JPH07177206A - Telephone system - Google Patents

Abstract

PURPOSE:To provide excellent transmission and reception by providing transmitting and receiving circuits for internal transmitter/receivers and an external transmitter receiver and switching transmitting and receiving circuits by the external transmitter receiver. CONSTITUTION:When the external transmitter/receiver is not connected to an external transmitted/receiver connection part 105, the external transmitter/ receiver nonconnection is reported from an external receiver connection detection part 108 to a control part 113. A transmitting/receiving circuit switching part 109 connects a circuit to the side of internal transmitter receivers 101 and 102 according to the report from the control part 113 and a receiving circuit 104 provides excellent transmission and reception matching characteristics of the internal transmitter receivers 101 and 102. Then when the external transmitter/receiver is connected to the connection part 105, that is reported from the detection part 108 to the control part 113. The switching part 109 connects the circuit to the side of the external transmitter receiver 105 according to the report. At this time, a transmitting circuit 106 and a receiving circuit 107 are placed in an excellent transmission and reception state matching characteristics of the external transmitter receiver.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a telephone device to which an external handset can be connected.

[0002]

2. Description of the Related Art Conventionally, in a telephone device to which an external handset can be connected, as shown in FIG.
Even when the external handset is connected to 05, the same transmitting circuit 203 and receiving circuit 204 are used as when using the built-in handset.

An operation example of a conventional cordless telephone to which an external handset can be connected will be shown below.

In the conventional transmitter / receiver circuit, when the external transmitter / receiver is not connected, the transmitter / receiver 101 and the transmitter / receiver circuit 20 are connected through the contact 201 in the external transmitter / receiver connection section (105).
3 is connected. Similarly, the reception circuit 204 and the reception device 102 are connected through the contact 202.

When the external handset is connected, the contacts 201 and 202 are not in contact with each other due to the insertion pressure of the external handset connection terminal, the handset 101 and the handset 102 are cut off, and the external handset and the handset are connected. The circuit 203 and the receiving circuit 204 are connected.

As described above, in the conventional example, since the transmitter and receiver circuits are shared by the built-in and external transmitters and receivers, the characteristics of the transmitter and receiver circuits are moderate, or the built-in transmitter and receiver are used. I tried to use an external handset with the same characteristics.

[0007]

However, in the above-mentioned conventional example, even when the external handset is used, the same transmitting and receiving circuits are used as when the built-in handset is used. It could not be used unless it was an external handset with the same characteristics as the handset.

Further, since the structural difference between the built-in handset and the external handset (for example, the distance between the handset and the mouth) cannot be corrected, it depends on whether the built-in handset is used or the external handset is used. The transmission level and the reception level were different.

[0009]

According to the present invention, in a telephone device to which an external handset can be connected, by having an external handset connection detection section and a sending circuit switching means, the characteristics of the external handset can be improved. This makes it possible to provide the most suitable transmitting circuit.

Further, by having the external transmitter / receiver connection detection unit and the receiver circuit switching means, it is possible to provide an optimum receiver circuit that matches the characteristics of the external receiver circuit.

[0011]

1 is a block diagram of a cordless telephone handset representing the present invention.

Reference numeral 101 is a built-in transmitter, 102 is a built-in receiver, 103 is a built-in transmitter circuit, 104 is a built-in receiver circuit, 105 is an external receiver connection section, and 106 is an external receiver circuit. Reference numeral 107 denotes an external handset reception circuit, and reference numeral 108 denotes an external handset connection detection unit that mechanically detects that the external handset is connected and notifies the control unit (113).

Reference numeral 109 is a transmission / reception circuit switching section for switching the communication path to the built-in transmission / reception handset depending on whether or not an external transmission / reception handset is connected, 110 is a keypad for inputting dial data and the like, and 111 is It is a signal processing unit that processes data and voice to be transmitted and data and voice to be received by a filter or the like in an appropriate form.

Reference numeral 112 is a control data modulator / demodulator for modulating / demodulating control data via a modem, 113 is a controller for controlling the operation of the cordless telephone handset, 114 is a signal for modulating a signal to be transmitted, and a signal for receiving is demodulated. A high-frequency transmitting / receiving unit that communicates with the base unit, 115 is a battery that supplies power to the cordless telephone handset, and 116 is an antenna.

FIG. 3 shows a circuit example of the transmitting circuits 103 and 106.

By adjusting the resistors 301, 302, 303 and the capacitor 304 to appropriate values, the impedance of the transmitter and the impedance of the transmitter are combined, and the difference in signal level due to the difference between the distance between the transmitter and the mouth is corrected. You can

Next, the operation of the embodiment of the present invention will be described according to the actual operation.

If the external handset is not connected to the external handset connection unit (105), the external handset connection detection unit (108) notifies the control unit (113) that the external handset is not connected. It In that state, the transmission / reception circuit switching unit (109) connects the circuit to the built-in transmission / reception handsets (101) and (102) by the notification from the control unit (113). Transmitting circuit (103) and receiving circuit (104)
Is optimized for the characteristics of the built-in handset.

Next, when the external handset is connected to the external handset connection section (105), the external handset connection detection section (1)
08) notifies the control unit (113) that the external handset is connected. In this state, the transmission / reception circuit switching unit (109) connects the circuit to the external transmission / reception device side (105) according to the notification from the control unit (113).

At this time, the transmitter circuit (106) and the receiver circuit (107) are optimally matched to the characteristics of the external transmitter / receiver.

Here, as an example of the built-in receiver (102) and the receiver circuit (104), there are a ceramic receiver that does not require a large current for driving, and a circuit that outputs it in a balanced manner.

As an example of the receiver circuit (107) and the external receiver, there are a dynamic receiver which requires a current for driving and a circuit which outputs it unbalanced.

As described above, according to the present embodiment, by properly setting the characteristics of the transmitting circuits 103 and 106, the transmission of a sufficient sound quality sets the characteristics of the receiving circuits 104 and 107 appropriately. As a result, it is possible to receive a voice with sufficient sound quality.

In the embodiment shown in FIG. 1, two operational amplifiers are used. However, as shown in FIG. 4, the operational amplifiers of the transmitter circuits (103) and (106) are also used and built-in. When using the transmitter (101), resistors 401, 40
When using 2 and an external transmitter, resistors 403, 40
Even if the circuit configuration using 4 is used, the same effect can be obtained.

Further, although the cordless telephone device has been described in the present embodiment, the same effect can be obtained by replacing the voice circuit of the wired telephone device.

[0026]

As described above, by having the external transmitter / receiver connection detection unit and the transmitter circuit switching means, the structural and electrical characteristics of the external transmitter and the built-in transmitter are corrected to improve the sound quality. It is possible to transmit signals of the same level, and it is possible to connect an internal transmitter and an external transmitter having different characteristics.

Further, by having the external transmitter / receiver connection detection unit and the receiver circuit switching means, the structural and electrical characteristics of the external receiver and the built-in receiver are corrected, and the sound pressure is released at the same level of sound quality. It is possible to make sound, and it is possible to connect an external handset having different characteristics from the built-in handset.

[Brief description of drawings]

FIG. 1 is a block diagram of a cordless telephone handset embodying the present invention.

FIG. 2 is a diagram of a conventional handset circuit and handset switch unit.

FIG. 3 is a circuit diagram of a transmitter circuit.

FIG. 4 is a circuit diagram of another transmitting circuit.

[Explanation of symbols]

 101 Built-in Handset 102 Built-in Handset 103 Sending Circuit for Built-in Handset 104 Reception Circuit for Built-in Handset 105 External Handset Connection Section 106 External Handset Transmission Circuit 107 External Handset Reception Circuit 108 External Handset Connection Detection Section 109 Transmission / reception circuit switching unit

Claims (2)

[Claims] 1. In a telephone device having a built-in handset and capable of connecting an external handset, an external handset connection detection unit, a built-in handset transmitter circuit, and an external handset transmitter circuit. A telephone device having a transmitter circuit switching means for switching to a transmitter circuit to be used among the transmitter circuits. 2. In a telephone device having a built-in handset and capable of connecting an external handset, an external handset connection detection unit, an external handset receiving circuit, and a receiving circuit to be used among the receiving circuits are switched. A telephone device having a receiving circuit switching means.