JPS6327356Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a tape recorder, and is particularly intended to provide a tape recorder with an intercom function.

Generally popular tape recorders are equipped with an internal microphone and an internal speaker, as well as an external microphone jack into which an external microphone plug is inserted, and an external speaker jack into which an external speaker plug such as a headphone is inserted. We are prepared. In addition to such a configuration, the present invention also allows the operation and operation of a tape recorder to be controlled from the outside.
The intercom operation is performed using a tape recorder equipped with a remote jack provided to control inoperation, and will be described in detail below with reference to the drawings.

Figure 1 shows an embodiment of the present invention, in which 1 is an internal microphone attached to a tape recorder, 2 is an external microphone jack into which the external microphone plug is inserted, and 3 is a recording head. Magnetic heads 4, 5, 6, and 7 for reproduction are recording/reproducing switching switches, and the illustrated state is the reproducing state. 8 is a preamplifier circuit to which a reproduction signal from the microphone or recording/reproduction magnetic head 3 is applied and amplifies the signal; 9;
a variable resistor 10 to which the output signal of the preamplifier circuit 8 is applied and adjusts the level of the signal;
1 is a main amplifier circuit to which a signal level-adjusted by the variable resistor 9 is applied and amplifies the signal; 11 is attached to a tape recorder and to which the output signal of the main amplifier circuit 10 is applied. An internal speaker, 12 is an external speaker jack into which a plug for an external speaker such as a headphone is inserted, and 13 is a recording amplifier circuit that is activated during recording operation, and the output signal of the preamplifier circuit 8 is used as a recording signal. It is connected so that the input signal and the output signal thereof are applied to the recording/reproducing magnetic head 3. 14 is a motor for driving the magnetic tape; 15 is a motor drive circuit for driving the motor 14 at a constant speed; and 16 is a switch that is opened when the tape recorder is stopped and closed when an operation such as playback is performed. . Reference numeral 17 denotes a remote jack into which a remote plug for controlling the power supply to the amplifier circuits such as the preamplifier circuit 8, the electric motor 14, etc. is inserted from the outside. 18,1
9, 20 and 21 are selection switches for switching between use of the tape recorder and use of the intercom;
The illustrated state is a tape recorder in use. Reference numerals 22, 23, and 24 are non-lock type internal conversation switches which are switched in conjunction with each other during conversation operation and which self-return to the original state when the operating force is cut off, and the illustrated state is the non-operated state.

Figure 2 shows an intercom adapter used in combination with the tape recorder of the present invention, 25 is an intercom microphone, 26
is a first plug connected to the intercom microphone 25 by a cord 27 and inserted into the external microphone jack 2. A second plug 28 is connected to the intercom speaker 29 by a cord 30 and is inserted into the external speaker jack 12. Reference numeral 31 denotes an external conversation switch which is provided on the adapter side and is closed during conversation operation, and is a non-lock type switch which is opened when the operating force is cut off. A third plug 32 is connected to the external conversation switch 31 by a cord 33 and is inserted into the remote jack 17.

The present invention is constructed as described above, and its operation will be explained next. First, select switch 18,1
The operation when 9, 20, and 21 are on the illustrated tape recorder use side and the intercom adapter shown in FIG. 2 is not used will be described. When the user performs a playback operation, the drive mechanism of the tape recorder enters the drive state for playback, and the switch 16 is closed to supply power to the amplifier circuit and motor drive circuit 15. The reproduced signal reproduced by the recording/reproducing magnetic head 3 is input to the preamplifier circuit 8 through the recording/reproducing changeover switch 4 and the selection switch 18, where it is amplified and then applied to the variable resistor 9. The reproduced signal applied to the variable resistor 9 is level-adjusted and then sent to the main amplifier circuit 10.
is input and amplified. The reproduced signal amplified by the main amplifier circuit 10 is sent to a conversation switch 23 - a selection switch 19 - an external speaker jack 12
The signal is applied to the internal speaker 11 through the switching contact piece 12a, and the sound is emitted. With this playback operation, the user can hear the reproduced sound from the internal speaker 11, but if the headphone plug is inserted into the external speaker jack 12, the signal path to the internal speaker 11 is cut off, and the user can hear the reproduced sound from the headphone. You can listen to the playback sound by turning it on.

Although the reproduction operation is performed as described above, the recording operation will be explained next. When a recording operation is performed, the recording/reproduction changeover switches 4, 5, 6, and 7 are switched to the opposite side from the state shown, and the switch 16 is closed to establish a recording operation state. The recording signal obtained from the internal microphone 1 is input to the preamplifier circuit 8 through the switching contact piece 2a of the external microphone jack 2, the conversation switch 22, the recording/playback selection switch 4, and the selection switch 18, where it is amplified. . The recording signal amplified by the preamplifier circuit 8 is input to the recording amplifier circuit 13 in operation via the recording/playback switch 7, where it is amplified and then output as a bias signal from a bias oscillation circuit (not shown). At the same time, the signal is applied to the recording/playback magnetic head 3 and recorded on the magnetic tape. Furthermore, the recording signal amplified by the preamplifier circuit 8 is transferred to a variable resistor 9.
After the level is adjusted, the sound is input to the main amplifier circuit 10 and amplified, but since the ground side terminal of the internal speaker 11 is not grounded by the recording/playback switch 6, no sound is emitted from the internal speaker 11. No howling occurs. In such a state, if the headphone plug is inserted into the external speaker jack 12, the recorded signal amplified by the main amplifier circuit 10 can be heard as a monitor signal. In this way, the recording signal obtained from the internal microphone 1 is recorded, but if the plug of the external microphone is inserted into the external microphone jack 2, the recording signal obtained from the external microphone instead of the internal microphone 1 is recorded. is input to the preamplifier circuit 8, and the recording signal obtained from the external microphone is recorded.

As described above, the playback and recording operations of the tape recorder are performed, but power supply to the amplifier circuit and motor drive circuit 15 is controlled by inserting the remote plug into the remote jack 17 and opening/closing the external remote switch. This means that the playback and recording operations are controlled remotely from the tape recorder.

Although the tape recorder operates as described above, the operation as an intercom will be explained next. When the intercom is in use, the selection switches 18, 19, 20, and 21 are switched to the opposite side from the state shown, and the first plug 26, second plug 28, and third plug 32 of the intercom adapter are connected to the external microphone jack 2, respectively. , inserted into the external speaker jack 12 and remote jack 17. In this state, the switching contact piece 17a of the remote jack 17 is open, so that the power supply to the preamplifier circuit 8 and the main amplifier circuit 10 is cut off. Also, in this state, the signal from the intercom microphone 25 is input to the preamplifier circuit 8 through the external microphone jack 2, the conversation switch 22, and the selection switch 18, and the output signal from the main amplifier circuit 10 is The signal is applied to the internal speaker 11 through the conversation switch 23 and the selection switch 19. Therefore, in such a state, when the other party closes the external conversation switch 31 in order to have a conversation, power is supplied from the power supply circuit 34 to the preamplifier circuit 8 and the main amplifier circuit 10 through the external conversation switch 31 and the selection switch 21. Since the preamplifier circuit 8 and the main amplifier circuit 10 are supplied with the signal, the preamplifier circuit 8 and the main amplifier circuit 10 become operational.
Therefore, the voice from the other party is transmitted from the intercom microphone 25 to the external microphone jack 2-.
The sound is applied to the internal speaker 11 through the conversation switch 22 - selection switch 18 - preamplifier circuit 8 - variable resistor 9 - main amplifier circuit 10 - conversation switch 23 - selection switch 19, and is emitted. Voices can be heard.

The voice from the other party is transmitted to the user in this way. Next, the operation of transmitting the user's voice to the other party will be explained. This operation is performed by the user operating the conversation switches 22, 23 and 24 to switch to the opposite side from the state shown. In such a state, power from the power supply circuit 34 is supplied to the preamplifier circuit 8 and the main amplifier circuit 10 through the conversation switch 24 and the selection switch 21,
The preamplifier circuit 8 and main amplifier circuit 10 become operational. Therefore, in such a state, the user's voice input from the internal microphone 1 is transmitted through the conversation switch 22 - selection switch 18 - preamplifier circuit 8 - variable resistor 9 - main amplifier circuit 10 - conversation switch 2.
3- The sound is applied to the intercom speaker 29 through the external speaker jack 12 and emitted, so that the other party can hear the user's voice.

As explained above, the conversation switches 22, 2
By alternately operating 3 and 24 and the external conversation switch 31, the user can perform a so-called intercom operation to converse with the other person.
If they are operated at the same time, the conversation switch 22
The signal from the internal microphone 1 is input to the preamplifier circuit 8, and the conversation switch 23 applies the output signal of the main amplifier circuit 10 to the intercom speaker 29. That is, priority is given to the operation of transmitting the user's voice to the other party.

The operation as a tape recorder and an intercom is performed as described above. Next, the operation when recording a conversation via an intercom onto a magnetic tape will be explained. If you perform a recording operation while the above-mentioned intercom operation is in progress, switch 1 will be activated.
6 is closed, and the recording/playback switch 4,
5, 6 and 7 are switched to the recording side, which is the opposite side of the illustrated state. When this operation is performed, the user's voice and the other party's voice, which are the outputs of the preamplifier circuit 8, are input to the recording amplifier circuit 13 through the recording/playback switch 7, so that the signals are transferred to the recording/playback magnetic head. 3 and is recorded on the magnetic tape. Conversation recording operation is performed in this way, but since power is supplied to amplifier circuits 8, 10, 13 and motor drive circuit 15 through conversation switch 24 or external conversation switch 31, the tape recorder's recording operation is performed in the same way as conversation recording. This is done only when the magnetic tape is actually being carried out, and unnecessary running of the magnetic tape and wasteful consumption of power can be prevented.

As explained above, the present invention is configured to perform intercom operation using a tape recorder equipped with an internal microphone, an external microphone jack, an internal speaker, an external speaker jack, and a remote jack.
It requires fewer additional parts and can be manufactured at low cost. In addition, the present invention is designed to supply power to the preamplifier circuit and main amplification circuit, which perform the signal amplification operation when the intercom is in use, through an internal conversation switch or an external conversation switch that is pressed during conversation operation. This feature allows power to be consumed only when conversation is being performed, which prevents unnecessary power consumption and allows batteries to be used as a power source. When applied to a tape recorder, it has a very large effect.

[Brief explanation of the drawing]

Figure 1 is a circuit diagram showing one embodiment of the present invention;
The figure shows an example of an intercom adapter. Explanation of main figure numbers, 1...Internal microphone,
2...Jack for external microphone, 3...Magnetic head for both recording and playback, 8...Preamplifier circuit, 1
0... Main amplifier circuit, 11... Internal speaker, 1
2... Jack for external speaker, 17... Remote jack, 18, 19, 20, 21... Selection switch, 22, 23, 24... Switch for internal conversation, 25... Microphone for intercom,
29... Speaker for intercom, 31... Switch for external conversation, 34... Power supply circuit.

Claims (1)

[Scope of utility model registration request] In a tape recorder equipped with an internal microphone, an external microphone jack, an internal speaker, an external speaker jack, and a remote jack, a signal obtained from the internal microphone when a plug is not inserted into the external microphone jack. a preamplifier circuit to which a signal obtained from an external microphone is input when a plug is inserted into the jack, and a signal amplified by the preamplifier circuit is applied to the internal speaker. or the main amplifier circuit to which the external speaker is connected as a load when the plug is inserted into the external speaker jack, and the main amplifier circuit to which the external speaker is connected as a load, and the main amplifier circuit to which the external speaker is connected as a load; a selection switch that applies the output signal of the main amplification circuit to the internal speaker regardless of whether a plug is inserted; an input operation for a signal that is switched during conversation operation and input to the preamplification circuit; and an output signal of the main amplification circuit. a non-lock type internal conversation switch connected to control the output operation to the internal speaker or the external speaker jack and the power supply operation to the amplifier circuit, and which automatically returns to the original state when the operating force is cut off; , plugs inserted into the external microphone jack, external speaker jack, and remote jack, respectively, and connected to the intercom microphone, the intercom speaker, and a non-locking external conversation switch that can be switched during conversation operation. an intercom adapter having a preamplifier circuit and A tape recorder with an intercom function, characterized in that power is supplied to the main amplifier circuit.