JPH0761102B2 - In-band signaling device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an in-band signal device that uses a frequency within a voice band as a signal.

[Conventional technology]

When performing a dial pulse transmission test, a level dial confirmation test, and the like in this type of in-band signal device, it is necessary to return the signal. When a station is equipped with this in-band signaling device, for example, when performing these tests, it is necessary to operate both stations facing each other, and two operators must perform the operations.

Meanwhile, in order to perform an efficient test, some in-band signal devices have a function of returning a signal during the above-described test. Such an in-band signal device diverts the frequency of the signal current in the voice band when folding back.

[Problems to be Solved by the Invention]

The above-described conventional in-band signaling device, for example, an in-band signaling device without a loopback function, requires a loopback operation on the receiving side, and therefore cannot be efficiently tested. Further, in the in-band signal device to which a folding function is added in part, there is folding on the receiving side, but level equalization does not occur. Even if there is a level equalization function, it is not clear whether it is the return on the transmission path side or the return on the terminal side. That is, in this in-band signal device, it is not possible to determine whether the device or the terminal is defective because the signal is returned inside the opposite station. Further, since the frequency for the signal current is diverted, it causes a wrong connection and a hold with respect to the PBX (Private Branch Converter), and for terminals, there is a disadvantage that a temporary bell is activated.

It is an object of the present invention to eliminate such drawbacks and to provide an in-band signal device capable of returning a signal by remote control at the time of a test or the like.

[Means for Solving the Problems]

To achieve the above object, the present invention connects a first input terminal to one input terminal of a transmission circuit via one contact of a first switch circuit, and connects a second input terminal to a first coupling. The other input terminal of the transmission circuit through one contact of the circuit and the second switch circuit, the oscillation circuit is connected to the other input terminal of the transmission circuit through the first setting circuit, and the transmission circuit Of the receiving circuit is connected to LINE-S, the input terminal of the receiving circuit is connected to LINE-R, and one output terminal of the receiving circuit is connected to the first output terminal through one contact of the third switch circuit. The second output terminal of the receiving circuit is connected to the second output terminal of the fourth switching circuit via one contact of the fourth switching circuit and the second coupling circuit.
The other contact of the first switch circuit is connected to the other contact of the third switch circuit, and the other contact of the second switch circuit is connected to the other of the fourth switch circuit via the folding circuit. It is configured by connecting to the contact and connecting the detection circuit in series with the bandpass filter, the amplifier, and the rectifier in this order. The input end of the detection circuit, which is the input end of the bandpass filter, is connected to LINE-R. Then, the output end of the detection circuit, which is the output end of the rectifier, is connected to one input end of the comparator via the first resistor, and the capacitor is connected between one input end of the comparator and ground. A reference voltage is applied between the other input end of the comparator and the ground, a light emitting diode is connected to the output end of the comparator via the second resistor, and the output voltage of the comparator is set to the first output via the second setting circuit.
Switch circuit, second switch circuit, third switch circuit,
And the fourth switch circuit.

〔Example〕

Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing an embodiment of the present invention.
The in-band signaling device of this embodiment is provided in each of the master station and the slave station connected via the transmission line. Since the respective in-band signal devices have the same configuration, the in-band signal device provided in the master station will be described.

This in-band signal device includes an oscillation circuit 1 and setting circuits 2 and 13.
A transmission circuit 3, a reception circuit 4, a detection circuit 5 including a bandpass filter 5A, an amplifier 5B and a rectifier 5C, a capacitor 6, resistors 7 to 10, a comparator 11, and a light emitting diode 12. , Switch circuits 14 to 17, folding circuit 18,
It is composed of coupling circuits 20 and 21.

In the in-band signal device having such a configuration, the oscillation circuit 1
Oscillates a folding signal having a frequency different from the signal current input from another device. This return signal is used when the signal is returned at the slave station when a dial pulse transmission test or the like is performed.

The setting circuits 2 and 13 include setting switches 2A and 13A, respectively. “Open” and “Close” of these setting switches 2A and 13A are
It is determined when the in-band signaling device of this embodiment is installed. Then, the setting switch 2A of the setting circuit 2 of the in-band signaling device installed in the master station is in the "closed" state,
The setting switch 13A of the setting circuit 13 is in the "open" state. In addition, the setting circuit of the in-band signaling device installed in the slave station
The setting switch 22A of 22 is in the "open" state, and the setting switch 33A of the setting circuit 33 is in the "closed" state.

The transmitter circuit 3 does not include input terminals 3A and 3B and an output terminal 3C. The signal input to the input terminal SS is input to the input terminal 3A of the transmission circuit 3 via the switch circuit 17, and the signal input to the input terminal 4WS is input to the input terminal 3B. Input via 16 and. Further, the oscillation circuit 1 is connected to the input terminal 3B via the setting circuit 2. The output terminal 3C of the transmission circuit 3 is connected to the output terminal LINE-S.

The receiving circuit 4 includes an input terminal 4A and output terminals 4B and 4C. The input terminal 4A of the receiving circuit 4 is the input terminal LINE-R
Connected with. The signal output from the output terminal 4B of the receiving circuit 4 is sent to the output terminal 4WR via the switch circuit 15 and the coupling circuit 21. The signal output from the output terminal 4C is sent to the output terminal SR via the switch circuit 14.

The detection circuit 5 includes a bandpass filter 5A, an amplifier 5B, and a rectifier 5C. The bandpass filter 5A has an input terminal
The signal that is input to LINE-R and branched into two is input.
Then, the band-pass filter 5A passes the above-mentioned folded signal from the input signals. The rectifier 5C rectifies the folded signal input via the amplifier 5B and converts it into a DC signal. In this way, the detection circuit 5 extracts the return signal and converts it into a DC signal.

The comparator 11 compares the voltage generated by the resistors 8 and 9 with the input signal. Then, the comparison circuit 5
When the DC folding signal output from the rectifier 5C and corrected in waveform by the capacitor 6 is input, the comparator
11 inverts the output voltage. The resistor 7 connected to the comparator 11 is for impedance matching.

The light emitting diode 12 emits light by the current flowing through the resistor 10 when the detection circuit 5 is extracting the return signal, that is, when the output voltage of the comparator 11 is inverted.

The switch circuits 14 to 17 include switches 14A to 17A, respectively. These switches 14A to 17A are the comparator 11
Is controlled by the output voltage of the input terminal 3 of the transmitter circuit 3.
The connections of A, 3B and the output terminals 4B, 4C of the receiving circuit 4 are switched.

Next, examples of the present invention will be described.

Normally, the signal from the master station input terminal SS is
Is sent to the input terminal 3A of the transmission circuit 3 via the switch 17A of the transmission circuit 3 and the signal from the input terminal 4WS passes through the coupling circuit 20 and the switch 16A of the switch circuit 16 to the input terminal 3B of the transmission circuit 3. Sent to. The signal output from the output terminal 3C of the transmission circuit 3 is sent to the output terminal LINE-S of the master station.
This signal goes through the transmission path and is input to the slave station LINE-R
Sent to.

The signal from the input terminal LINE-R of the slave station is branched and output to the reception circuit 24 and the detection circuit 25. Input terminal LINE-R
Since the signal from 1 does not include the return signal, the detection circuit 25 does not extract the return signal, and the comparator 31 does not invert the output voltage. Therefore, the switch circuits 34 to 37
Cannot be switched with the switches 34A to 37A.

In this state, the signal from the output terminal 24C of the receiver circuit 24 is sent to the output terminal SR via the switch 34A of the switch circuit 34, and the signal from the output terminal 24B of the receiver circuit 24 is switched to the switch circuit. It is sent to the output terminal 4WR via the switch 35A of 35 and the coupling circuit 41.

Similarly, the signals input to the input terminals 4WS and SS of the slave station are sent to the output terminal LINE-S. This signal is sent to the input terminal LINE-R of the master station via the transmission path and output from the output terminals 4WR and SS of the master station.

Next, in order to perform a dial pulse transmission test or the like, the signal may be returned at the slave station. In such a case, the return signal from the oscillation circuit 1 in the master station is sent to the input terminal 3B of the transmission circuit 3 via the switch 2A of the setting circuit 2. This return signal is output from the output terminal 3C of the transmission circuit 3 and sent to the output terminal LINE-S of the master station. The return signal is sent via the transmission line to the input terminal LINE− of the slave station.
Sent to R.

The return signal from the input terminal LINE-R of the slave station is input to the bandpass filter 25A of the detection circuit 25. Bandpass filter 25A passes the folded signal and sends this signal to amplifier 25B. The folded signal input to the rectifier 25C via the amplifier 25 is rectified and converted into a DC folded signal. This DC folding signal is transmitted to the capacitor 26
The waveform is corrected by and is input to the comparator 31.
The comparator 31 inverts the output voltage by this DC folding signal. Due to the inverted output voltage of the comparator 31, a current flows through the resistor 30 and the light emitting diode 32 emits light. This shows that the return signal is being extracted at the slave station. At the same time, the inverted output voltage of the comparator 31 is sent to the switch circuits 34 to 37 via the switch 33A of the setting circuit 33. The switch circuits 34 to 37, by the inverted output voltage,
Switch the switches 34A to 37A. By this switching,
The output terminal 24C of the receiving circuit 24 is connected to the switch 34A of the switch circuit 34, the return line 39, and the switch 3 of the switch circuit 37.
It is connected to the input terminal 23A of the transmission circuit 23 via 7A and. Then, the output terminal 24B of the reception circuit 24 is connected to the input terminal 23B of the transmission circuit 23 via the switch 35A of the switch circuit 35, the folding circuit 38, and the switch 36A of the switch circuit 36.

In this way, according to the present embodiment, the return signal is transmitted from the transmission side which is the master station, and the signal is automatically returned at the reception side which is the slave station, so only the transmission side need be operated during the test. It is possible to save labor and perform efficient tests. In addition, since this embodiment is composed of a simple circuit, it is easy to manufacture, has a small number of parts, and is economical. Further, in this embodiment, since the signal is returned at the slave station, it is possible to judge whether the device installed in the slave station has a malfunction or the terminal has a malfunction.

〔The invention's effect〕

As described above, the present invention has an effect that the signal output from the receiving unit on the receiving side can be automatically returned to the transmitting unit by transmitting the returning signal on the transmitting side.

[Brief description of drawings]

 FIG. 1 is a block diagram showing an embodiment of the present invention. 1,21 …… Oscillation circuit 2,13,22,33 …… Setting circuit 3,23 …… Transmission circuit 4,24 …… Reception circuit 5,25 …… Detection circuit 5A, 25A …… Bandpass filter 5B , 25B …… Amplifier 5C, 25C …… Rectifier 6,26 …… Capacitor 7 ～ 10,27 ～ 30 …… Resistance 11,31 …… Comparator 12,32 …… Light emitting diode 14 ～ 17,34 ～ 37 …… Switch Circuit 18,38 …… Folding circuit 19,39 …… Folding line 20,21,40,41 …… Coupling circuit

Claims (1)

[Claims] 1. A first input terminal is connected to one input terminal of a transmission circuit through one contact of a first switch circuit,
The second input terminal is connected to the other input terminal of the transmission circuit via one contact of the first coupling circuit and the second switch circuit, and the oscillation circuit is connected to the other input terminal of the transmission circuit via the first setting circuit. Connect to the input terminal of the and connect the output terminal of the transmitter circuit to LINE-S
, The input terminal of the receiving circuit is connected to LINE-R, one output terminal of the receiving circuit is connected to the first output terminal via one contact of the third switch circuit, and the other of the receiving circuit is connected. The output terminal of the second switch circuit to one contact of the fourth switch circuit and the second
The second contact is connected to the second output terminal through the coupling circuit, the other contact of the first switch circuit is connected to the other contact of the third switch circuit, and the other contact of the second switch circuit is connected through the folding circuit. , Connected to the other contact of the fourth switch circuit,
The detection circuit consists of a band-pass filter, an amplifier, and a rectifier, which are cascaded in this order. The input end of the detection circuit, which is the input end of the band-pass filter, is connected to LINE-R, and the output of the rectifier is connected. The output end of the detection circuit, which is the end, is connected to one input end of the comparator via the first resistor, the capacitor is connected between one input end of the comparator and the ground, and the other input end of the comparator is connected. A reference voltage is applied between the comparator and the ground, a light emitting diode is connected to the output end of the comparator via a second resistor, and the output voltage of the comparator is connected to the first switch circuit and the second switch via the second setting circuit. An in-band signal device characterized by being added to a circuit, a third switch circuit, and a fourth switch circuit.