JPH0525046Y2 - - Google Patents

Description

[Detailed description of the invention] <Industrial field of application> The invention is a double cassette tape recorder that can continuously play two cassette tapes. There is a trigger circuit that conducts to ground and emits a playback start signal for the other tape from its output terminal, and a noise reduction circuit (hereinafter referred to as NR).
circuit) is turned on (IN) and turned off (OUT).
switching circuit (hereinafter referred to as SC circuit)
This invention relates to a double cassette tape recorder equipped with the following.

<Conventional technology> In conventional general tape recorders of this type,
As shown in Figure 3, if the continuous playback switch CONT-SW connected to the trigger circuit T side is turned on, playback of one tape will start, but the SC
Noise reduction switch installed in the circuit
The NR-SW was a manual switch that did not switch automatically when one of the former tapes was started. A normal NR circuit has an input terminal for controlling NR-ON and OR-OFF, and when a high-level signal is applied to the terminal, no noise reduction operation is performed and a low-level signal is applied. If the noise is detected, the noise reduction operation is performed. It should be noted that the numbers of other components are used for the embodiments of the present invention to be described later.

<Problem that the invention aims to solve> Therefore, there are two types of tapes: tapes recorded with noise reduction (hereinafter referred to as NR-IN tapes) and tapes recorded without noise reduction (hereinafter referred to as NR-OUT tapes). (described as tape)
If these tapes are played back consecutively, appropriate playback characteristics can be obtained for one of the tapes, but a situation arises in which appropriate playback characteristics cannot be obtained for the other tape.

In other words, the noise reduction switch NR
When playing continuously with –SW turned on (IN), the NR
-When playing back an OFF tape, the treble range characteristics are significantly attenuated, and conversely, when playing continuously with the NR-SW set to OUT, when playing an NR-IN tape, the treble range response increases excessively, resulting in noticeable noise and playback. There is a problem with the sound quality.

Therefore, in order to always obtain appropriate playback characteristics with conventional tapes, NR-OUT tapes,
Each time the reproduction is switched between NR-IN tapes, it is necessary to manually switch the noise reduction switch NR-SW, which has the disadvantage that the effect of continuous reproduction is halved.

In view of these circumstances, the present invention provides a double cassette tape recorder that can always exhibit proper and good playback characteristics during continuous playback using a mixture of NR-IN and NR-OUT tapes. have a purpose.

<Means for solving the problems> To explain the structure of the means taken by the present invention in order to achieve the above object, with reference to FIGS. A trigger circuit T has an output terminal 2 that is electrically connected to ground in response to a playback end signal, and emits a playback start signal for the other tape from the output terminal 2, a switching circuit SC that turns on and off the noise reduction circuit NR, and a flip-flop. In a double cassette tape recorder equipped with a circuit F and a mode changeover switch SW for switching modes, the trigger circuit T has a terminal 1 for inputting a playback end signal of one tape, and the trigger circuit T has a terminal 1 for inputting a playback end signal of one tape, and It consists of a circuit in which a fifth transistor Q ₅ and a sixth transistor Q ₆ are connected in series, which is turned on instantaneously by an end signal, and an output terminal 2 of the series circuit, and the output terminal 2 has a The playback start signal output terminal 3 for the other tape is connected, and the switching circuit SC that turns on and off the noise reduction circuit NR is a noise reduction circuit.
A noise reduction switch NR- is equipped with a terminal 8 connected to NR, and is selectively connected to either a noise reduction-in mode in which the noise reduction circuit NR is turned on or a noise reduction-out mode in which it is turned off. Seventh transistor Q ₇ for output with SW connected to grounded emitter
Connect to the base of the CONT-
The flip-flop circuit F has an input terminal 7 connected to an ON/OFF switching piece of the SW, and an indicator ID.
a transistor Q ₁ for output, a fourth transistor Q ₄ for output, a second transistor Q 2 for input, a _{third transistor Q 3 for} input, and a transistor for input whose resistance value is set to R ₁ < R ₂ . A first resistor R ₁ and a second input resistor R ₂ are connected in a symmetrical trigger type flip-flop, and the base of the third input transistor Q ₃ is connected to the control input terminal 4. The changeover switch SW is a first changeover piece S connected to the output terminal 2 of the trigger circuit T.
1, and a second switching piece S2 connected to the ON switching piece ON of the continuous playback switch CONT-SW and interlocking with the first switching piece S1, and both switching pieces S1 and S2 are 1
Noise reduction mode - Out NR
-OUT to noise reduction -in NR-IN
The second mode is off mode, and the third mode is noise reduction.
Noise reduction from IN NR-IN to OUT
It has two interlocking circuits and three contacts that switch the position to three types of modes, including a mode that switches to NR-OUT, and the first contact S1 of the first switching piece S1
, a third contact S1 to the control input terminal 4 of the flip-flop circuit F, and a first contact S2 of the second switching piece S2 to the collector of the fourth output transistor _Q4 ; This is a double cassette recorder, in which the contacts S2 of the two transistors are connected to the collectors of the first output transistors _Q1 .

<Function> According to the double cassette tape recorder of the present invention having such a characteristic configuration, the NR-IN
When playing back a tape and an NR-OUT tape mixedly, the above steps are performed according to the playback order of both tapes.
By presetting the switching direction of the SC circuit, the signal generated from the output terminal 2 of the trigger circuit T at the time of switching from the preceding playback tape to the subsequent playback tape is used to operate the flip-flop circuit F, and the SC circuit can be automatically switched in a direction that suits the recording characteristics of each tape.

<Examples> Examples of the present invention will be described below in detail based on the drawings.

In Fig. 1, T is a trigger circuit built into the recorder main body, and is connected to a terminal 1 that inputs a playback end signal obtained from the play operation when playback of one tape ends, and an input from the terminal 1. a circuit in which a fifth transistor Q ₅ and a sixth transistor Q ₆ are connected in series, which is instantaneously turned on by the termination signal; transistor
Due to the ON operation of _Q5 and the sixth transistor _Q6 ,
An output terminal 2 o'clock is provided with a ground potential, and a reproduction start signal output terminal 3 for the other tape is connected to the output terminal 2.

SC enters the noise reduction circuit NR (IN)
It is a switching circuit that turns off (OUT),
A noise reduction switch that includes a terminal 8 connected to the noise reduction circuit NR and selectively connects the noise reduction circuit NR to either a noise reduction-in mode or a noise reduction-out mode in which it is turned off. NR−
Connect SW to the base of the seventh transistor _Q7 whose emitter is connected to ground, and set up the continuous regeneration switch.
Input terminal 7 connected to CONT-SW switching piece
and indicator ID.

F is a first transistor for output Q ₁ , a fourth transistor for output Q ₄ , a second transistor for input Q ₂ , and a third transistor for input Q ₃
and a first resistor R ₁ for input and a second resistor R ₂ for input, each with a resistance value set to R ₁ < R ₂
The base of the third input transistor _Q3 is connected via the control input terminal 4 to the first switching contact S1 and the third switching contact S1 of the mode switching switch SW. When the power supply +B is applied, the third input transistor _Q3 is turned on and the fourth input transistor _Q4 is initialized off.

SW is a mode change switch, and is a switching piece S1 connected to the output terminal 2 of the trigger circuit T.
and a second switching piece S2 connected to the on switching piece ON of the continuous playback switch CONT-SW and interlocking with the switching piece S1, both switching pieces S1 and S2 having two interlocking circuits and three contacts for switching positions among three modes: a first mode for switching from noise reduction-out NR-OUT to noise reduction-in NR-IN, a second mode for switching from noise reduction-in NR-IN to noise reduction-out NR-OUT,
a first contact S1 of the first switching piece S1;
The third contact S1 is connected to the flip-flop circuit F
a first contact S2 of the second switching piece S2 connected to the collector of the fourth output transistor _Q4 , and a third contact S2 of the second switching piece S2 connected to the collector of the first output transistor _Q1 .

Next, the operation of the present invention will be briefly explained. For example, set an NR-OUT tape in one leading tape deck and an NR-IN tape in the other succeeding tape deck, and then turn on the continuous playback switch.
If you want to turn on the CONT-SW and want to play back both tapes continuously in the order listed, preset the mode changeover switch SW to the first mode ( ) and switch the switching circuit SC.
OUT the noise reduction switch NR-SW.
Switch to the position and turn on the power +B. In this case, the third transistor _Q3 of the flip-flop circuit F is turned on and the fourth transistor _Q4 is turned off, so that the switching circuit SC
Transistor Q ₇ remains off, its collector is held at high level, and the NR circuit at terminal 8 remains in off mode, allowing the NR-OUT tape to be played back in accordance with its recording characteristics. .

When the NR-OUT tape reaches the tape end and its playback ends, the end signal enters the input terminal 1 of the trigger circuit T, and the fifth and sixth transistors Q ₅ and Q ₆ are turned on momentarily. Therefore, the output terminal 2 becomes the ground potential, and the ground potential is applied to the input terminal 8 of the other tape deck and the control input terminal 4 of the flip-flop circuit F, respectively. As a result, the other tape deck with the NR-IN tape set is activated, and the third transistor _Q3 in the flip-flop circuit F is turned off and the fourth transistor _Q4 is turned on.
The seventh transistor _Q7 of the switching circuit SC remains off, but its collector goes low, and terminal 8 automatically switches to the mode of the NR circuit on, and the NR-IN tape adapts to its recording characteristics. This led to the regeneration that took place.

Also, if you want to set an NR-IN tape in one tape deck and an NR-OUT tape in the other tape deck and play them continuously in the same way as described above, preset the mode changeover switch SW to the third mode (). and turn on power +B. At this time, the second transistor _Q2 of the flip-flop circuit F is turned off, the first transistor _Q1 is turned on, the seventh transistor _Q7 of the switching circuit SC remains off, its collector becomes low level, and the terminal 8 is turned off. becomes NR circuit on mode. When the NR-IN tape reaches the tape end, the flip-flop circuit F's second
transistor Q ₂ is on, the third transistor
Q ₃ and the first transistor Q ₁ are both turned off,
The collector of the seventh transistor _Q7 of the switching circuit SC becomes high level, and the terminal 8 becomes NR.
This leads to the circuit switching to off mode.

Figures 2A and 2B are schematic block diagrams of the two operating models described above, where AMP is an amplifier;
SP is a speaker, A indicates continuous playback of switching from NR-OUT tape to NR-IN tape, and B indicates continuous playback of switching from NR-IN tape to NR-OUT tape.

<Effects of the invention> As can be understood from the detailed description above, the present invention has the following advantages: (1) When NR-IN tape and NR-OUT tape are mixed and both tapes are played back consecutively. ,
The IN-OUT switching operation for the reproduction circuit of the NR circuit can be automated, eliminating the hassle of manual switching operations during continuous reproduction.

(2) Since the switching is automatic, it is possible to reliably obtain appropriate and good playback sound quality that matches the recording characteristics of each tape.

[Brief explanation of drawings]

Figure 1 is a circuit diagram of the main parts of an embodiment of the present invention, Figure 2
Figures A and B are schematic block diagrams of operations in two continuous playback modes, and Figure 3 is a circuit diagram of a conventional main part. 1 is the input terminal of the trigger circuit, 2 is the output terminal of the trigger circuit, 3 is the playback start signal output terminal for the other tape, 4 is the control signal input terminal, 8 is the terminal of the switching circuit SC, F is the flip-flop circuit, and T is the flip-flop circuit. Trigger circuit, Q ₁ is the first transistor, Q ₂ is the second transistor, Q _{3 is the third transistor, Q 4 is} the fourth transistor, Q ₅ is the fifth transistor, Q ₆ is the sixth transistor ,
Q ₇ is the seventh transistor, R ₁ is the first resistor, R ₂
is the second resistor, S1 is the first switching piece, S2 is the second switching piece, S1 is the first switching piece S1
, S1 is the second contact of the first switching piece S1, S1 is the third contact of the first switching piece S1, and S2 is the first contact of the second switching piece S2.
, S2 is the second contact of the second switching piece S2, S2 is the third contact of the second switching piece S2, NR is the noise reduction circuit, SC is the switching circuit, SW is the mode switching switch,
NR-SW is a noise reduction circuit switch,
NR-IN is noise reduction-in (mode),
NR-OUT is the noise reduction out (mode), CONT-SW is the continuous playback switch, ON is the ON switch of the continuous playback switch, and OFF is the OFF switch of the continuous playback switch.

Claims (1)

[Claims for Utility Model Registration] A trigger circuit T having an output terminal 2 which is electrically connected to ground in response to a reproduction end signal of one tape, and which emits a reproduction start signal for the other tape from the output terminal 2, and a noise reduction circuit. In a double cassette tape recorder equipped with a switching circuit SC that turns on and off the circuit NR, a flip-flop circuit F, and a mode changeover switch SW that changes the mode, the trigger circuit T is a terminal that inputs a playback end signal of one tape. 1, and a circuit in which a fifth transistor Q ₅ and a sixth transistor Q ₆ are connected in series, which is instantaneously turned on by the termination signal inputted from the terminal 1, and an output of the series circuit. The output terminal 2 is connected to a playback start signal output terminal 3 for the other tape, and the switching circuit SC for turning on and off the noise reduction circuit NR is a noise reduction circuit.
A noise reduction switch NR- is equipped with a terminal 8 connected to NR, and is selectively connected to either a noise reduction-in mode in which the noise reduction circuit NR is turned on or a noise reduction-out mode in which it is turned off. Seventh transistor Q ₇ for output with SW connected to grounded emitter
Connect to the base of the CONT-
The flip-flop circuit F has an input terminal 7 connected to an ON/OFF switching piece of the SW, and an indicator ID.
transistor Q ₁ for output, a fourth transistor Q ₄ for output, a second transistor Q ₂ for input, a third transistor Q ₃ for input, and a transistor for input whose resistance value is set to R ₁ < R ₂ . A first resistor R ₁ and a second resistor R ₂ for input are connected in a symmetrical trigger type flip-flop, and the base of the third transistor Q ₃ for input is connected to the control input terminal 4. The changeover switch SW is a first changeover piece S connected to the output terminal 2 of the trigger circuit T.
1, and a second switching piece S2 connected to the ON switching piece ON of the continuous playback switch CONT-SW and interlocking with the first switching piece S1, and both switching pieces S1 and S2 are connected to the ON switching piece ON of the continuous playback switch CONT-SW, and the switching pieces S1 and S2 are 1
Noise reduction mode - Out NR
-OUT to noise reduction -in NR-IN
The second mode is off mode, and the third mode is noise reduction.
Noise reduction from IN NR-IN to OUT
It has two interlocking circuits and three contacts that switch the position to three types of modes, including a mode that switches to NR-OUT, and the first contact S1 of the first switching piece S1
, a third contact S1 to the control input terminal 4 of the flip-flop circuit F, and a first contact S2 of the second switching piece S2 to the collector of the fourth output transistor _Q4 . A double cassette recorder, in which the contacts S2 of the transistors Q1 _{and 2} are respectively connected to the collectors of the first output transistors Q1.