JPH0411235Y2 - - Google Patents

Description

[Detailed explanation of the invention] (a) Industrial application field The present invention relates to a tape recorder, especially the first one.
The present invention relates to a display circuit for a tape recorder with a reciprocating playback function, which has a playback function in one direction and a playback function in a second direction opposite to the first direction. (b) Prior Art Recently, a cassette tape recorder called a head-on stereo, which uses a head-on to listen to the reproduction signal of a magnetic tape, has become popular. In such a cassette tape recorder,
Since long playback is required, many devices are equipped with a reciprocating playback function that allows playback on both sides without removing the cassette. A tape recorder having such a reciprocating playback function generally has a first magnetic head that plays back signals recorded on a track in a first direction of the magnetic tape, and a signal recorded on a track in a second direction of the magnetic tape. It is provided with a second magnetic head for reproducing signals, and is configured to be switched between the first magnetic head and the second magnetic head in accordance with the reproducing direction. As a technique for switching between the first magnetic head and the second magnetic head in accordance with the reproduction direction, for example, Japanese Utility Model Publication No. 57-5687
There is something disclosed in the publication No. A tape recorder with a reciprocating playback function is a device that automatically switches the playback direction when the magnetic tape reaches the end after playing in the first direction and starts playing in the second direction. That is, it is equipped with an automatic reversing device. A technique for performing such automatic reversal is disclosed, for example, in Japanese Patent Publication No. 51-48044. A tape recorder equipped with such a reciprocating playback function is equipped with an automatic reversing device that detects the end of the magnetic tape and reverses the playback direction, as well as a reversal device that manually switches the playback direction midway through the magnetic tape. Such a technique is disclosed, for example, in Japanese Patent Application Laid-Open No. 71152/1983. Further, a tape recorder having such a reciprocating playback function is equipped with means for displaying in which direction the playback operation is being performed,
A technique for electrically displaying the reproduction direction is disclosed in Japanese Utility Model Application Publication No. 56-93892. (c) Problems to be solved by the invention In a tape recorder with a reciprocating playback function that is equipped with the above-mentioned manual playback direction reversal device, for example, it is possible to switch the playback direction during playback operation in the first direction. When a playback operation is performed in the second direction, the song recorded on the track in the second direction is often played back from the middle. Therefore, such tape recorders require repeated rewinding and playback operations in order to find the beginning of a song, which is very inconvenient. This idea is
The present invention aims to provide a display circuit that is improved in this respect. (d) Means for Solving the Problems The present invention, when a playback operation in the first direction is being performed, replaces the non-signal portion between the signals recorded on the track in the second direction with the second direction. When a playback operation is being performed in the first direction, a no-signal portion detection circuit is provided to detect a no-signal portion between the signals recorded on the track in the first direction, and the detection signal of the no-signal portion detection circuit is A blinking drive circuit that becomes active when the voltage is applied is provided, and the light emitting diode is caused to blink by the blinking drive circuit. (e) Effect This invention provides a tape recorder with a reciprocating playback function, which is provided in correspondence with a track in the other direction when a signal recorded on a track in one direction is being played back and listened to; A light emitting diode which is provided to detect a no-signal portion between signals recorded on a track which is not being reproduced by using a magnetic head which is not in use and to indicate the direction of reproduction, and which is also not in use. The fact that a no-signal area has been detected is displayed by blinking the display. (F) Embodiment The illustrated circuit is an embodiment of the control circuit of the present invention. In the figure, 1 and 2 are first and second magnetic heads that respectively reproduce left and right channel signals recorded on tracks in the first direction of the magnetic tape, and 3 and 4 are in the second direction of the magnetic tape. third and fourth magnetic heads for respectively reproducing left and right channel signals recorded on the tracks;
5, 6, 7, and 8 are first, second, third, and fourth switching switches that are switched by a magnetic tape playback direction switching device, and are connected to first terminals 5a, 6, respectively.
a, 7a, 8a, second terminal 5b, 6b, 7b, 8
b and movable terminals 5c, 6c, 7c, and 8c. The first terminal 5a of the first changeover switch 5 is connected to the signal terminal of the first magnetic head 1, and the second terminal 5b is connected to the signal terminal of the third magnetic head 3. The first terminal 6a of the second changeover switch 6 is connected to the signal terminal of the second magnetic head 2, and the second terminal 6b is connected to the signal terminal of the fourth magnetic head 4. Said third changeover switch 7
The first terminal 7a is connected to the signal terminal of the third magnetic head 3, and the second terminal 7b is connected to the signal terminal of the first magnetic head 1. Further, the first terminal 8a of the fourth changeover switch 8 is connected to the signal terminal of the fourth magnetic head 4, and the second terminal 8b is connected to the signal terminal of the second magnetic head 2. 9 is a first preamplifier circuit for amplifying the reproduced signal from the first magnetic head 1 or the third magnetic head 3 that is input through the first changeover switch 5; a first variable resistor to which an amplified reproduction signal is applied and which adjusts the level of the signal;
Reference numeral 1 denotes a first main amplifier circuit to which a signal whose level has been adjusted by the first variable resistor 10 is input and which amplifies the signal. 12 is a second preamplifier circuit for amplifying the reproduced signal from the second magnetic head 2 or the fourth magnetic head 4 that is input through the second changeover switch 6; A second variable resistor 14 receives the signal whose level has been adjusted by the second variable resistor 13 and amplifies the signal. This is the second main amplifier circuit. 15 is a headphone jack into which a headphone plug is inserted;
A first signal terminal 16 to which the signal amplified by the main amplifier circuit 11 is applied, and the second main amplifier circuit 14
It has a second signal terminal 17 to which a signal amplified by is applied, and a ground terminal 18 that is grounded. Reference numeral 19 receives signals reproduced by the first magnetic head 1, second magnetic head 2, third magnetic head 3, and fourth magnetic head 4 through the third changeover switch 7 and fourth changeover switch 8. This is a no-signal portion detection circuit that detects a no-signal portion between signals, and includes an output terminal 20 that outputs a detection signal when a no-signal portion formed between signals is detected. Reference numeral 21 denotes a blinking drive circuit which becomes active when a detection signal is output to the output terminal 20 of the no-signal portion detection circuit 19, and when in the operating state, outputs an H (high) level signal and a L level signal to its output terminal 22. (low)
It is configured to alternately output level signals. 23 is a fifth changeover switch that is switched in conjunction with the changeover switches 5, 6, 7, and 8, and has a first terminal 23a, a second terminal 23b, and a resistor 2.
A movable terminal 23c connected to the power supply via 4
It is equipped with 25 is the changeover switch 5, 6,
7 and 8, and includes a first terminal 25a, a second terminal 25b, and a movable terminal 25c connected to the output terminal 22 of the blinking drive circuit 21. 26, the anode is connected to the first terminal 23 of the fifth changeover switch 23;
a and the second terminal 25b of the sixth changeover switch 25, and its cathode is grounded.
This serves to indicate that a playback operation in the direction is being performed. 27 has an anode connected to the second terminal 23b of the fifth changeover switch 23 and the sixth terminal 27.
A second light emitting diode which is connected to the first terminal 25a of the changeover switch 25 and whose cathode is grounded, and whose lighting serves to indicate that a regeneration operation in the second direction is being performed. It is. In such a configuration, the first changeover switch 5, the second changeover switch 6, the third changeover switch 7, the fourth changeover switch 8, the fifth changeover switch 23, and the sixth changeover switch 25 are used to switch the reproduction direction of the magnetic tape. It is connected so that it can be switched to the opposite side in conjunction with. The display circuit of the present invention is constructed as described above, and its operation will be explained next. The illustrated state of the switch is a state in which the regeneration operation is performed in the first direction, and when the regeneration operation is performed in this state, power is supplied to each circuit and the drive mechanism is in the first direction.
The tape recorder enters a state in which a playback operation is performed in the first direction. The left channel signal reproduced by the first magnetic head 1 is input to the first preamplifier circuit 9 through the first changeover switch 5, amplified, and then applied to the first variable resistor 10. The reproduced signal from the first magnetic head 1 applied to the first variable resistor 10 is input to the first main amplifier circuit 11 after its level is adjusted and is amplified .
The signal is output to the first signal terminal 16 of No. 5. The right channel signal reproduced by the second magnetic head 2 is input to the second preamplifier circuit 12 through the second changeover switch 6, amplified, and then applied to the second variable resistor 13. The reproduced signal from the second magnetic head 2 applied to the second variable resistor 13 is input to the second main amplifier circuit 14 after its level is adjusted and is amplified .
is output to the second signal terminal 17 of. Therefore, in such a state, if the headphone plug is inserted into the headphone jack 15 , the headphone will record the signal reproduced by the first magnetic head 1 and the second magnetic head 2, that is, the track in the first direction. You can listen to the left and right channel signals in stereo. In this way the first
In this state, a drive current flows to the first light emitting diode 26 through the fifth changeover switch 23, so that the first light emitting diode 26 is lit. Therefore, the user can recognize that the tape recorder is playing in the first direction by the lighting of the first light emitting diode 26. While the playback operation in the first direction is being performed, the signals of the left and right channels recorded on the track in the second direction are played back by the third magnetic head 3 and the fourth magnetic head 4. Third changeover switch 7
and is inputted to the no-signal portion detection circuit 19 through the fourth changeover switch 8. Third magnetic head 3 and fourth magnetic head
When there is a signal reproduced by the magnetic head 4, no detection signal is output to the output terminal 20 of the no-signal portion detection circuit 19, so the blinking drive circuit 21 is in a non-operating state. Therefore, the second light emitting diode 27 is not driven to blink and is in a non-lighting state. The playback operation in the first direction is performed in this state, but when a no-signal part between the signals recorded on the track in the second direction is detected, the output terminal of the no-signal part detection circuit 19 is A detection signal is output to 20. When a detection signal is output to the output terminal 20 of the no-signal detection circuit 19, the blinking drive circuit 21 to which the signal is applied becomes operational, and the output terminal 22
An H level signal and an L level signal are output. As a result, the H level signal and L level signal which are the output signals of the blinking drive circuit 21 are applied to the second light emitting diode 27 through the sixth changeover switch 25, so that the second light emitting diode 27 is driven to blink. become. Therefore, by blinking the second light emitting diode 27, the user can detect that the non-signal area between the signals recorded on the track in the second direction is in the third direction.
It can be recognized that the data is being reproduced by the magnetic head 3 and the fourth magnetic head 4. When the user manually switches the playback direction while the second light emitting diode 27 is blinking, the magnetic tape drive mechanism is switched to playback in the second direction, and the first changeover switch is switched on. 5, second changeover switch 6, third changeover switch 7, fourth changeover switch 8, fifth changeover switch 23
And the sixth changeover switch 25 is switched to the opposite side from the illustrated state. When such a switching operation is performed, the left channel signal reproduced by the third magnetic head 3 is input to the first preamplifier circuit 9 through the first changeover switch 5, and is reproduced by the fourth magnetic head 4. The right channel signal thus obtained is input to the second preamplifier circuit 12 through the second changeover switch 6. The reproduced signal from the third magnetic head 3 amplified by the first preamplifier circuit 9 is further amplified by the first main amplifier circuit 11 and then sent to the first signal terminal 16 of the headphone jack 15. Output.
Further, the reproduced signal from the fourth magnetic head 4 amplified by the second preamplifier circuit 12 is further amplified by the second main amplifier circuit 14 and then sent to the second signal terminal 17 of the headphone jack 15. is output to.
Therefore, the user will now be able to playback and listen to the signal recorded on the track in the second direction instead of the playback signal in the first direction that has been played back and listening to it up until now, but such a playback operation The no-signal portion detection circuit 1
9, the user can listen to the beginning of the song recorded next to the no-signal portion. Regeneration operation in the second direction is performed in this state, but since the fifth changeover switch 23 is switched to the opposite side from the state shown in the figure, the regeneration operation is performed through the fifth changeover switch 23. A drive current flows through the second light emitting diode 27. Therefore, the second light emitting diode 27 is turned on, indicating that the reproducing operation in the second direction is being performed. Further, when the reproduction operation in the second direction is performed, the no-signal portion detection circuit 19 detects the first magnetic head 1 and the second magnetic head.
The signal recorded on the track in the first direction to be reproduced by the magnetic head 2 is inputted through the third changeover switch 7 and the fourth changeover switch 8. Therefore, in a state where the reproduction operation in the second direction is being performed, the no-signal portion detection circuit 1
9 is in a state of detecting a no-signal portion between the signals recorded on the track in the first direction, and the output of the blinking drive circuit 21 is applied to the first light emitting diode 26 through the sixth changeover switch 25. is in a state of Therefore, as described above, when the first light emitting diode 26 is blinking due to the detection of a no-signal portion between the signals recorded on the track in the first direction, the playback direction switching operation is performed. After the movement is performed, the song recorded on the track in the first direction can be played back and listened to from the beginning. In this way, the first light emitting diode 2
If the playback direction is switched when the light emitting diode 6 or the second light emitting diode 27 flashes, the song recorded on the track in the opposite direction can be played back and listened to from the beginning, but the light emitting diodes 26 and 27 flash. Even if the playback direction is not switched, the playback operation will continue as it is. When the signal recorded next to the no-signal section is played back, the output terminal 2 of the no-signal section detection circuit 19
Since the detection signal that was output to 0 disappears and the blinking drive circuit 21 becomes inactive, the first
Light emitting diode 26 or second light emitting diode 27
becomes unlit. In this embodiment, a stereo tape recorder has been described, but it is of course possible to implement the present invention in a monaural tape recorder. Although mechanical switches were used as the first changeover switch 5, second changeover switch 6, third changeover switch 7, fourth changeover switch 8, fifth changeover switch 23, and sixth changeover switch 25, switching elements such as transistors were used. It can also be used and configured. Further, although the signal reproduced by the magnetic head is listened to by a headphone, it can also be listened to by a speaker. (g) Effect of the invention The display circuit of the invention detects the no-signal portion between the signals recorded on the tracks in the other direction when the signals recorded on the tracks in one direction are played back and listened to. Since it is detected and displayed,
If you switch the playback direction while the no-signal portion is detected, the song will always be played from the beginning, and this invention has a very large effect when applied to a tape recorder with a reciprocating playback function. It is something that plays. In addition, as a magnetic head for detecting a no-signal portion between signals recorded on tracks in the opposite direction, a magnetic head that is installed corresponding to the track and is not in use is used, so the configuration is simple. The invention has the advantage of simplicity. Furthermore, since the unused display element of the display element that is provided to display the playback direction is used as the display element that indicates that a no-signal area is detected, the configuration is simplified. The present invention is highly effective when applied to tape recorders, such as ultra-small tape recorders, which are susceptible to restrictions on the mounting position of display elements and the like.

[Brief explanation of the drawing]

The illustrated circuit is one embodiment of the display circuit of the present invention. Explanation of main drawing numbers, 1...first magnetic head, 2...
...Second magnetic head, 3...Third magnetic head, 4...
...Fourth magnetic head, 5...First changeover switch, 6
...Second changeover switch, 7...Third changeover switch, 8...Fourth changeover switch, 9...First preamplifier circuit, 11...First main amplification circuit, 12...Second changeover switch
Preamplifier circuit, 14... Second main amplifier circuit, 19...
...No-signal portion detection circuit, 21...Blinking drive circuit, 2
3...Fifth changeover switch, 25...Sixth changeover switch, 26...First light emitting diode, 27...Second light emitting diode.

Claims (1)

[Scope of utility model registration request] A tape recorder with a reciprocating playback function, which has a playback function in a first direction and a playback function in a second direction opposite to the first direction, and is configured to allow manual switching of the playback direction. a first magnetic head for reproducing the signal recorded on the track in the first direction;
A second magnetic head plays back the signal recorded on the track in the first direction, and when in the first direction playback mode, the signal played by the first magnetic head is input and the second magnetic head plays back the signal recorded on the track in the second direction. an amplifier circuit to which a signal reproduced by the second magnetic head is input when in a reproduction operation state; and an amplifier circuit to which a signal reproduced by the second magnetic head is input when in a reproduction operation state in the first direction; When in the reproducing operation state in the second direction, the signal reproduced by the first magnetic head is input;
and a no-signal portion detection circuit for detecting a no-signal portion between signals recorded on the magnetic tape, and a non-signal portion detection circuit that turns on when in a first direction playback operation state and performs a first direction playback operation. a first light emitting diode that indicates that the playback is being performed;
a second light emitting diode that indicates that a playback operation is being performed in the direction; and a blinking drive circuit that becomes operational when a detection signal associated with detection of a no-signal area is output from the no-signal area detection circuit. consisting of the first
When the no-signal portion is detected by the no-signal portion detection circuit while the reproducing operation is being performed in the direction, the second light emitting diode is made to blink by the output of the blinking drive circuit, and the reproducing operation in the second direction is performed. A tape recorder with reciprocating playback function, characterized in that when a no-signal portion is detected by the no-signal portion detection circuit during the playback, the first light emitting diode is made to blink by the output of the blinking drive circuit. display circuit.