, for the third non-signal that comes in third place, the counter circuit 4 outputs from the output terminal 3, drives the switching circuits 5 and 6, and outputs from the output terminal 3, but the three types of outputs and the second control Nine types of signals are created by combining the three types of output signals. (See FIG. 2) When combined with the fourth signal, 27 types of signals can be created, but in this embodiment, for simplicity of explanation, only 9 types are used. Recording of the control signal is completed in the above manner. In this embodiment, since the control signal is up to the third signal, the counter circuit 4 is assumed to be a quaternary counter and is reset when there is no fourth signal.

Next, the reproduction system will be explained using FIG.
11 and 12 are playback heads for the L channel and R channel, respectively, 13 and 14 are playback amplifiers, 15 and 16 are leveling circuits for converting the AC waveform to DC level, and 17 is the output for both the L and R channels. 18 is a no-signal detection circuit similar to the no-signal detection circuit 3 in the recording system, and 19 is also a counter circuit 4 in the recording system.
20 and 21 are switching circuits similar to switching circuits 5 and 6 in the recording system, and 22 is a logic for synthesizing a control signal for switching the NR system from the signals of both the L and R channels. Similarly, the circuit 23 is a logic circuit for combining the outputs of both channels to synthesize a control signal corresponding to the absolute address of the song. This logic circuit 23 is the previous logic circuit 22
It consists of two sets of circuits having the same configuration as , and its output is held until the fourth no-signal portion is detected. 24 is a logic circuit for combining the outputs of the two sets of logic circuits of the logic circuit 23 to generate nine types of control signals. How the control signals recorded on the tape are reproduced to perform the NR system switching and song selection functions under the above configuration will be explained along the signal path. Playback heads 11, 12, playback amplifier 1
After the playback control signal that has passed through steps 3 and 14 is converted to a DC level by leveling circuits 15 and 16, an OR circuit 17 and a no-signal detection circuit 18 detect the moment when the outputs of both channels become no signal. is detected. When the first no-signal is detected, the counter circuit 19 receives the output pulse of the no-signal detection circuit 18 and outputs it from the output terminal 1, drives the switching circuits 20 and 21, and passes through the leveling circuits 15 and 16. The first control signal is output from the output terminal 1 and transmitted to the logic circuit 22 for synthesizing the NR system switching signal. The logic circuit 22 corresponds to the signal recording time, and when only the L channel is output, the first NR system is used, when only the R channel is output, the second NR system is used, and when both channels are output, the first NR system is used. NR system switching circuit 25 to switch to the 3rd NR system.
Output to. In other words, when input is applied to input terminal 1 of the NR system switching circuit 25, it is the third NR system input terminal, and when it is input to the third NR system input terminal 2, it is the first input terminal.
When the NR system input terminal 3 is selected, the system switches to the second NR system.

In this way, the first control signal
After the switching of the NR system is completed, the second no-signal portion is reproduced, which is detected by the no-signal detection circuit 18 in the same manner as the first no-signal portion and outputs a pulse to the counter circuit 19. is transmitted, the counter circuit 19 drives the switching circuits 20 and 21 from the output terminal 2, and the flat circuits 15 and 1
6 is transmitted from output terminal 2 to any one of output terminals 1 to 3 of logic circuit 23. This output is not a pulse and has the property of being held even if there is no output from the tape, but is reset when the second no signal is detected. Next, the third no-signal is connected to the switching circuit 2 through the same process as the second no-signal.
0 and 21, and transmits the third control signal to the output terminals 4 to 6 of the logic circuit 23. This output and the output according to the second control signal are input to the logic circuit 24, and the music selection is performed by comparing the output with the absolute address designated at the time of music selection. Note that the logic circuits 24 and 25 correspond to the signal generation circuits 8 and 7 during signal recording. Control signal playback is completed as described above, but if the tape is recorded as shown in FIG. 4, the selected NR system is the second NR system, and the address at the time of song selection is It is “8”. Fourth
In the figure, 26 is the end of previous information, so-called the previous song, 27 is the start of the next song, 28, 29, and 30 are first, second, and third control signals, and 31 is a no-signal portion.

In this way, the device of this embodiment can be realized with a relatively simple configuration by simply adding a conventional no-signal detection circuit, a counter, a logic circuit with a simple configuration, etc. to a normal recording/reproducing device. However, it can be used in a wide range of ways, including automatic NR system switching and absolute song address selection, as well as fine adjustment of the playback equalizer, recording bias according to the type of individual tape, and automatic equalizer setting.

As explained above, the magnetic recording/reproducing apparatus of the present invention includes a counter circuit for the output of the no-signal detection circuit in the selection circuit that selectively transmits a constant frequency signal to a plurality of recording lines for recording on a recording medium. A large number of control signals corresponding to multiple functions such as control information, such as the type of noise reduction device used and absolute address information of the information signal to be recorded, can be efficiently placed on the recording medium.
On the other hand, since the detection circuit that detects these reproduced control signals includes a counter circuit for the no-signal detection circuit, these control signals are discriminated by the discrimination circuit and the necessary operation control is performed, so that the necessary operation is not detected during reproduction. Various operations to be performed, such as adjusting the type of noise reduction device to the same type as that used during recording, and selecting a station using absolute address information, can be automated, and the operability of the device can be greatly improved. Can be done.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of the recording system of a magnetic recording/reproducing device according to an embodiment of the present invention, FIG. 2 is a diagram for explaining its operation, FIG. 3 is a block diagram of the reproducing system of the same device, and FIG. The figure shows an example of a recording pattern on a tape. DESCRIPTION OF SYMBOLS 1... Constant frequency signal generation source, 2... Fixed time interval switching circuit, 3... No signal detection circuit, 4...
... Counter circuit, 5, 6 ... Switching circuit,
7...Switch group for creating NR system switching signal, 8...Switch group for creating music selection signal, 9, 10
... Recording head, 11, 12 ... Playback head, 1
3, 14... Reproduction amplifier, 15, 16... Leveling circuit, 17... OR circuit, 18... No signal detection circuit, 19... Counter circuit, 20, 21... Switching circuit, 22... NR System switching logic circuit, 23, 24... Music selection logic circuit, 25
...NR system switching circuit, 26...End of previous song, 27...Start of next song, 28...First control signal, 29...Second control signal, 30...
...Third control signal, 31...No signal portion.

Claims (1)

[Claims] 1. In a magnetic recording/reproducing device having a plurality of magnetic recording channels, the recording side includes a first switching circuit that switches on/off a signal from a constant frequency signal generation source that generates a signal of a constant frequency at constant time intervals; a no-signal detection circuit that detects the falling part of the intermittent signal output from the switching circuit;
A counter circuit for counting the output from the no-signal detection circuit, and a second switching circuit for selecting which circuit in the subsequent stage the output from the first switching circuit is transmitted according to the output from the counter circuit.
It is equipped with a switching circuit and a plurality of control signal generation circuits each having a group of operation switches provided after the second switching circuit, and configured to record a control signal according to the operation of the group of operation switches at the time of recording. On the side, there is a no-signal detection circuit that detects the falling part of the reproduced signal, a counter circuit that counts the output from this detection circuit, and a transmission of the reproduced signal according to the output from this counter circuit. a third switching circuit that determines the output path; a detection means that detects whether or not the constant frequency signal is output, which is provided on a plurality of reproduction lines downstream of the third switching circuit; A magnetic recording device is equipped with a discrimination circuit that logically processes the output of the switching circuit to discriminate the operated switch of the control signal generation circuit during recording, and is configured to perform desired operation control using the output of the discrimination circuit during playback. Recording and playback device.