JPH0664836B2 - Recording circuit of tape recorder - Google Patents

Description

TECHNICAL FIELD The present invention relates to a recording circuit of a tape recorder, and more particularly to a recording circuit suitable for a tape recorder used as a memo.

(B) Conventional Technology Tape recorders for recording audio signals on magnetic tapes are widespread, but such tape recorders are often used for recording the contents of meetings and lectures. When performing such a recording operation, the length of the magnetic tape is often insufficient, and the cause thereof is that the magnetic tape runs even though there is no audio signal to be recorded.
As a technique for improving such a point, there is a technique in which an electric motor is rotationally driven to run a magnetic tape only when there is a recording signal obtained from a microphone. As such a technique, for example, Japanese Utility Model Publication No. 56-43 Have been disclosed in.

(C) Problems to be Solved by the Invention According to the technique of the above-mentioned publication, wasteful running of the magnetic tape can be surely eliminated and the magnetic tape can be effectively used, but there are the following problems. That is, in such a recording operation, since the contents of the conference or the lecture are all recorded on the magnetic tape, it is necessary to reproduce the signal recorded on the magnetic tape only for the time required for the recording operation. And, an important part of such a recorded signal is generally very small, and such a part is often recorded during a conference or a lecture. Therefore, it is wasteful in time to reproduce all of the signals thus recorded. The present invention is
An object of the present invention is to provide a recording circuit that improves such a point.

(D) Means for Solving the Problems The recording circuit of the present invention stores a signal obtained from a microphone as a digital signal for a predetermined time and reads the signal after a predetermined time, and a memory circuit for reading the signal. It is composed of a voice conversion circuit for converting the digital signal thus converted into an analog signal and for inputting the analog signal to a recording amplifying circuit.

(E) Function The present invention converts a signal obtained from a microphone into a digital signal and stores it in a memory circuit for a predetermined time, and after a predetermined time, converts a signal read from the memory circuit into an analog signal and records it on a magnetic tape. It is something that is done.

(F) Embodiment The illustrated circuit is an embodiment of the recording circuit of the present invention.
In the figure, (1) is a microphone that converts an acoustic signal into an electric signal, (2) is a microphone amplifier circuit that amplifies the signal when a signal obtained from the microphone (1) is input, and (3) is usually Is a selection switch for selecting between the recording operation and the memory recording operation of the first terminal (3a), the second terminal (3b) and the common terminal (3c) connected to the output terminal of the microphone amplifier circuit (2). )
Is equipped with. (4) is a recording amplifier circuit for inputting a signal through the selection switch (3) and amplifies the signal, and (5) is a circuit to which the signal amplified by the recording amplifier circuit (4) is applied. A magnetic head that records signals on magnetic tape. (6) is a battery, (7) is an electric motor that drives the magnetic tape to run, and (8) is a power switch that is inserted and connected in a power supply path to the electric motor (7) for operations such as recording and reproduction. Is configured to be closed when is performed. Reference numeral (9) is a first voice conversion circuit which receives the signal amplified by the microphone amplification circuit (2) and converts the signal into a digital signal, and an output terminal (10) for outputting the converted digital signal. ) Is provided. Reference numeral (11) is a memory circuit for receiving a signal converted into a digital signal by the first voice conversion circuit (9) and storing the signal for a predetermined time, and an output terminal of the first voice conversion circuit (9). A write terminal (12) and a read terminal (13) connected to (10) are provided. (14) is the memory circuit (1
1) is a second audio conversion circuit which receives the digital signal read from the same and converts the digital signal into an analog signal, and the output terminal (15) of the analog signal is the second terminal (3) of the selection switch (3). Connected to 3b). (16)
Is an interlocking switch that is switched in conjunction with the selection switch (3), and (17) is an operation that is controlled by the interlocking switch (16) and the interlocking switch (16) is interlocked with the switching of the selection switch (3). Is a control circuit for performing a control operation for a memory recording operation when switched to the opposite side of the state shown in the figure. The first voice conversion circuit (9), the memory circuit (11) and the second voice conversion circuit (1
It has the function of controlling the operation of 4). (18) is a memory recording switch that is closed during memory recording operation and opened during memory recording release operation, and (19) is controlled by the control circuit (17) and operates to the electric motor (7). A motor control circuit for controlling the opening / closing operation of a control switch (20) inserted and connected in a power supply path, the control circuit (1) by switching the interlocking switch (16).
By the control operation of 7), the control switch (20) is opened, and when the memory recording switch (18) is closed, the control switch (20) is closed. (21) is an operation state when the memory recording switch (18) is switched from the closed state to the open state by the memory recording release operation, and is a holding signal for a predetermined time, that is, a storage time of the memory circuit (11). Is a timer circuit for outputting the control switch (20) while keeping the control switch (20) closed. In such a circuit configuration, the time stored in the memory circuit (11) is set to about 8 seconds when using a 256 Kbit RAM, for example. The memory operation is controlled by the control circuit (1
Although controlled by 7), the signals input to the write terminal (12) are stored in the memory circuit (11) one after another and output to the read terminal (13) one after another after a predetermined time, that is, 8 seconds. Is configured. The recording circuit of the present invention is configured as described above, and its operation will be described below.

First, a normal recording operation in which the selection switch (3) and the interlocking switch (16) are in the illustrated state will be described. When the recording operation is performed in the state shown in the figure, the drive mechanism of the magnetic tape enters the recording operation state, the power switch (8) is closed, and the electric power is supplied to the electric motor (7) to stop the recording operation of the magnetic tape. Drive operation is performed.
In addition, power is supplied to the microphone amplification circuit (2) and the recording amplification circuit (4), and the tape recorder enters the recording operation state. The recording signal converted into an electric signal by the microphone (1) in the recording operation state is input to the microphone amplifier circuit (2) and amplified. The recording signal amplified by the microphone amplifier circuit (2) is input to the recording amplifier circuit (4) through the selection switch (3). The recording signal input to the recording amplifier circuit (4) is amplified and then applied to the magnetic head (5) to be recorded on the magnetic tape by the magnetic head (5). When in such a recording operation state, the memory circuit (11), the first audio conversion circuit (9) and the second audio conversion circuit (14) are inoperative. Although the normal recording operation is performed in this manner, the memory recording operation using the memory circuit (11) will be described next.

Such a memory recording operation is performed by first switching the selection switch (3) to the opposite side of the state shown and performing the above-mentioned normal recording operation. When the selection switch (3) is switched to the opposite side of the illustrated state, the interlocking switch (16) is switched to the opposite side of the illustrated state and a signal output to the output terminal (15) of the second audio conversion circuit (14). Is applied to the input terminal of the recording amplification circuit (5) through the selection switch (3). When the interlock switch (16) is switched to the opposite side to the state shown in the figure, the control circuit (17) enters a state of performing a control operation for the memory recording operation, and the control switch (20) is operated by the operation of the motor control circuit (19). ) Is released. Further, the first voice conversion circuit (9), the memory circuit (11) and the second voice conversion circuit (14) are activated by the action of the control circuit (17), and the first voice conversion circuit (9) The analog circuit converts the analog signal into a digital signal, the memory circuit (11) stores the memory signal, and the second voice conversion circuit (14) converts the digital signal into an analog signal. That is,
In such a state, the recording signal converted into an electric signal by the microphone (1) is input to the microphone amplification circuit (2) and amplified, and then input to the input terminal of the first audio conversion circuit (9). It The recording signal which is an analog signal input to the first voice conversion circuit (9) is converted into a digital signal and output to the output terminal (10). The digital signal output to the output terminal (10) is input to the write terminal (12) provided in the memory circuit (11) and stored in the memory circuit (11). The signal stored in the memory circuit (11) is output to the read terminal (13) after a predetermined time, that is, 8 seconds. The read terminal (1
The digital signal output to 3) is the second audio conversion circuit (1
It is input to 4), converted into an analog signal which is the original signal, and output to the output terminal (15). The recording signal output to the output terminal (15) is input to the recording amplifying circuit (4) through the selection switch (3), but the recording signal is delayed for 8 seconds from the time when it is input to the microphone (1). And is input to the recording amplifying circuit (4). Then, in such a state, the control switch (20) is opened, the power supply to the electric motor (7) is cut off, and the running drive operation of the magnetic tape is not performed, so that the magnetic head (5) records on the magnetic tape. No action is taken. In such a state, if there is a message to be noted during the conference, the memory recording switch (18) may be closed.
When the memory recording switch (18) is closed, the control switch (20) is closed by the operation of the electric motor control circuit (19) by the control operation of the control circuit (17). When the control switch (20) is closed, power is supplied to the electric motor (7), and the magnetic tape is driven by the rotation of the electric motor (7). Therefore, the output terminal of the second audio conversion circuit (14) ( 1
The recording signal output to 5) and input to the recording amplifier circuit (4) is recorded on the magnetic tape by the magnetic head (5). The recording signal recorded on the magnetic tape when the memory recording switch (18) is closed is not the signal input to the microphone (1) when the recording switch (18) is closed. Since the signal is input a few seconds ago, the user's last-requested utterance he wishes to make a note of is recorded on the magnetic tape. In this way, the signal delayed by the memory circuit (11) is recorded on the magnetic tape by the magnetic head (5), but when the content of the utterance does not need to be recorded, the memory recording switch (18 ) Should be opened. When the memory recording switch (18) is opened, the timer circuit (21) operates and outputs a holding signal for the memory operation time of the memory circuit (11), that is, 8 seconds, so that it is controlled by the motor control circuit (19). The switch (20) is held in the closed state.
Therefore, during that time, the magnetic tape is driven to run, and all the signals stored in the memory circuit (11) when the memory recording switch (18) is opened are recorded on the magnetic tape. Then, when a predetermined time, that is, 8 seconds elapses after the memory recording switch (8) is opened, the holding operation by the timer circuit (21) is completed and the control switch (20) is opened. When the control switch (20) is opened, the electric power supply to the electric motor (7) is cut off, the running of the magnetic tape is stopped, and the tape recorder enters the recording standby state. While in the recording standby state, the magnetic tape stops running, but the first audio conversion circuit (9), the memory circuit (11) and the second audio conversion circuit (14) perform conversion operation and storage operation, respectively. By performing the closing operation and the opening operation of the memory recording switch (18) repeatedly, it is possible to select only the necessary information during the conference or lecture and record it on the magnetic tape.

In this embodiment, the storage operation time by the memory circuit (11) is set to 8 seconds, but the storage operation time can be lengthened by increasing the capacity of the memory used in the memory circuit (11). The control time of the timer circuit (21) can be set longer than the storage time of the memory circuit (11).

(G) Effect of the Invention The recording circuit of the present invention selects the normal recording operation and the memory recording operation by switching the selection switch, and when in the memory recording operation state, the magnetic tape by the memory recording start operation of the memory recording switch. Since a signal delayed for a predetermined time by the storage operation of the memory circuit is recorded on the magnetic tape by the start of running, that is, the recording signal obtained from the microphone is delayed for the predetermined time and recorded on the magnetic tape. The user has the advantage of being able to listen to the signal to be recorded on the magnetic tape before recording, and thus to select and record the required signal.

Further, according to the present invention, the running of the magnetic tape is stopped at least after the storage time of the memory circuit elapses during the memory recording canceling operation by switching the memory recording switch, that is, during the memory recording canceling operation. Since the running of the magnetic tape is stopped after the storage time of the memory circuit has elapsed without immediately stopping, the signal stored in the memory circuit, that is, the signal heard before the release operation is all recorded on the magnetic tape. Therefore, recording mistakes can be prevented.

Further, the present invention is provided with a selection switch for selecting a normal recording operation which does not use a memory circuit and a memory recording operation which uses a memory circuit, so that two different recording operations can be selectively performed. Therefore, the user can select the recording operation according to different recording conditions such as recording his own voice or recording the contents of the lecture, and the present invention is a tape recorder used instead of a memo. When it is carried out, it is very effective.

[Brief description of drawings]

The circuit shown is an embodiment of the recording circuit of the present invention. Description of main figure numbers (1) …… Microphone, (2) …… Amplification circuit for microphone, (3) …… Selection switch, (4) …… Amplification circuit for recording, (5) …… Magnetic head, ( 7) ... motor, (9) ... first voice conversion circuit, (11) ... memory circuit, (14) ... second voice conversion circuit, (17) ... control circuit, (18) ... memory Recording switch, (19) …… motor control circuit, (20) …… control switch, (21) …… timer circuit.

Claims (1)

[Claims] 1. A microphone amplifier circuit for amplifying a signal obtained from a microphone, a selection switch for selecting a normal recording operation and a memory recording operation, an operation state during a memory recording operation, and an amplifier circuit for the microphone. A first audio conversion circuit for converting the output signal into a digital signal, and a digital signal converted by the first audio conversion circuit while being in an operating state during a memory recording operation, stored for a predetermined time, and after the predetermined time, the signal A second audio conversion circuit for converting a signal read from the memory circuit into an analog signal when the memory circuit is read out, a second voice conversion circuit for converting the signal read from the memory circuit into an analog signal, and a normal recording operation during the normal recording operation. The signal output from the microphone amplifier circuit is input and the memory recording operation is performed. At this time, a recording amplifier circuit to which a signal output from the second audio conversion circuit is input, a magnetic head to which the signal amplified by the recording amplifier circuit is applied and a signal is recorded on a magnetic tape, and a recording operation At the time of the memory recording operation, an electric motor for driving the magnetic tape to run, a control circuit for controlling the operation of the first audio conversion circuit, the memory circuit, the second audio conversion circuit and the electric motor while being in an operating state during the memory recording operation. A memory recording switch that can be switched, and when the normal recording operation and the memory recording operation are selected by switching the selection switch and the memory recording operation state is set, the magnetic tape of the magnetic tape by the memory recording start operation of the memory recording switch is selected. The signal delayed by the memory circuit for a predetermined time when the vehicle started running was recorded on the magnetic tape. Tape recorder recording circuit and is characterized in that so as to stop the running of the magnetic tape after storage time of the switching memory recording release operation at least the memory circuit according to the memory recording switch.