JPH10327266A - Modem device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To execute a monitoring processing in MODEM even if a monitor device is provided outside by providing a circuit where a relay is connected in parallel to a capacitor and a resistor, which are connected in series. SOLUTION: When the relay 16 is turned on, a signal from a telephone line or the terminal 12 of a facsimile equipment with telephone function is transmitted to MODEM 1 through an insulating transformer. A signal from MODEM 11 is transmitted to the telephone line or the facsimile equipment with telephone set. When the relay 16 is turned off, the signal from the telephone line or the terminal 12 of the facsimile equipment with telephone set is not transmitted to MODEM 11 via the relay 16. On the other hand, the signal from MODEM 11 is not, transmitted to the telephone line or the terminal 12 of the facsimile equipment with telephones via the relay 16. Since the resistor 14 and the capacitor 15 exist in parallel to the relay 16, AC signals can be transmitted to them.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a modem connected to a terminal such as a telephone line or a facsimile machine with a telephone.

[0002]

2. Description of the Related Art Conventionally, a configuration of a modem device for monitoring a telephone line or a terminal is shown in FIG.
Are known.

FIG. 4 shows a configuration of a conventional modem device. In FIG. 4, during normal operation, switches 6, 7, and 8 are connected as shown by solid lines, and terminal unit 1 transmits data to modem unit 2 via signal line A. The modem unit 2 transmits data to the terminal unit 1 via the signal line B. To monitor these signals, a monitoring device is connected to the connector 9.
Since the signal on the signal line A is supplied to the connector 9 by the driver 4 and the signal on the signal line B is supplied by the driver 3, the monitor device can monitor these signals.

[0004]

However, the conventional modem device is required to have a monitor device outside the modem device as described above.

[0005]

According to the present invention, there is provided a modem device comprising: (1) a capacitor and a resistor connected in series between a terminal such as a telephone line or a facsimile machine with a telephone and an insulating transformer; And (2) a capacitor and a resistor are connected in series between a terminal such as a telephone line or a facsimile machine with a telephone and an insulating transformer. And a means for detecting and processing a certain signal in the modem, and a means for detecting and processing a certain signal in the modem. A first relay for selecting whether the terminal or modem is to be connected to a telephone line or a DC power supply, and controlling the connection between the modem and the telephone line. 2, a circuit in which a capacitor and a resistor are connected in series with the second relay, a third relay for controlling whether or not to bypass the DC loop forming circuit, and a terminal such as a facsimile apparatus with a telephone. And a fourth relay for controlling a ring signal to be transmitted to the communication device.

With these configurations, it is possible to perform monitoring processing in the modem without having a monitoring device outside the modem device.

[0007]

DETAILED DESCRIPTION OF THE INVENTION The invention according to claim 1 of the present invention is to connect the telephone line or a capacitor and a resistor in series between a telephone line or a terminal such as a facsimile apparatus with a telephone and an insulating transformer, and It is configured to include a circuit in which a relay is connected in parallel to the series-connected capacitor and resistor, and the modem can be used without taking a configuration having a monitor device outside the modem device, which has conventionally been a problem. It has the effect of monitoring.

According to a second aspect of the present invention, a capacitor and a resistor are connected in series between a terminal such as a telephone line or a facsimile apparatus equipped with a telephone and an insulating transformer, and the capacitor and the resistor connected in series are connected in parallel with the resistor. It has a circuit to which a relay is connected, and a means for detecting and processing a certain signal in the modem, and has a configuration in which a monitor device is provided outside the modem device, which has been a problem in the past. Even if it is not, it has the effect of performing monitor processing in the modem.

According to a third aspect of the present invention, a first relay for selecting a telephone line or a DC power supply to be connected to a terminal such as a facsimile apparatus with a telephone or a modem, and a connection between the modem and the telephone line. A second relay for controlling, a circuit in which a capacitor and a resistor are connected in series with the second relay, a third relay for controlling whether to bypass a DC loop forming circuit, and a facsimile apparatus with a telephone And a fourth relay for controlling a ring signal to be transmitted to a terminal, such as a modem, without using a configuration having a monitor device outside the modem device, which has conventionally been a problem. It has the effect of monitoring.

(Embodiment 1) FIG. 1 shows an embodiment of the configuration of a modem apparatus according to the present invention. In FIG. 1, a modem 11 modulates and demodulates digital data into analog signals for transmission over a public telephone line. In recent years, its main circuit has been integrated into an IC. Reference numeral 12 denotes a terminal connected to the modem, such as a general public telephone line or a facsimile apparatus with a telephone, for exchanging data with the modem 11. The insulating transformer 13 has the function of transforming the difference between the voltage level on the modem 11 side and the voltage level on the telephone line side. The resistor 14 has the function of adjusting the signal level, and the capacitor 1
Reference numeral 5 has a function of blocking a DC signal. Relay 16
Has the function of turning on and off the connection between the modem 11 and the terminal 12 such as a telephone line or a facsimile machine with a telephone.

Next, the operation of the embodiment configured as described above will be described. When the relay 16 is on, the terminal 1 such as a telephone line or a facsimile machine with a telephone
2 is transmitted to the modem 11 via the isolation transformer. Conversely, a signal from the modem 11 is also transmitted to a terminal 12 such as a telephone line or a facsimile machine with a telephone. On the other hand, when the relay 16 is off, a signal from the terminal 12 such as a telephone line or a facsimile machine with a telephone is not transmitted to the modem 11 via the relay 16, and conversely, a signal from the modem 11 is also transmitted to the telephone line or the telephone. Is not transmitted via the relay 16 to the terminal 12 such as a facsimile machine. However, since the resistor 14 and the capacitor 15 are provided in parallel with the relay 16, the AC signal can be transmitted to both. That is, for example, when making a telephone call, the exchange of both voice signals starts from the moment when one telephone calls the other telephone and picks up the handset. Therefore, unless both so-called off-hook relays are in the on state, the state of the other party cannot be known. However, this is possible if the configuration of the modem device according to the present invention is adopted. That is, even when the relay 16 is in the off state, the state of the other party can be monitored from the circuit side of the resistor 14 and the capacitor 15 in an AC manner. Moreover, it is possible to sufficiently cope with the signal processing inside the modem without the need to separately add a monitor device to the outside as in the prior art.

(Embodiment 2) FIG. 2 shows an embodiment of the configuration of a modem device according to the present invention. In FIG. 2, a modem 21 modulates and demodulates digital data into analog signals for transmission over a public telephone line. In recent years, its main circuit has been integrated into an IC. Reference numeral 22 denotes a terminal connected to the modem, such as a general public telephone line or a facsimile machine with a telephone, for exchanging data with the modem 21. The insulating transformer 23 has the function of transforming the difference between the voltage level on the modem 21 side and the voltage level on the telephone line side. The resistor 24 has a function of adjusting the signal level.
Reference numeral 5 has a function of blocking a DC signal. Relay 26
Has the function of turning on and off the connection between the modem 21 and the terminal 22 such as a telephone line or a facsimile machine with a telephone. The signal detecting and processing means 27 provided in the modem is an AC signal from a terminal 22 such as a telephone line or a facsimile machine with a telephone, for example, a CNG signal in a facsimile or a DTMF signal of a telephone.
And * signals are detected, thereby transmitting passwords and other messages and monitoring the status of the other party.

Next, the operation of the embodiment configured as described above will be described. When the relay 26 is on, the terminal 2 such as a telephone line or a facsimile machine with a telephone
2 is transmitted to the modem 21 via the isolation transformer. Conversely, a signal from the modem 21 is also transmitted to a terminal 22 such as a telephone line or a facsimile machine with a telephone. On the other hand, when the relay 26 is off, a signal from the terminal 22 such as a telephone line or a facsimile machine with a telephone is not transmitted to the modem 21 via the relay 26, and conversely, a signal from the modem 21 is not transmitted to the modem 21 via the relay 26. It is not transmitted to the terminal 22 such as a line or a facsimile machine with a telephone. However, since the resistor 24 and the capacitor 25 are provided in parallel with the relay 26, the AC signal can be transmitted to both.

That is, for example, when making a telephone call, the exchange of both voice signals starts from the moment when one telephone calls the other telephone and picks up the handset. Therefore, unless both so-called off-hook relays are in the on state, the state of the other party cannot be known.
However, this is possible if the configuration of the modem device according to the present invention is adopted. That is, even when the relay 26 is off, it is possible to monitor the state of the other party in an AC manner through the series circuit of the resistor 24 and the capacitor 25.
Moreover, it is possible to sufficiently cope with the signal processing inside the modem without the need to separately add a monitor device to the outside as in the prior art. Also, an AC signal from a terminal 22 such as a telephone line or a facsimile machine with a telephone, for example, a CNG signal in a facsimile or a DTM of a telephone
By detecting the # and * signals as F signals, it becomes possible to transmit a password and other messages and to monitor the state of the other party.

(Embodiment 3) FIG. 3 shows an embodiment of the configuration of a modem device according to the present invention. In FIG. 3, a modem 31 modulates and demodulates digital data into analog signals in order to transmit digital data over a public telephone line. In recent years, its main circuit has been integrated into an IC. Reference numeral 32 denotes a general public telephone line connected to the modem, which exchanges data with the modem 31. The insulating transformer 33 has the function of transforming the difference between the voltage level on the modem 31 side and the voltage level on the telephone line side. The resistor 34 has a function of adjusting a signal level, and the capacitor 35 has a function of blocking a DC signal. First
The relay 41 has an operation of selecting the telephone line 32 or the DC power supply 47 to be connected to the terminal 45 such as a facsimile machine with a telephone or the modem 31, and the second relay 42 has the function of connecting the modem 31 and the telephone line 32. The third relay 43 has an operation of controlling whether to bypass a diode bridge 46 and a DC circuit 47 provided for forming a DC loop, and the fourth relay 44 has an operation of controlling the connection. Ring signal generation circuit 4
8 has the effect of controlling whether or not to transmit the ring signal created in step 8 to a terminal 45 such as a facsimile machine with a telephone. The ring signal generating circuit 48 has a function of generating a signal similar to a ring signal transmitted through a normal public telephone line, and the generated ring signal is transmitted to the telephone. That is, a ring signal can be transmitted from the modem 31 to the terminal 45 such as a facsimile machine with a telephone, that is, a call can be made.

Next, the operation of the embodiment configured as described above will be described. First, when transmission is performed between the telephone line 32 and the modem 31, the first relay 41 is turned off (the upper side in FIG. 3; the upper side is turned off and the lower side is turned on in all relays hereinafter); 42 is on, the third relay 43 is off, and the fourth relay 44 is off. In this state, a DC loop is formed in the line,
The modem 31 is connected to a telephone line 32 via an insulating transformer 33, and normal transmission is performed.

Next, in the conventional configuration, when transmission is performed between a terminal 45 such as a facsimile machine with a telephone and the modem 31, the first relay 41 is turned on, the second relay 42 is turned off, and the third relay 42 is turned off. Is turned off (there is no equivalent in the conventional configuration because the present relay does not exist), and the fourth relay is turned off. In this state, since no DC voltage is applied to the diode bridge 46, the diode is off, and the signal between the terminal 45 such as a facsimile machine with a telephone and the modem 31 and the modem 31 has a reduced level. Reliable communication becomes impossible. Then, the second relay 42 may be turned on and the diode bridge 46 may be turned on. In this case, the DC power supply 49 supplies current to both the terminal 45 such as a facsimile apparatus with a telephone and the DC circuit 47. A power supply is required, and a large-capacity and expensive power supply is required. Therefore, in this embodiment, the third relay 43 is provided, and by turning on the third relay 43, the diode bridge 46 and the DC circuit 47 are bypassed, so that communication between the terminal 45 such as a facsimile machine with a telephone and the modem 31 is enabled. Is what you do.

Further, according to the present embodiment, when the terminal 45 such as a facsimile apparatus with a telephone communicates with another terminal via the telephone line 32, and when the monitoring of the line signal is necessary, the above-mentioned operation is performed. Similarly, by turning off the second relay 42 and turning on the third relay 43, the diode bridge 46 and the DC circuit 47 are bypassed. As a result, the line signal can be monitored without a voltage drop by the diode.

[0019]

As described above, according to the present invention, it is possible to monitor a telephone line or a telephone with a simple circuit configuration without the need to separately add a monitoring device to the outside as in the conventional configuration. Is obtained.

[Brief description of the drawings]

FIG. 1 is a diagram showing a modem device according to an embodiment of the present invention;

FIG. 2 is a diagram showing a modem device according to an embodiment of the present invention;

FIG. 3 is a diagram showing a modem device according to an embodiment of the present invention;

FIG. 4 is a diagram showing a conventional modem device.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 11 Modem 12 Terminal such as facsimile apparatus with telephone line or telephone 13 Insulation transformer 14 Resistance 15 Capacitor 16 Relay 21 Modem 22 Terminal such as facsimile apparatus with telephone line or telephone 23 Insulation transformer 24 Resistance 25 Capacitor 26 Relay 27 Signal detection and Processing means 31 Modem 32 Telephone line 33 Insulation transformer 34 Resistance 35 Capacitor 41 First relay 42 Second relay 43 Third relay 44 Fourth relay 45 Terminal such as facsimile machine with telephone 46 Diode bridge 47 DC circuit 48 Ring signal generation circuit 49 DC power supply

Claims (3)

[Claims] 1. A circuit in which a capacitor and a resistor are connected in series between a terminal such as a telephone line or a facsimile machine with a telephone and an insulating transformer, and a relay is connected in parallel with the series-connected capacitor and resistor. A modem device. 2. A circuit in which a capacitor and a resistor are connected in series between a terminal such as a telephone line or a facsimile machine with a telephone and an insulating transformer, and a relay is connected in parallel with the series-connected capacitor and resistor. A modem device having means for detecting and processing a certain signal in the modem. 3. A first relay for selecting a telephone line or a DC power supply to be connected to a terminal or a modem such as a facsimile apparatus with a telephone, and a second relay for controlling connection between the modem and the telephone line. A circuit in which a capacitor and a resistor are connected in series with the second relay, and a third relay that controls whether to bypass the DC loop forming circuit,
And a fourth relay for controlling a ring signal to be transmitted to a terminal such as a facsimile apparatus with a telephone.