JPH0738600B2 - Transmitter / receiver having earphone that also serves as a microphone - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transmitting / receiving device having an earphone that also serves as a microphone and is inserted into the ear.

[0002]

2. Description of the Related Art Currently used transceivers such as transceivers are equipped with a microphone and a speaker.
This device uses a microphone close to the mouth. The microphone in this position is extremely disturbing depending on how it is used. There is also a drawback that the microphone causes noise in the surroundings. Further, a transmitter / receiver having a handset including a microphone and a speaker is also used. This transmitter / receiver uses a microphone of a handset and a speaker close to the ear, and therefore has a drawback that both hands cannot be used freely.

These drawbacks can be solved by using the earphone as a microphone. Fortunately, most earphones can be used as microphones.
The earphone inserted in the ear can convert the sound transmitted from the mouth to the ear into an electric signal. A transmitter / receiver using an earphone that also serves as a microphone can be used most conveniently by automating switching between a transmitting state and a receiving state. However, a transmission / reception device using a microphone / earphone cannot easily switch between a transmission state and a reception state. The reason is that it is not possible to switch between the transmission state and the reception state by detecting the output signal of the microphone. That is, if the microphone is also used as the earphone, the output signal of the microphone and the output signal from the receiver main body cannot be distinguished from each other, so that the output signal of the earphone also serving as the microphone cannot switch between the transmitting state and the receiving state. Since the earphone signal is not input to the output signal of the microphone, the transmitting / receiving device equipped with the microphone and the earphone separately can switch between the transmitting state and the receiving state by the output signal of the microphone.

A transmission / reception switching circuit that can be used for a microphone-equipped earphone is described in Japanese Patent Publication No. 61-50539. The circuit described in this publication is shown in FIG. This circuit includes an amplifier circuit 2 for amplifying the output signal of the microphone / earphone 1, a waveform shaping circuit 3, a monostable multivibrator 4, a flip-flop 5, and a changeover switch 6 controlled by the flip-flop 5. ing. This circuit amplifies the output of the microphone / earphone 1 by the amplifier circuit 2, shapes the output by the waveform shaping circuit 3, triggers the monostable multivibrator 4 with the output of the waveform shaping circuit 3, and then outputs the monostable multivibrator 4 The flip-flop 5 is triggered by the output pulse of.

This circuit performs the following operation to switch between a transmission state and a reception state. When the changeover switch 6 is in the position shown by the solid line in the figure, the reception state is set. In this state, when the talker speaks in a normal state, the normal level signal is output from the microphone / earphone 1 to the waveform shaping circuit 3
Entered in. In this state, the waveform shaping circuit 3 does not input the output to the monostable multivibrator 4. When the speaker vibrates the microphone / earphone 1 greatly by engaging the teeth with each other, a large-level signal is input from the microphone / earphone 1 to the amplifier circuit 2. The output of the amplifier circuit 2 is input to the waveform shaping circuit 3, and the waveform shaping circuit 3
Outputs an output signal when the input exceeds a certain level, and the monostable multivibrator 4 is triggered by this output. Triggered monostable multivibrator 4
A pulse output having a fixed time width (0.5 to 1 second) is output and the output triggers the flip-flop 5. The flip-flop 5 triggered by the monostable multivibrator 4 is inverted to switch the changeover switch 6 to the chain line position. In this state, the transmission state is switched. In the transmitting state as well as in the receiving state, when a loud sound is input to the microphone / earphone 1 by engaging the teeth with each other, the output of the amplifier circuit 2 triggers the monostable multivibrator 4 to cause the monostable multivibrator to operate. The output pulse of 4 triggers the flip-flop 5, and the flip-flop 5 is inverted to switch the changeover switch 6 to the solid line position.

Further, this circuit is
A circuit for ignoring the trigger of the flip-flop 5 when a predetermined input is provided is provided. This circuit is also the amplifier circuit 7
, Waveform shaping circuit 8 and monostable multivibrator 9
It consists of and. When there is a predetermined input signal from the transmission line, the waveform shaping circuit 8 triggers the monostable multivibrator 9, and the output of the monostable multivibrator 9 causes the monostable multivibrator 4 to ignore the trigger.
The flip-flop 5 is not inverted.

[0007]

In the transmission / reception changeover circuit of this structure, a manual changeover switch can be omitted. However, since this circuit controls the changeover switch by the audio signal level input to the earphone that also serves as a microphone, switching between the transmission state and the reception state requires a special operation such as meshing teeth and cannot be easily used. . That is, this circuit is a circuit in which a manually operated changeover switch is changed to a voice signal level to be input to the earphone that also serves as a microphone. Therefore, in order to switch between the transmission state and the reception state, the talker needs to perform a specific operation, and it is not possible to switch between the transmission state and the reception state by carrying out an ordinary conversation, and anyone can easily perform this. There is a drawback that cannot be used for. In addition, the circuit is complicated and the manufacturing cost is high. Furthermore
This transmission / reception switching circuit is used when the other party is in the transmission state.
In addition, the talker bites his teeth, etc.
If you vibrate the phone too much, it switches from receiving to transmitting.
It has the drawback of being replaced. When this happens, both sides send
There is an adverse effect that it becomes a trusted state and you cannot talk. This evil
To prevent the other party from
Need to be prioritized to prevent switching to the transmission state.
There is. To achieve this, the other party must be in the sending state.
The other party's voice is output from the microphone / earphone
When you are there, do not switch to the sending state on this side
Need to With separate earphones and microphone
The switching circuit is switched by the other party at the output signal level of the earphone.
It can detect that it is in a communication state. Microphone
The transmission / reception switching circuit that uses dual-purpose earphones has a dual-purpose microphone.
Validate that the other party is in transmit state output level of Yahon
I can't put it out. It ’s an earphone that doubles as a microphone.
And the microphone are used together, the other party is
It functions as a microphone when there is no sound,
This is because the number is output. The present invention is an earphone that also serves as a microphone.
To receive when the other party is in the transmitting state.
State so that both are not in send state.
And are the first purposes.

Further, a technique for simultaneously calling by using an earphone in combination with a microphone is described in, for example, Japanese Patent Application Laid-Open No. 52-19904. However, in practice, it is extremely difficult to put this circuit to practical use. This circuit switches between transmission and reception in an extremely short period of time, and the pulsating noise generated at the time of switching significantly reduces the clarity.

[0009] An important objective is talker is talking normally, automatically transmitting state and the reception state of the present invention has been developed to further address this drawback, the present invention It is an object of the present invention to provide a transmission / reception device having a microphone-equipped earphone that can be switched between and and can be conveniently used by anyone.

Still another important object of the present invention is to provide a transmitting / receiving device having a microphone / earphone capable of switching between a transmitting state and a receiving state with a simple circuit.

[0011]

In order to achieve the above-mentioned object, a transmitting / receiving apparatus having a microphone / earphone according to the present invention has the following configuration (1) or (2).

(1) The transmission / reception switching circuit includes a microphone / earphone 1 incorporating a single electro-acoustic conversion element, and a receiver main body 10 having an output side connected to the microphone / earphone 1.
A transmitter main body 11 for modulating and transmitting a voice signal of the microphone / earphone 1; a receiver main body 10 and a transmission / reception switching circuit 12 for switching the operating state of the transmitter main body 11 between a transmission state and a reception state; A receiver level sensor 13 for detecting a reception level of the main body 10, a microphone signal transmission circuit 14 for transmitting an audio signal output from the microphone / earphone 1 under the control of the receiver level sensor 13, and a microphone signal transmission circuit 14. A microphone level sensor 15 that is connected to the transmitter body 11 and controls the transmission / reception switching circuit 12
It has and.

The receiver level sensor 13 switches the microphone signal transmission circuit 14 of the microphone circuit to the transmission state when the reception level is below a certain level to transmit the output of the microphone / earphone 1 to the transmitter main body 11, and in this state. , When the microphone level sensor 15 detects an audio signal above a certain level,
The transmission / reception switching circuit 12 is configured to be in the transmission state.

(2) The transmission / reception switching circuit includes a microphone / earphone 1 incorporating a single electric-acoustic conversion element, and a receiver main body 10 connecting an output side to the microphone / earphone 1
A transmitter main body 11 for modulating and transmitting a voice signal of the microphone / earphone 1; a receiver main body 10 and a transmission / reception switching circuit 12 for switching the operating state of the transmitter main body 11 between a transmission state and a reception state; A receiver level sensor 13 for detecting the reception level of the main body 10 and a microphone level sensor 15 for detecting the output level of the microphone / earphone 1 are provided.

A receiver level sensor 13 and a microphone level sensor 15 are connected to the transmission / reception switching circuit 12. The receiver level sensor 13 detects the reception level of the receiver main body 11 and this is below a certain level.
A transmission / reception device having a microphone / earphone configured to switch the transmission / reception switching circuit 12 to a transmission state when the microphone level sensor 15 detects the output level of the microphone / earphone 1 and detects that the output level is equal to or higher than a set level.

[0016]

[Action] A microphone-combined ear according to claim 1 of the present invention
The transmitter / receiver with a Perform the operation described below and
It is switched to the transmission state and the transmission state. A When the other party is in the transmission state ... In this state,
The following actions are performed, so no matter how loud you speak,
It does not go into trust.  When the other party is in the transmitting state, the receiver level sensor
Is in a receiving state above a certain level, the microphone signal
The transmission circuit is set to the non-transmission state.  Since the microphone signal transmission circuit is not transmitting,
Input level of the level sensor is lower than the set value.
It  Therefore, the microphone level sensor has a transmission / reception switching circuit.
Holds in the receiving state without switching to the transmitting state
It

B The other party is not in the transmitting state but in the receiving state.
When this state is reached ...
When you speak with a voice above the level, it switches from the receiving state to the transmitting state.
Can be replaced. When the other party is receiving, the receiver level sensor
Is in a receiving state below a certain level, the microphone signal
Put the transmission circuit in the transmission state. The microphone signal transmission circuit is
Speak into the dual-purpose earphones in a predetermined size and the microphone
The signal transmission circuit is the sound input from the earphone that also serves as a microphone.
The voice signal is amplified and output. The input level of the microphone level sensor is lower than the set value.
When it gets higher, the microphone level sensor sends the transmission / reception switching circuit.
Switch to the trusted state. Speak into the earphone that also serves as a microphone
Output level of the microphone signal transmission circuit
Therefore, the transmission / reception switching circuit is in the reception state.

A microphone according to claim 2 of the present invention
The transmitter / receiver with dual-purpose earphones operates as follows.
Then, the reception state and the transmission state are switched. A When the other party is in the transmission state ... In this state,
The following actions are performed, so no matter how loud you speak,
It does not go into trust. When the other party is in the transmitting state, the receiver level sensor
Is in a receiving state above a certain level, the microphone signal
The transmission circuit is set to the non-transmission state. Since the microphone signal transmission circuit is not transmitting,
Input level of the level sensor is lower than the set value.
It The transmission / reception switching circuit consists of a microphone level sensor and receiver
The bell sensor controls the reception status to the transmission status.
However, this transmission / reception switching circuit is a receiver level sensor.
The reception level is below a certain level, and the microphone
When the output level of the bell sensor is above the set level
It is possible to switch to the transmission state only for the receiver level.
The output level of the sensor is above a certain level, and
The output level of the black level sensor is below a certain level.
, The transmission / reception switching circuit does not switch to the transmission state,
It is kept in the receiving state.

B The other party is not in the transmitting state but in the receiving state.
When this state is reached ...
When you speak with a voice above the level, it switches from the receiving state to the transmitting state.
Can be replaced. When the other party is receiving, the receiver level sensor
Is in a receiving state below a certain level, the microphone signal
Put the transmission circuit in the transmission state. The microphone signal transmission circuit is
Speak into the dual-purpose earphones in a predetermined size and the microphone
The signal transmission circuit is the sound input from the earphone that also serves as a microphone.
The voice signal is amplified and output. The input level of the microphone level sensor is lower than the set value.
When it gets higher, the microphone level sensor sends the transmission / reception switching circuit.
Switch to the trusted state. The transmission / reception switching circuit is the receiver level sensor.
Controlled by both the sensor and the microphone level sensor,
If the output level of the receiver level sensor is below a certain level
Output of the microphone level sensor exceeds a certain level
And switch to the transmission state. Heading for earphones that also serve as microphones
When the speaking level becomes low, the receiver level sensor
The output is below a certain level, but the output level of the microphone signal transmission circuit is
Since the bell is lowered, the transmission / reception switching circuit is in the reception state.

[0020]

Embodiments of the present invention will be described below with reference to the drawings. However, the embodiments described below are examples of a transmission / reception device for embodying the technical idea of the present invention,
The transmission / reception device of the present invention does not specify the circuit configurations of the components to the following. The transmission / reception device of the present invention can be modified in various ways within the scope of the claims.

Further, in this specification, for easy understanding of the claims, the numbers corresponding to the members shown in the embodiments are referred to as "claims" and "means for solving the problems". It is added to the members shown in "Column". However, the members shown in the claims are not limited to the members of the embodiment.

The transmitter / receiver shown in FIG. 1 includes a microphone / earphone 1, a receiver main body 10, a transmitter main body 11, a transmission / reception switching circuit 12, a receiver level sensor 13, a microphone signal transmission circuit 14, and a microphone. And a level sensor 15.

The microphone / earphone 1 includes a single electro-acoustic conversion element 16 built-in, that is, a single diaphragm that is used both as a microphone and an earphone, such as a crystal earphone or a dynamic earphone. Can be used. However, the transmitting / receiving apparatus of the present invention does not specify the type of the microphone / earphone 1. As the microphone / earphone 1, all types of earphones that can be used with a microphone can be used.

The receiver body 10 can be any receiver that can receive a radio wave, detect it, and output it as an audio signal. The receiver main body 10 supplies the voice output to the microphone / earphone 1 and the voice is generated by the microphone / earphone 1. The receiver main body 10 detects the radio wave received in the receiving state, converts it into an audio signal, amplifies it, and outputs it to the microphone / earphone 1. When switched to the non-reception state, the receiver body 10 does not output the received audio signal to the microphone / earphone. To set the receiver body 10 to the non-reception state,
It is easy to turn off the power supplied to the receiver body 10. However, an audio output circuit (not shown) is provided on the output side of the receiver body 10 and the power of this audio output circuit is turned off, or an output switch provided on the main side of the audio output circuit is turned off to output audio. It can be turned off.

The transmitter main body 11 is an earphone 1 that also serves as a microphone.
The carrier wave is modulated with the audio signal input from the device and transmitted.
The transmitter body 11 and the receiver body 10 are used as transceivers. Therefore, the frequency of the radio wave transmitted by the transmitter main body 11 is adjusted to the frequency of the radio wave received by the receiver main body 10.

The transmission / reception switching circuit 12 switches the transmission / reception device between the transmission state and the reception state by setting either the receiver body 10 or the transmitter body 11 in the operating state. Transmission / reception switching circuit 12
Is provided with, for example, a changeover switch 17 connected between the receiver main body 10 and the transmitter main body 11 and the power supply. When the changeover switch 17 supplies power only to the receiver main body 10, it enters the receiving state, and it can supply power only to the transmitter main body 11 to enter the transmitting state.

The receiver level sensor 13 detects the signal level received by the receiver body 10. Receiver body 10
The signal level of can be detected at a low frequency level or a high frequency level. The receiver level sensor 13 that detects a low frequency level can rectify the output signal of the receiver body 10 and detect it as a DC level. To detect the high frequency level, A of the receiver body 10
A control voltage such as GC or AVC can be used. The control voltage of the receiver body 10 increases corresponding to the signal level received by the receiver body 10. Therefore, the control voltage decreases when the receiver body 10 does not receive a signal and increases when the signal is received. For this reason,
The magnitude of the control voltage can be measured to detect the signal level. Further, the receiver level sensor can also control the microphone signal transmission circuit by detecting the control signal modulated into the transmission radio wave. In this case, the control signal of the radio wave transmitted from the other party is modulated. When the receiver receives the control signal sent from the other party, it detects this control signal and turns off the microphone signal transmission circuit, and when the signal level of the control signal decreases and it is not received, the microphone signal transmission circuit To the transmission state.

The microphone signal transmission circuit 14 of the microphone circuit is
In the transmission state, that is, in the on state, the signal of the microphone / earphone 1 is input to the transmitter body 11, and in the off state, the signal of the microphone / earphone 1 is controlled not to be input to the transmitter body 11. Therefore, when the microphone signal transmission circuit 14 is off, the signal of the microphone / earphone 1 is not input to the transmitter main body 11. The microphone signal transmission circuit 14 is
The receiver level sensor 13 controls the on / off state. When a signal of a predetermined level or higher is input to the receiver main body 10, the microphone signal transmission circuit 14 is turned off, and the output of the microphone / earphone 1 is transmitted to the transmitter main body 11.
Do not enter in.

The receiver level sensor 13 detects that the input level of the receiver body 10 is below the set value,
In this state, the microphone signal transmission circuit 14 is turned on.
Although not shown, a changeover switch for selectively changing the microphone / earphone to either the receiver body or the transmitter body can be used for the microphone signal transmission circuit. When the changeover switch connects the microphone / earphone to the receiver body, the transmitter body is separated from the microphone / earphone.
On the contrary, when the microphone / earphone is connected to the transmitter body, the receiver body is separated from the microphone / earphone.
When the microphone / earphone is connected to the transmitter body, a signal from the microphone / earphone is transmitted to the transmitter.

The microphone level sensor 15 is connected between the output of the microphone signal transmission circuit 14 and the transmitter main body 11. The microphone level sensor 15 detects the output level of the microphone signal transmission circuit 14 in the ON state and controls the transmission / reception switching circuit 12. Microphone level sensor 15
When the output level of the microphone signal transmission circuit 14 exceeds the set value, the transmission / reception switching circuit 12 is set to the transmission state. Also,
When the output level of the microphone signal transmission circuit 14 is below the set level, the transmission / reception switching circuit 12 is controlled to the receiving state.
The microphone level sensor 15 includes the microphone signal transmission circuit 14
Is rectified by the diode and the output level of the microphone signal transmission circuit 14 is detected at the DC level.

The transmission / reception apparatus shown in FIG. 1 performs the following operations to communicate. When the receiver body 10 is in a state of receiving a signal, the receiver level sensor 13 detects this and turns off the microphone signal transmission circuit 14. In this state, the output of the receiver main body 10 is transmitted to the microphone / earphone 1 and reproduces the sound received by the microphone / earphone 1. When the microphone signal transmission circuit 14 is off, the output of the microphone / earphone 1 is not input to the transmitter main body 11,
The output level of the microphone signal transmission circuit 14 becomes the set value or less. It is detected by the microphone level sensor 15 that the output level of the microphone signal transmission circuit 14 is below the set level, and the microphone level sensor 15 holds the transmission / reception switching circuit 12 in the reception state. When the transmission / reception device of the other party stops the transmission of the radio wave or the voice is not transmitted, the reception level of the receiver main body 10 is lowered, and this is the receiver level sensor 13
Detected by. The receiver level sensor 13 switches the microphone signal transmission circuit 14 from the off state to the on state, and supplies the output of the microphone / earphone 1 to the transmitter body 11. In this state, when a person who inserts the microphone / earphone 1 into the ear makes a voice, the voice is transmitted to the human body and input to the microphone / earphone 1, and the microphone / earphone 1 outputs a voice signal. When a voice signal is output from the microphone / earphone 1, the microphone level sensor 15 detects this signal,
The transmission / reception switching circuit 12 is set to the transmission state. Even if the microphone signal transmission circuit 14 is turned on, the microphone level sensor 15 does not set the transmission / reception switching circuit 12 to the transmission state unless the person who inserts the microphone / earphone 1 into his / her ear does not generate a voice. This is because the microphone level sensor 15 puts the transmission / reception switching circuit 12 in the transmission state at a certain level or higher. Therefore, it is kept in the receiving state unless the talker speaks. When the speaker stops producing voice, the microphone level sensor 15 detects this and switches the transmission / reception switching circuit 12 to the reception state. Hereinafter, the operations from to are repeated to switch between the transmission state and the reception state.

FIG. 2 shows a transmission / reception apparatus in which the microphone level sensor alone does not control the transmission / reception switching circuit. In this transmission / reception device, both the receiver level sensor 13 and the microphone level sensor 15 control the transmission / reception switching circuit 12. This circuit omits the microphone signal transmission circuit by controlling the transmission / reception switching circuit 12 with both the receiver level sensor 13 and the microphone level sensor 15.
Therefore, the output of the microphone / earphone 1 is always input to the transmitter main body 11.

In this circuit, when the reception level of the receiver main body 10 decreases, the audio signal level output from the receiver main body 10 to the microphone / earphone 1 decreases. Therefore, when a voice signal is input to the transmitter main body 11 in this state, the voice signal input from the outside is converted into an electric signal by the microphone / earphone 1 serving as a microphone. That is, it is an audio signal produced by a person who inserts the microphone / earphone 1 into the ear. In other words, when trying to send, the transmitter main body 1
The voice signal input to 1 is obtained by converting the voice of the sender into an electric signal by using the microphone / earphone 1 as a microphone. Therefore, it is not necessary to use a microphone signal transmission circuit that transmits the output of the microphone / earphone 1 to the transmitter main body 11 when transmitting. However, as in the device shown in FIG. 1, it is possible to provide a microphone signal transmission circuit between the microphone-equipped earphone 1 and the transmitter main body 11 and control this with the receiver level sensor 13.

This transmitting / receiving device operates in the following states. When the receiver body 10 is in the state of receiving a signal, the receiver level sensor 13 detects this and holds the transmission / reception switching circuit 12 in the reception state. The output of the receiver body 10 is transmitted to the microphone / earphone 1 and reproduces the sound received by the microphone / earphone 1. The voice output of the receiver main body 10 is input to the transmitter main body 11, but the transmission / reception switching circuit 12 is in the reception state and the transmitter main body 11 is not transmitting. For this reason, the transmitter main body 11 does not modulate the radio wave with the input signal and transmit it. When the transmission / reception device of the other party stops the transmission of the radio wave or the voice is not transmitted, the reception level of the receiver main body 10 is lowered, and this is the receiver level sensor 13
, The receiver level sensor 13 outputs a transmission signal to the transmission / reception switching circuit 12. In this state, when a person who inserts the microphone / earphone 1 into the ear makes a voice, the voice is transmitted to the human body and input to the microphone / earphone 1, and the microphone / earphone 1 outputs a voice signal. When an audio signal is output from the microphone / earphone 1, this signal is detected by the microphone level sensor 15. At this time, the microphone level sensor 15 outputs a transmission signal to the transmission / reception switching circuit 12 when it detects an input signal above the set level. In this state, the transmission / reception switching circuit 12 receives the transmission signal from the receiver level sensor 13 and the microphone level sensor 15. The microphone level sensor 15 does not output a transmission signal unless a person who inserts the microphone / earphone 1 into his / her ear does not generate a voice. This is because the microphone level sensor 15 puts the transmission / reception switching circuit 12 in the transmission state at a certain level or higher. Therefore, the microphone level sensor does not output the transmission signal unless the talker speaks. When transmission signals are input from both the receiver level sensor 13 and the microphone level sensor 15 to the transmission / reception switching circuit 12, the transmission / reception switching circuit 12 sets the transmission main body to the voice input to the microphone / earphone 1 as the transmission state. Send from When the speaker stops producing voice, the microphone level sensor 15 detects this, the microphone level sensor 15 stops outputting the transmission signal, and the transmission / reception switching circuit 12 is switched to the reception state. Hereinafter, the operations from to are repeated to switch between the transmission state and the reception state.

The transmitter / receiver shown in FIGS. 1 and 2 automatically switches between the transmitting state and the receiving state by the receiver level sensor and the microphone level sensor, but a standby switch 18 for manually switching is provided. When you need it,
It is also possible to switch between transmission and reception with the manual standby switch 18.

[0036]

The transmitter / receiver of the present invention can automatically switch between the transmission state and the reception state by using the earphone that also serves as a microphone to talk in a normal state. No special operation is required to switch between the transmitting state and the receiving state. Therefore, there is a feature that anyone can use it easily, easily and conveniently.

Furthermore, the transmitting / receiving device of the present invention has a simple circuit configuration, without degrading intelligibility, and
There is a feature that it is possible to switch between the transmitting state and the receiving state without hearing the conversation of the other party. It is the invention
The transmitter / receiver of the device uses the earphone that also serves as a microphone.
However, if the other party is in the sending state, this is the receipt
It is kept in a state and both are not in the transmission state.
It

[Brief description of drawings]

FIG. 1 is a block diagram of a transmitter / receiver showing an embodiment of the present invention.

FIG. 2 is a block diagram of a transmitter / receiver showing an embodiment of the present invention.

FIG. 3 is a circuit diagram showing an example of a conventional transmission / reception switching circuit.

[Explanation of symbols]

1 ... Microphone / earphone 2 ... Amplifying circuit 3 ... Waveform shaping circuit 4 ... Monostable multivibrator 5 ... Flip-flop 6 ... Changeover switch 7 ... Amplifying circuit 8 ... Waveform shaping circuit 9 ... Monostable multivibrator 10 ... Receiver main body 11 ... Transmitter main body 12 ... Transmission / reception switching circuit 13 ... Receiver level sensor 14 ... Microphone signal transmission circuit 15 ... Microphone level sensor 16 ... Electric-acoustic conversion element 17 ... Changeover switch 18 ... Standby switch

Claims (2)

[Claims] 1. A microphone / earphone (1) incorporating a single electro-acoustic conversion element (16), and a receiver body (10) having an output side connected to the microphone / earphone (1).
And a transmitter main body (11) that modulates and transmits a voice signal of the microphone / earphone (1), and switches the operating states of the receiver main body (10) and the transmitter main body (11) between a transmission state and a reception state. The output of the microphone / earphone (1) controlled by the transmission / reception switching circuit (12), the receiver level sensor (13) for detecting the reception level of the receiver body (10), and the receiver level sensor (13). A microphone signal transmission circuit (14) for transmitting a voice signal, and a microphone level sensor connected between the microphone signal transmission circuit (14) and the transmitter body (10) to control the transmission / reception switching circuit (12). (15), the receiver level sensor (13) switches the microphone signal transmission circuit (14) to a transmission state when the reception level is below a certain level to switch the microphone earphone ( Transmitter body an output signal of) (1
0) to the microphone level sensor (1
A transmitter / receiver having a microphone / earphone configured so that 5) detects an audio signal above a certain level and the transmission / reception switching circuit (12) is switched to a transmission state. 2. A microphone / earphone (1) containing a single electro-acoustic conversion element (16), and a receiver body (10) having an output side connected to the microphone / earphone (1).
And a transmitter main body (11) that modulates and transmits a voice signal of the microphone / earphone (1), and switches the operating states of the receiver main body (10) and the transmitter main body (11) between a transmission state and a reception state. A transmission / reception switching circuit (12), a receiver level sensor (13) that detects the reception level of the receiver body (10), and a microphone level sensor (15) that detects the output of the microphone / earphone (1). The receiver level sensor (13) and the microphone level sensor (15) are connected to the transmission / reception switching circuit (12), and the receiver level sensor (13) detects the reception level of the receiver body (11). This is located below a certain level, or to
On the other hand, when the microphone level sensor (15) detects the output level of the microphone / earphone and detects that the output level is higher than the set level, the microphone / earphone configured to switch the transmission / reception switching circuit (12) to the transmitting state. A transmitter / receiver having.