JPH0690770B2 - Tape recorder - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to a tape recorder having at least two decks and capable of recording a reproduction signal of one deck on the other deck, and particularly The present invention relates to a tape recorder in which a single noise reduction circuit can be shared by individual decks.

(B) Conventional Technology A tape recorder provided with two decks in a single cabinet, that is, a so-called double-deck type tape recorder is known. As such a tape recorder, for example, there is one described in JP-A-52-132814, which has a dubbing function of recording the reproduction signal of one deck on the other deck, and the reproduction of one deck. It is easy to use because it can have a continuous playback function that automatically starts playing the other deck when it is finished, and it is currently in wide use.

On the other hand, many tape recorders have a noise reduction circuit that reduces noise of the magnetic tape such as hiss noise included in a reproduction signal when the tape recorder is reproduced. The noise reduction circuit reduces the noise of the magnetic tape by performing a recording process of compressing the recording signal during recording and a reproducing process of expanding the reproduction signal during reproduction. A typical example of the noise reducing circuit is the noise reduction circuit. There is a Dolby method.

By the way, in the case of providing the noise reduction circuit in the double-deck type tape recorder, a popular tape recorder adopts a method in which a single noise reduction circuit is shared by two decks in terms of cost. FIG. 2 shows such a double-deck type tape recorder. (1) is the first magnetic head for reproduction of the first deck, (2) is reproduction by the first magnetic head (1). A first reproduction amplifier for amplifying a reproduction signal, (3) a second magnetic head for recording and reproduction of the second deck, and (4) a first amplification circuit for amplifying a reproduction signal reproduced by the second magnetic head (3). 2 playback amplifier, (5) Dolby type noise reduction circuit to reduce the noise of the magnetic tape, (6) a function switch to select the source signal to be recorded on the second deck, (7) a power amplifier (8) and An output circuit comprising a speaker (9) for monitoring a source signal selected by the function switch (6) , and (10) a second output circuit using the source signal selected by the function switch (6) as a recording signal. Recording amplifier for supplying to the magnetic head (3), and (11) to (13) A switching switched recording and reproducing switch from P (reproduction) side by recording operation of the second deck R (recording) side.

The noise reduction circuit (5) has a recording processing means for performing recording processing for noise reduction during recording, and a reproduction processing means for performing reproduction processing for noise reduction during reproduction. The recording processing means is for reducing noise by the control signal applied to the terminal (14) when the manual noise reduction switch provided on the front panel of the tape recorder is turned on and the second deck is in the recording state. It is made to operate,
The reproduction processing means is configured to perform an operation for noise reduction when the noise reduction switch is turned on and the second deck is not in the recording state. The signal that has passed through the recording processing means is output from the first output terminal (5a) of the noise reduction circuit (5), and the signal that has passed through the reproduction processing means (2a) is the second output terminal of the noise reduction circuit (5) ( It is designed to be output from 5b).

In the above device, when reproducing the magnetic tape on the first deck, first, the function switch (6) is switched to the terminal (6a) at the tape position, and the reproducing operation on the first deck is performed. Then, the reproduction of the magnetic tape is started by the first magnetic head (1). Here, the recording / reproducing switches (11) to (13) are the second
Since the deck is stopped, the movable contact piece is located on the P (playback) side. Therefore, the reproduction signal reproduced by the first magnetic head (1) is generated by the first reproduction amplifier (2) and the recording / reproducing switch (1
2), noise reduction circuit (5) playback processing means, recording / playback switch
Output circuit via (13) and function switch (6)
It is supplied to (7) and is emitted from the speaker (9) to achieve reproduction on the first deck. And in this case, if the magnetic tape has been subjected to a recording process for noise reduction,
Turn on the noise reduction switch to activate the noise reduction circuit.
If the magnetic tape does not have a recording process for noise reduction, turn off the noise reduction switch if the reproduction process means (5) performs a reproduction process for noise reduction.
Correct reproduction can be performed in both cases by using the reproduction processing means as a simple linear amplifier without operating it.

When playing back the magnetic tape on the second deck, the first
Function switch as in the case of deck playback
Switch (6) to the terminal (6a) to which the reproduction signal of the deck is supplied, and perform the reproduction operation of the second deck. Also in this case, since the movable contact pieces of the recording / reproducing switches (11) to (13) are located on the P side, the reproduction of the magnetic tape is started by the second magnetic head (3) and the reproduction signal is changed to the second After going through the playback amplifier (4),
The output circuit (7) is supplied in the same manner as in the case of the reproduction of the first deck, and the reproduction of the second deck is achieved. Then, as in the case of the reproduction of the first deck, by properly turning on / off the noise reduction switch, it is possible to correctly reproduce both the magnetic tape on which the recording processing for noise reduction is applied and the magnetic tape on which the recording processing is not applied. Can be done.

Next, when recording a magnetic tape with the second deck, when recording a source signal other than the playback signal of the first deck, set the function switch (6) to the source signal you want to record, and the playback signal of the record player It is switched to the terminal (6b) supplied, the terminal (6c) supplied with the received signal of the tuner, or the terminal (6d) supplied with the reproduction signal of the CD player. Then, the recording operation of the second deck is performed. Then, the recording / reproducing switches (11) to (13) have a movable contact R (recording).
Switch to the side. Therefore, the function switch
The source signal selected in (6) is supplied to the output circuit (7) , and also the noise reduction circuit (5) is passed through the recording / playback switch (12).
Is supplied to. The source signal supplied to the output circuit (7) is emitted by the speaker (9) and monitored.
Further, at this time, the source signal supplied to the noise reduction circuit (5) because the second deck is in the recording state is supplied to the first output terminal (5a) via the recording processing means of the noise reduction circuit (5). Output from the recording amplifier and supplied to the recording amplifier (10).
The bias current is superimposed at (10) and is supplied to the second magnetic head (3) as a recording signal. Therefore, recording is performed on the magnetic tape loaded in the second deck, and recording in the second deck is achieved. Then, in this case, when the noise reduction switch is turned on, the recording processing means of the noise reduction circuit (5) becomes operational, so the recording signal subjected to the recording processing for noise reduction is recorded on the magnetic tape. When the noise reduction switch is turned off, the recording processing means does not operate and becomes a mere linear amplifier, so that the recording signal of the source signal as it is without the recording processing for noise reduction is recorded on the magnetic tape.

Also, when recording the playback signal of the first deck on the second deck, that is, when dubbing, the function switch
(6) is switched to the terminal (6a) to which the reproduction signal of the deck is supplied, the recording operation of the second deck is performed, and the reproduction operation of the first deck is performed. Then, since the recording / reproducing switches (11) to (13) switch the movable contact to the R side for the recording operation of the second deck,
The reproduction signal reproduced by the first magnetic head (1 ) is supplied to the output circuit (7) via the first reproduction amplifier (2), the line amplifier (15), the recording / reproducing switch (13) and the function switch (6). And the noise reduction circuit via the recording / playback switch (12).
Supplied to (5). The reproduction signal of the first deck supplied to the output circuit (7) is output by the speaker (9) and monitored. At this time, since the second deck is in the recording state, the reproduction signal of the first deck supplied to the noise reduction circuit (5) is transferred to the first signal through the recording processing means of the noise reduction circuit (5). It is output from the output terminal (5a), and the recording amplifier (1
0), and a bias current is superposed on the recording amplifier (10) and supplied to the second magnetic head (3) as a recording signal. Therefore, the first magnetic tape loaded in the second deck
The playback signal of the deck is recorded, and the dubbing recording is achieved.

(C) Problems to be solved by the invention However, when performing the dubbing, the noise reduction circuit (5) is used for recording the second deck, that is, the noise reduction circuit (5) recording. Since the processing means is in a state of being used, when the magnetic tape recorded with the recording signal subjected to the recording processing for noise reduction is reproduced on the first deck, the reproduction signal is the noise reduction circuit (5). It has a drawback that it is directly supplied to the output circuit (7) without passing through and the correct reproduced sound cannot be obtained from the speaker (9). Further, at this time, if the noise reduction switch is turned on, there is a drawback that a recording signal that has been subjected to recording processing twice for noise reduction is recorded on the magnetic tape loaded in the second deck. . Further, since the noise reduction circuit (5) is shared by the first and second decks, it is necessary to connect the output terminals of the first and second reproduction amplifiers (2) and (4) having low output impedance. , The first and second reproduction amplifiers (2) and (4)
Since the resistors (16) and (17) are inserted between the output terminals of, the resistors (16) and (17) serve as loads of the first and second reproduction amplifiers (2) and (4), First and second reproduction amplifiers (2) and
There is a drawback that the reproduced signal from (4) is attenuated while reaching the input end of the noise reduction circuit (5).

(D) Means for Solving the Problems The present invention has been made in view of the above points, and when the input signal of the output circuit is switched to the second position when switched to the first position. The first changeover switch for supplying the reproduction signal of the first deck to the noise reducing circuit when the reproduction signal of the first deck is switched to the third position, and the first changeover switch of the first deck when the reproduction signal is changed to the first position. A second changeover switch is provided for supplying the output signal from the recording processing means of the noise reduction circuit to the recording amplifier of the second deck when the reproduction signal is switched to the second position.

(E) Operation In the present invention, the reproduction signal of the first deck is supplied to the output circuit via the noise reduction circuit when the first deck is in the reproduction state and the second deck is in the recording state in the dubbing state. At the same time, when the first deck is not in the reproduction state and the second deck is in the recording state so that the reproduction signal is directly supplied to the recording amplifier of the second deck, the source signal is transmitted through the noise reduction circuit. In addition to being supplied to the recording amplifier of the second deck, the first and second changeover switches are switched so that the source signal is directly supplied to the output circuit.

(F) Embodiment FIG. 1 shows an embodiment of the present invention. (18) is a first magnetic head for reproduction of the first deck, (19) is reproduction by the first magnetic head (18). A first reproducing amplifier for amplifying the reproduced signal reproduced, (20) a second magnetic head for recording and reproducing of the second deck, (21) amplifying a reproduced signal reproduced by the second magnetic head (20) The second reproduction amplifier (22) is provided with a recording processing means for performing recording processing for noise reduction during recording and a reproduction processing means for performing reproduction processing for noise reduction during reproduction, and a signal via the recording means is provided. Is output from the first output terminal (22a), and the signal passed through the reproduction processing means is output to the second output terminal (22a).
b) output Dolby noise reduction circuit, (2
3) the playback signal of the first or second deck is the first terminal (23
In a), the playback signal of the record player is the second terminal (23b)
In the receiving signal of the tuner third terminal (23c), the reproduced signal of the CD player is supplied to the fourth terminal (23d), the function switch for selecting the source signal to be recorded in the second deck, (24) Power An output circuit consisting of an amplifier (25) and a speaker (26) for monitoring the source signal selected by the function switch (23) , and (27) recording the source signal selected by the function switch (23). A recording amplifier for supplying the second magnetic head (20) as a signal, (28) a common terminal (28a) is the noise reduction circuit
The first terminal (28b) is connected to the input terminal (22c) of (22), the first terminal (28b) is connected to the input terminal of the output circuit (24) , and the second terminal (28c) is connected to the output terminal of the first reproduction amplifier (19). A first selector switch whose 3 terminal (28d) is connected to the output terminal of the second reproduction amplifier (21) and whose 4th terminal (28e) is connected to the ground, and (29) is a common terminal (29a)
Is the input terminal of the recording amplifier (27), the first terminal (29b) is the output terminal of the first reproduction amplifier (19), and the second terminal (29c)
The second changeover switch but connected to the first output terminal of the noise reduction circuit (22) (22a), (30) is the first change-over switch from the first and second output terminal (31) and (32) ( a control signal for switching the 28), the control signal generating circuit for generating a control signal for switching the second changeover switch (29) from the third output terminal (33), (34) said control signal generating circuit ( A switch switching circuit for switching the first changeover switch (28) according to a control signal generated from the first and second output terminals (31) and (32) of (30), and (35) is a recording of the second deck. The recording / reproducing switch is switched from the P (playback) side to the R (recording) side by an operation.

The noise reduction circuit (22) is activated / deactivated according to the on / off state of the noise reduction switch (not shown) provided on the front panel of the tape recorder, and the second deck is in the recording state. The recording processing means is used when the first or second deck is in the reproduction state, and the reproduction processing means is used when the first or second deck is in the reproduction state according to the states of the first and second decks. A control signal is supplied to 36).

The control signal generation circuit (30) includes a first reproduction switch (37) closed in the reproduction state of the first deck, and a second reproduction switch (38) closed in the reproduction state of the second deck. , A recording switch (39) closed in the recording state of the second deck, and a first inverter (40) connected to the first reproduction switch (37)
And a first input terminal of which one input terminal is connected to the inverter (40)
A NOR circuit (41), a second inverter (42) connected to the second regeneration switch (38), and one input end of the inverter (42) connected to the first NOR circuit (41). A second NOR circuit (43) having the other input end connected to the output end and the output end connected to the other input end of the first NOR circuit (41);
A first AND circuit (44) having input terminals connected to the reproduction switch (37) and the recording switch (39), and a third inverter (45) connected to output terminals of the corresponding AND circuit (44).
And a second AND circuit (46) having one input terminal connected to the output terminal of the inverter (45) and the other input terminal connected to the recording switch (39), and the AND circuit (46). One input terminal is connected to the output terminal and the other input terminal is connected to the output terminal of the first NOR circuit (41); and the output terminal of the AND circuit (46). The second OR circuit (48) has one input terminal connected thereto and the other input terminal connected to the output terminal of the second NOR circuit (43).

In the control signal generating circuit (30) , the first reproduction switch (37), the second reproduction switch (38) and the recording switch (39) are all opened in the initial state where the first and second decks are not operated at all. Since it is in the state, the "L" signal is input to both the input terminals of the first inverter (40), the second inverter (42), the first AND circuit (44), and one input terminal of the second AND circuit (46). Is applied. Therefore, since the "H" signal is applied to one input terminal of both the first and second NOR circuits (41) and (43), the first and second NOR circuits (41) and (43) Both generate an "L" signal. Meanwhile, the first and second AND circuits (44)
And (46) both generate an "L" signal. Therefore, since the "L" signal is applied to both input terminals of both the first and second OR circuits (47) and (48), the first and second OR circuits (47) and (48) are applied. Both generate an "L" signal. That is, in the initial state, the "L" signals are all generated from the first to third output terminals (31) to (33) of the control signal generating circuit (30) . From this state, when the first deck is set to the reproduction state and the first reproduction switch (37) is closed, the “H” signal is applied to the first inverter (40) and the first NOR circuit (41) Since the "L" signal is applied to both input terminals, the "H" signal is generated from the first NOR circuit (41) and the "H" signal is output from the first output terminal (31). Will be generated. Further, since the "H" signal is applied to both input terminals of the second NOR circuit (43), the second NOR circuit (4)
An "L" signal is generated from 3). On the other hand, in the first AND circuit (44), the "L" signal is applied to the other input end, but the "L" signal is applied to the other input end.
Generate a signal. Therefore, the "L" signal is generated from both the second and third output terminals (32) and (33).

Next, when only the second deck is in the reproduction state and the second reproduction switch (38) is closed, this time, in contrast to the case where only the first deck is in the reproduction state, the first NOR circuit ( The "L" signal is generated from the 41), the "H" signal is generated from the second NOR circuit (43), and the "L" signal is generated from the first AND circuit (44). An "H" signal is generated from the output terminal (32), and an "L" signal is generated from the first and third output terminals (31) and (33).

In addition, when both the first and second decks are in the reproduction state and the first and second reproduction switches (37) and (38) are closed, the first and second decks are set in the reproduction state according to the first reproduction switch. Signals are generated from the first and second output terminals (31) and (32). That is, the first and second NOR circuits (4, 4) corresponding to the first closed switch of the first and second regeneration switches (37) and (38).
Since the "H" signal is generated from one of (1) and (43), the "H" signal is applied to the other one input terminal of the first and second NOR circuits (41) and (43). As a result, the switches that are closed later are connected to the first and second NOR circuits (41) and (4).
3) is not affected.

When the second deck is in the recording state and the recording switch (39) is closed, the first AND circuit (44) has the "L" signal at one input end and the "H" signal at the other input end. Since the signal is applied, the "L" signal is generated from the first AND circuit (44). Therefore, the "H" signal is applied to both input terminals of the second AND circuit (46), and the second AND circuit (46) is "H".
Generate a signal. Therefore, the first and second output terminals (3
An "H" signal is generated from both 1) and (32), and an "L" signal is generated from the third output terminal (33).

Next, in the state where the second deck is in the recording state, in the dubbing state where the first deck is in the reproducing state,
Since the recording switch (39) and the first reproduction switch (37) are closed, the "H" signal is applied to both input terminals of the first AND circuit (44), and the first AND circuit (44) outputs the signal. An "H" signal is generated. Therefore, the "L" signal is applied to one input terminal of the second AND circuit (46), and the "L" signal is generated from the second AND circuit (46). On the other hand, the "H" signal is generated from the first NOR circuit (41) as in the case where the first deck is brought into the reproducing state due to the closing of the first reproducing switch (37). Therefore, the first and third output terminals (31) and (33)
Produces an "H" signal and the second output terminal (32) produces an "L" signal.

That is, the states of the first and second decks described above, the open / closed states of the first reproduction switch (37), the second reproduction switch (38) and the recording switch (39) of the control signal generation circuit (30) , and the first Through 3rd output terminals (31) through (33) are summarized as shown in FIG.

The switch switching circuit (34) is the first of the control signal generating circuit (30).
When the control signals generated from the second output terminals (31) and (32) are both "H" signals, the common terminal (28a) of the first changeover switch (28) is the first terminal (28b), respectively. In the case of “H” and “L” signals, the common terminal (28a) is the second terminal (2
8c), the common terminal (28a) is the third terminal (28d) in the case of "L" and "H" signals respectively, and the common terminal (28a) is the fourth terminal (28a) in the case of both "L" signals. The first selector switch (28) is switched so that it is connected to ( 28e).

The second changeover switch (29) is the third switch of the control signal generating circuit (30) .
The common terminal (29a) is connected to the first terminal (29b) when the control signal generated from the output terminal (33) is the "H" signal.

In the apparatus described above, when performing reproduction of the magnetic tape in the first deck, the common terminal (23 function switch (23)
The reproduction operation of the first deck is performed by setting e) to the tape position connected to the first terminal (23a). Then, the first magnetic head (1
Playback of the magnetic tape is started in 8). Here, "H" and "L" signals are generated from the first and second output terminals (31) and (32) of the control signal generation circuit (30) , respectively, and from the third output terminal (33). Since the "L" signal is generated, it is connected to the common terminal (28a) and the second terminal (28c) of the first changeover switch (28) , and the common terminal (29a) of the second changeover switch (29 ) is the second terminal. Connected to (29c). Therefore, the reproduction signal reproduced by the first magnetic head (18) is not reproduced by the first reproduction amplifier (1
9), the first changeover switch (28) , the reproduction processing means of the noise reduction circuit (22), and the function switch (23) are supplied to the output circuit (24) . Therefore, the sound corresponding to the reproduction signal is radiated from the speaker 26, and the reproduction of the first deck is achieved. In this case, since the reproduction signal passes through the reproduction processing means of the noise reduction circuit (22),
If the magnetic tape played on the deck has been subjected to recording processing for noise reduction, turn on the noise reduction switch to activate the above-mentioned playback processing means and perform playback processing for noise reduction. If the magnetic tape has not been subjected to a recording process for noise reduction, the noise reduction switch is turned off and the reproduction processing means is not operated to use it as a mere linear amplifier. In some cases, it can be played correctly.

Also, when playing on the second deck, the common terminal (23e) of the function switch (23) is set to the tape position where the common terminal (23e) is connected to the first terminal (23a) as in the case of playing the first deck. Perform the playback operation of. Here, from the first and second output terminals (31) and (32) of the control signal generation circuit (30) ,
Since the "L" and "H" signals are generated and the "L" signal is generated from the third output terminal (33), the common terminal (28a) of the first changeover switch (28 ) is the third terminal ( 28d) and the common terminal (29a) of the second selector switch (29 ) is the second terminal.
Connected to terminal (29c). The recording / reproducing switch (35) is located on the P (playback) side. Therefore, the second magnetic head
The magnetic tape is reproduced at (20), the reproduction signal is passed through the second reproduction amplifier (21) and the first changeover switch (28) , and then the output circuit ( 24) and the reproduction on the second deck is achieved. Also in this case, as in the case of the reproduction of the first deck, by turning on / off the noise reduction switch according to the magnetic tape to be used, the magnetic tape subjected to the recording processing for the noise reduction and the applied magnetic tape. Not both magnetic tape can be played correctly.

Next, when recording a magnetic tape on the second deck, switch the function switch (23) according to the source signal to be recorded, and set the common terminal (23e) to the first to fourth terminals (23a).
To (23d). When recording a source signal other than the reproduction signal of the first deck, set the function switch (23) to the second terminal (23b) and the third terminal (23).
c) Or switch to the 4th terminal (23d) and perform the recording operation of the 2nd deck. Then, "H" signal is generated from both the first and second output terminals (31) and (32) of the control signal generating circuit (30) , and "L" signal is generated from the third output terminal (33). Therefore, the common terminal (28a) of the first changeover switch (28) is connected to the first terminal (28b), and the common terminal (29a) of the second changeover switch (29) is connected to the second terminal (29c). To be done. The recording / reproducing switch (35) is switched to the R (recording) side. Therefore, the source signal selected by the function switch (23) is supplied to the output circuit (24) and also to the noise reduction circuit (22) via the first changeover switch (28) . The source signal supplied to the output circuit (24) is the speaker (26).
The noise reduction circuit (2
The source signal supplied to 2) is output from the first output terminal (22a) via the recording processing means of the noise reduction circuit (22), and the recording amplifier (27) via the second changeover switch (29 ). Is supplied to the second magnetic head (20) as a recording signal by superposing a bias current in the recording amplifier (27). Therefore, recording is performed on the magnetic tape loaded in the second deck. In this case, since the source signal recorded by the second deck passes through the recording processing means of the noise reduction circuit (22), turning on the noise reduction switch activates the recording processing means, If the magnetic tape used for the second deck is recorded with a recording signal that has been subjected to a recording process for noise reduction, and the noise reduction switch is turned off,
When the recording processing means is in a non-operating state, it becomes a mere linear amplifier, and a recording signal which is not subjected to recording processing for noise reduction is recorded on the magnetic tape.

When recording the reproduction signal of the first deck on the second deck, that is, during dubbing, the function switch (23) is switched to the first terminal (23a) to perform the recording operation on the second deck. Perform the deck playback operation. Then,
The first and second output terminals (31) of the control signal generation circuit (30 ) and
From (32), "H" and "L" signals are generated,
Since the "H" signal is generated from the third output terminal (33),
The common terminal (28a) of the first selector switch (28 ) is the second terminal (2
8c) and is connected to the common terminal (29 ) of the second selector switch (29).
a) is connected to the first terminal (29b). The recording / reproducing switch (35) is switched to the R side. Therefore, the first magnetic head (18)
The reproduction signal reproduced by is supplied to the output circuit (24) through the first reproduction amplifier (19), the first changeover switch (28) , the reproduction processing means of the noise reduction circuit (22) and the function switch (23). The sound is emitted by the speaker (26) and monitored. Further, at this time, since the reproduction signal of the first deck via the first reproduction amplifier (19) is supplied to the recording amplifier (27) via the second changeover switch (29) , the reproduction signal is recorded by the recording amplifier (27). The bias current is superposed by the amplifier (27) and is supplied to the second magnetic head (20) as a recording signal. Therefore, the reproduction signal of the first deck is recorded on the magnetic tape loaded in the second deck, and the dubbing recording is achieved. Then, in this case, since the reproduction signal of the first deck is supplied to the output circuit (24) through the reproduction processing means of the noise reduction circuit (22),
If the magnetic tape reproduced on the first deck has been subjected to recording processing for noise reduction, a noise reduction switch is turned on to activate the reproduction processing means, and reproduction processing for noise reduction is performed. If the magnetic tape has not been subjected to recording processing for noise reduction, the noise reduction switch is turned off and the playback processing means is not operated, and the magnetic tape is used as a simple linear amplifier. You can monitor correctly in both cases. In addition, since the reproduction signal of the first deck is directly supplied to the recording amplifier (27) after passing through the first reproduction amplifier (19), the magnetic tape reproduced by the first deck is recorded for noise reduction. If it has been processed, it is recorded as it is on the magnetic tape loaded in the second deck as it is.
If the magnetic tape reproduced on the deck is not subjected to the recording processing for noise reduction, the magnetic tape loaded on the second deck is recorded as it is without the recording processing.

In the above dubbing, the function switch (23) was set to the tape position, and dubbing was performed while monitoring the playback signal of the first deck, but the playback signal of the record player or CD player and the received signal of the tuner were You can also dubb while listening.

Further, when at least one of the first and second decks has an automatic music selection function capable of locating a desired music from a plurality of music recorded on a magnetic tape, an automatic music selection operation of the deck the first and second regeneration switch in the medium, the control signal generating circuit (30) (37) and (38) if as is remains open, the control signal generating circuit during automatic music selection operation (30) Since the "L" signal is generated from both the first and second output terminals (31) and (32) of the above, the common terminal (28a) of the first changeover switch (28 ) is connected to the fourth terminal (28e). It Therefore, it is possible to mute the annoying reproduction signal during the automatic music selection operation reproduced by the first or second magnetic head (18) or (20).

(G) Effects of the Invention As described above, according to the present invention, the switching states of the first changeover switch and the second changeover switch are controlled according to the operating states of the first and second decks, and the first or second changeover switch is controlled. When the second deck is played back, the first selector switch is controlled to supply the tape playback signal to the noise reduction circuit, and the input signal of the output circuit is fed to the noise reduction circuit when the second deck is not playing. The first changeover switch is controlled to be supplied, and the second changeover switch is changed to supply the signal passing through the noise reduction circuit to the recording circuit of the second deck. The tape reproduction signal is directly supplied to the noise reducing circuit, and the tape reproduction signal is directly supplied to the recording circuit of the second deck. Since the control to switch the second changeover switch is performed to supply the tape, the tape reproduction signal which is subjected to the recording process for the noise reduction not only during the reproduction of the first and second decks but also during the dubbing is properly monitored. It is possible to record the source signal other than the tape playback signal by the noise reduction circuit at the time of recording by the second deck, and it is recorded again on the tape playback signal that has been recorded at the time of dubbing. It is possible to prevent the processing from being performed and to correctly monitor the tape reproduction signal on which the recording processing is performed.

In particular, the signal paths used according to the operating states of the first and second decks are automatically selected, and the signal passing through the noise reduction circuit is automatically selected. There is no need to consider the signal path when properly monitoring the tape playback signal, which simplifies the operation and ensures that the tape playback signal that has already been recorded will not be recorded again. .

[Brief description of drawings]

FIG. 1 is a circuit diagram showing an embodiment of the present invention, FIG. 2 is a circuit diagram showing a conventional double-deck type tape recorder, and FIG. 3 is a first deck and a second deck of a control signal generating circuit, respectively. FIG. 6 is an explanatory diagram showing the relationship between the switch and the output signal. Description of main drawing numbers (18) ... First magnetic head, (19) ... First reproducing amplifier, (20) ...
Second magnetic head, (21) ... Second reproduction amplifier, (22) ... Noise reduction circuit, (24) Output circuit, (27) ... Recording amplifier, (28) ... First changeover switch, (29) ... Second Changeover switch, (30) ... Control signal generation circuit.

Claims (1)

[Claims] 1. A tape recorder comprising a first deck having a reproducing function and a second deck having a recording and reproducing function, wherein the recording and reproducing processing for respectively performing recording and reproducing processing for reducing noise of a magnetic tape. A noise reduction circuit having means, a function switch for selecting an output signal from the reproduction processing means of the noise reduction circuit and a source signal other than the tape reproduction signal by the first and second decks, and the function switch. An output circuit for monitoring the selected source signal and an input signal of the output circuit when switched to the first position, and a reproduction signal of the first deck when switched to the second position, to the third position. A first selector switch for supplying the reproduction signal of the second deck to the noise reduction circuit when switched, and a selector switch for switching to the first position. The reproduction signal of the first deck when the,
A second changeover switch for supplying an output signal from the recording processing means of the noise reduction circuit to the recording amplifier of the second deck when switched to the second position, and a reproduction state during reproduction of the first or second deck. The first changeover switch is changed over to the second or third position in accordance with the deck formed in 1., and the first changeover switch is changed over to the first position when the second deck, which is not in the reproduction state, is recorded. And a control signal generation circuit for generating a control signal for controlling the second changeover switch to the second position and controlling the second changeover switch to the first position during dubbing. A tape recorder characterized by that.