JPH0714178B2 - Off-talk communication Home connection device tester - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention realizes operations among an information providing center, an intra-office connection device, and a home connection device that constitute off-talk communication, and has a home connection device. The present invention relates to a device for testing the function of off-talk communication in progress.

[Prior Art] Off-talk communication refers to a telecommunications service that broadcasts voice information from an information center to a subscriber's house by using the idle time of a telephone line.

The off-talk communication system is shown in FIG. In the office of the telephone station 10, an intra-station connecting device 12 is inserted between the telephone line 13 and the exchange 11, and the intra-station connecting device 12 and the center device 21 of the information providing center 20 are connected via a center line 22. On the other hand, in the user's house 30, the telephone line 13 and the output device 31 such as a speaker are connected via the in-home connecting device 32. Normally, when the user's telephone 33 is not used, that is, when the telephone line 13 is idle, information such as music played from the center device 21 is passed to the telephone line 13 via the intra-station connection device 12, It is output from the output device 31 at the home 30 via the in-home connection device 32. When a call is made from the telephone 33 or an incoming call is made to the telephone 33, the intra-office connection device 12 disconnects the telephone line 13 and the sensor line 22 and prioritizes the telephone call from the telephone 33. When the call ends, the intra-office connection device 12 reconnects the center line 22 and the telephone line 13. The in-home connection device 32 also has a call priority function, and disconnects the connection between the telephone line 13 and the output device 31 during a call to prevent the call voice from being output from the output device 31.

The information provided from the center device 21 to the user's home 30 is not a single channel but a plurality of channels. The selection is made by a channel switching signal sent from the in-home connecting device 32 to the center device 21, and when the in-station connecting device 12 detects the signal, it switches the center line 22 to connect to another channel.

[Problems to be Solved by the Invention]

In such a conventional device, in order to confirm the call priority function and the channel switching signal detection function of the home connection device 32, as shown in FIG. 3, an off-talk home connection device tester (hereinafter simply referred to as a tester) is used. 40) is inserted between the home connection device 32 and the telephone line 13. The signal used for the channel switching signal is the telephone line 13
It was created by short-circuiting for a certain time with a high resistance of KΩ.
The conventional tester 40 confirms the transmission of the channel switching signal by detecting the voltage change due to this short circuit.It supplies the voltages of −48V and 0V as with the telephone line 13, and the reference potential point is the telephone line. In order to make it equal to 13, there was a drawback that the detection operation would not occur unless the earth was grounded.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a tester that does not require grounding.

[Means for Solving the Problems]

The off-talk communication home connection device tester according to the present invention includes a signal input unit for inputting information corresponding to a plurality of channels, and a first signal switching for selecting a plurality of channels of the signal input unit connected to the signal input unit. Means, an in-home connection device, a second signal switching means for connecting and disconnecting the telephone line and the first signal switching means, and a telephone line and a telephone line connected from the exchange through the first photocoupler. To an incoming call detection circuit that detects an incoming call signal transmitted to the second signal switching means and disconnects the second signal switching means, and is connected to the telephone line from the telephone via the second photocoupler to the telephone line through the home connection device. A transmission detection circuit that detects the transmission signal to be sent and puts the second signal switching means into the disconnection state, the first signal switching means and the second signal switching means, and the third fo Are connected via a coupler, it is obtained by including a channel switching signal detecting circuit for switching the selected channel of the first signal switching means detecting a channel switch signal from the home connection device.

[Action]

In this invention, the incoming call detection circuit, the outgoing call detection circuit, the channel switching signal detection circuit, etc. are all connected to the telephone line.
Since it is connected via the 1st, 2nd, and 3rd photocouplers, it operates normally even if there is no earth ground on the tester side.

〔Example〕

 Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram of an embodiment of the present invention. 40A is an off-talk communication home connection device tester of the present invention (hereinafter simply referred to as a tester), 41 is a signal input section, 42 is a polarity switching circuit of the telephone line 13, 43 is an incoming detection circuit, and 44 is an outgoing detection circuit. , 45 is a cut relay serving as second signal switching means, 46 is a channel switching signal detection circuit, 47 is a channel switching circuit serving as first signal switching means, 48 is an emergency notification circuit, and 49 is an end signal circuit. Others are second
This is the same as in FIGS. Also, PC1 to PC3 are first to third
Is a photocoupler, D is a diode, R is a resistor,
C is a capacitor, RL1 is a relay, r1 and r2 are contacts of this relay RL, RL2 is a relay, r2 is its contact, AND is an AND gate, COM is a comparator, and DEL is a delay circuit. Is added to the subscript.

The telephone line 13 and the home connection device 32 are connected to the tester 40A, and a signal such as voice is input to the signal input unit 41.

When the telephone 33 is in a call state, that is, when the telephone line 13 is in use, a potential of −48V is applied to the line L1 of the telephone line 13 and a potential of 0V is applied to the line L2. In the incoming call detection circuit 43, the DC component is cut by the capacitor C1, so the incoming call detection circuit
No current flows through the first photocoupler PC1 for detecting the AC signal 43. Therefore, the photocoupler PC1 does not operate, and the voltage V1 applied to the resistor R3 is divided by the resistor R3 and then input to one input terminal of the AND gate AND. Further, in the transmission detection circuit 44, the home connection device 32 side is in an electrically open state, and since no current flows in the second photocoupler PC2 for detecting an AC signal, the photocoupler PC2 does not operate and the resistor The voltage V2 applied to R4 is divided by the resistor R4 and input to the other input terminal of the AND gate AND. Therefore, since both inputs of AND gate AND are high level, the output also becomes high level,
The relay RL1 is operated to bring the cut relay 45 into the connected state, and the signal input unit 41, the home connection device 32 and the telephone line 13 are connected. In this state, if information such as voice is sent from any channel of the signal input unit 41, it is output to the output device 31 such as a speaker via the in-home connection device 32, and the off-talk communication function can be confirmed.

When there is an incoming call, a 16 Hz signal is sent from the exchange 11 to the telephone line 13. Since the capacitor C1 of the incoming call detection circuit 43 is an AC signal, it passes this 16Hz signal, and the photocoupler PC
1 works. Therefore, the voltage V applied to the resistor R 3
Since 1 flows into the ground through the resistor 3 and the photocoupler PC1, the input to the AND gate AND becomes low level, and the output of the AND gate AND also becomes low level. Therefore, the operation of the relay RL1 is restored and the cut relay 45 is in the disconnected state. Further, when a call is made from the telephone 33, the telephone line 13 is short-circuited, so a current flows into the photocoupler PC2 of the transmission detection circuit 44 to activate the photocoupler PC2, and the voltage V2 applied to the resistor R4 becomes a resistance. Since the current flows into the ground through the device R4 and the photocoupler PC2,
The input to the AND gate AND becomes low level, and the output of the AND gate AND also becomes low level. Therefore, the operation of the relay RL1 is restored and the cut relay 45 is in the disconnected state. In this way, when the telephone line 13 is in a call state, the signal input unit 41 is disconnected from the home connection device 32 and the telephone line 13. In this state, even if information such as voice is flown from any channel of the signal input unit 41, it is not output to the output device 31 such as a speaker.

The channel switching signal from the in-home connection device 32 is generated by short-circuiting the telephone line 13 with a high resistance of 16 KΩ for about 250 milliseconds. The third photocoupler PC3 of the channel switching signal detection circuit 46 is off at a normal voltage depending on the value of the resistor R7, and is preset to operate when the 16KΩ resistor is connected in parallel in the circuit. . Therefore, when the channel switching signal is detected, the photocoupler PC3 operates and the voltage V3 applied to the resistor R6 flows into the ground through the resistor R6, so that a low level is input to the comparator circuit COM. The low level to the comparator circuit COM is divided into two, one is OP
Input to the positive terminal of the amplifier, and the other input to the capacitor C4 at the negative terminal via the diode D2 for preventing backflow to the positive terminal. The capacitor C4 discharges the electric charge stored beforehand by the low level input to the minus terminal of the OP amplifier, so the OP amplifier compares the magnitude with the signal input to the plus terminal and outputs the high level from its output terminal. Send out. The high level sent from the OP amplifier is relayed through the delay circuit to the relay RL of the channel switching circuit 47.
Operate 2 As a result, the two inputs C of the signal input section 41
By inputting different information to H1 and CH2, the output device 31 can confirm the channel switching. There is a possibility that the photocoupler PC3 may malfunction due to the potential drop for a short time of about several tens of milliseconds from the time when the telephone 33 makes a call until the cut release 45 operates. The delay circuit DEL is for removing this signal and allowing the channel switching signal to pass, and is an integrator circuit that combines a resistor and a capacitor, thereby preventing malfunction.

The emergency call circuit 48 is for operating the emergency call circuit inside the home-connection device 32. For example, the pushbutton dial signals of the telephone set 33, which correspond to "#" and "*", are transmitted by 4H.
Repeated alternately in the cycle of z. Similarly, in order to release the emergency call circuit 48, for example, signals corresponding to "C" and "D" are set to 4Hz.
The signals are sent alternately in a cycle. The termination signal circuit is the home connection device 32
For example, a sine wave with a frequency of 600 Hz is sent at a level of -15 dBm to operate the communication end detection circuit of the home connection device 32, and along with this, the speaker output ON / OFF circuit inside the home connection device 32 operates. To do.

〔The invention's effect〕

As described above, the present invention provides a signal input section for inputting information corresponding to a plurality of channels, a first signal switching unit connected to the signal input section for selecting a plurality of channels of the signal input section, and a home A second switching means for connecting and disconnecting the connection device and the telephone line and the first signal switching means, and an incoming call which is connected to the telephone line via the first photocoupler and is sent from the exchange to the telephone line. An incoming signal detection circuit that detects a signal and turns off the second signal switching means, and an outgoing signal that is connected to the telephone line via the second photocoupler and is sent from the telephone to the telephone line via the home connection device. Is connected to the first signal switching means and the second signal switching means through a third photo coupler, Since a channel switching signal detection circuit for detecting a channel switching signal from the internal connection device and switching the selected channel of the first signal switching means is provided, grounding is indispensable in the conventional device, but in the present invention, the photo coupler is used. Since it is used, there is an advantage that it is not necessary and is not restricted in use. Further, since the tester of the present invention is equipped with all the functions on the side of the center device, there is an advantage that this one can test each function possessed by the off-talk communication home connection device.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of a tester of the present invention and a connection state with a telephone line and a home connection device, and FIGS. 2 and 3 are configuration diagrams of a conventional off-talk communication system. In the figure, 10 is a telephone station, 13 is a telephone line, 30 is a user's house, 31 is an output device, 32 is a home connection device, 33 is a telephone, 40A is a tester, 41 is a signal input section, and 42 is a polarity switching circuit. , 43 is an incoming call detection circuit, 44 is an outgoing call detection circuit, 45 is a cut relay, 46 is a channel switching signal detection circuit, 47 is a channel switching circuit, 48 is an emergency notification circuit, 49 is an end signal circuit, and PC1 is the first photo. Coupler, PC2 is the second photo coupler, PC3
Is the third photocoupler.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Kenji Ito 1-6, Uchisaiwaicho, Chiyoda-ku, Tokyo Nihon Telegraph and Telephone Corporation (72) Inventor Atsushi Kondo 1-6, Uchisaiwaicho, Chiyoda-ku, Tokyo Nihon Telegraph and Telephone Corporation (56) References

Claims (1)

[Claims] 1. A function of the in-home connecting device is inserted between an off-talk in-home connecting device for transmitting information sent to the telephone line to an output device when the telephone line is not in use and the telephone line. In an off-talk communication home connection device tester to be tested, a signal input section for inputting information corresponding to a plurality of channels, and a first signal switching means connected to the signal input section for selecting a plurality of channels of the signal input section. A second signal switching means for connecting and disconnecting the home connection device and the telephone line to and from the first signal switching means, and a telephone line and a first photocoupler, which are connected to each other through an exchange. An incoming call detection circuit that detects an incoming call signal sent to a telephone line and puts the second signal switching means into a disconnection state, and is connected to the telephone line through a second photocoupler. A call detection circuit that detects a call signal sent from the telephone to the telephone line through the home connection device and puts the second signal switching means into a disconnection state; the first signal switching means; A channel switching signal detection circuit which is connected to the second signal switching means via a third photo coupler, detects the channel switching means from the home connection device, and switches the selected channel of the first signal switching means. An off-talk communication in-home connection device tester characterized by the above.