JPH10164207A - Check device for telephone line - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a check device for a telephone line by which the telephone line is checked without giving effect on the telephone line in use and which copes with all checks. SOLUTION: The check device is provided with a probe 1 in contact with a conductor part of a telephone line, a resistor 2 that is connected to the probe 1 and whose resistance is sufficiently higher than that of a subscriber terminal, an amplifier circuit 3 that amplifies a voltage detected by the resistor 2, a hearing circuit 5 to drive an earphone 4 by the amplified signal, and a polarity display circuit 6 that displays the polarity of the conductor part based on the level of the voltage of the amplified signal.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a telephone line,
The present invention relates to an inspection device that performs an inspection such as a telephone call, a type determination,
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a telephone line inspection apparatus capable of performing inspection without affecting a line in use and capable of handling all inspections with one unit.

[0002]

2. Description of the Related Art In telephone construction, a worker needs to perform a confirmation operation such as a polarity check, a busy check, and a type check on a telephone line to be constructed. The reason is described below.

A direct current is applied to a telephone line, while some user equipments (subscriber terminals) such as telephones break down when the polarity is reversed. In addition, the protector installed at the separation point between the outside line and the house has a built-in device that can perform a return test in order to quickly respond to a failure, and the return circuit is configured by reversing the polarity. It is supposed to be. Therefore, in order to maintain the subscriber terminal normally and satisfy the loopback function of the protector, the polarity must be correctly connected. As shown in FIG. 4, construction sites requiring such confirmation of the polarity include an MDF (distribution panel for connecting the exchange and an outside line) 42 in a telephone exchange 41 or a subscriber's house, and a wiring cable 43. Terminal box 44 for branch wiring from the terminal to the subscriber's house, protector 45 installed at the demarcation point between the outside line and the house, house line 46
And a rosette 48 for connecting the terminal 47 and the like. Therefore, when a new terminal 47 or a security device 45 is to be installed, or when the terminal 47 at the subscriber's house is to be relocated, external structures (cables 43, drop-in wires, connection terminal boxes 44) are to be constructed or subscribed. When renewing or changing for the convenience of the user, the polarity is checked when the line accommodated in the exchange 41 or the MDF 42 at the user's house is replaced with another terminal due to the extension of the cable 43 or the construction in the office. Will be done. If the line to which the terminal 47 has already been attached is connected properly, there is no need to check the polarity. However, if construction is performed at a point other than the point where this terminal is attached, the polarity is incorrectly inverted. To connect.
It is necessary to confirm the polarity at the connection point between the terminal 47 and the rosette 48. In FIG. 4, locations requiring confirmation of the polarity are indicated by crosses.

[0004] When constructing an existing telephone line, if the telephone line happens to be started when it is busy, line failures such as line disconnection and crosstalk will be caused. In addition, since the construction of data lines such as dedicated lines is performed in advance by borrowing the lines, there is no problem of line disconnection during talking, but if the user accidentally contacts the fax line or data line used by the user, the system This causes a down, an error, or an image drop. Since these things cause great annoyance to the user, the person in charge of the construction needs to work carefully. However, the line type is not displayed even when various lines are collectively accommodated in the MDF, the connection terminal box, the protector, and the like of the exchange office. Further, even in the case of the MDF at the user's house, if many protectors are installed, it is not known which protector accommodates which line. In the middle part of the equipment, such as cables and terminal boards, it is not possible to determine which line accommodates which subscriber. Therefore, before constructing a telephone line, an inspection is performed to confirm whether the telephone line is busy. At that time, general line, fax line,
Also check the type of data line.

[0005] As described above, during telephone construction, inspections such as polarity confirmation, busy confirmation, type confirmation, and the like are required.

FIG. 5 shows an example of the MDF. This MDF5
1 has a terminal plate 51a for accommodating 6000 pairs of terminals on the exchange 52 side, while areas A, B, C, and D on the outside line side are provided.
Separately 3000 pairs, 2400 pairs, 1800 pairs, 2
There is a terminal plate 51b that accommodates 400 pairs of terminals, and a jumper wire 53 is wired between these terminal plates. In this way, thousands to tens of thousands of jumper wires 53 have a narrow MDF5.
Since it is within 1, when connecting, it is necessary to compare the terminal with the jumper wire. At this time, if a jumper wire is brought into contact with an incorrect terminal due to misunderstanding or misunderstanding of the terminal number, a failure occurs.

[0007] Polarity check, busy check, data check, FAX
As shown in Table 1, constructions that require confirmation include replacement of safety devices, replacement of drop-in wires, cable switching, installation of SO construction core wires, and switching of jumpers.

[0008]

[Table 1]

Cable switching refers to increasing the number of cables due to cable expansion, relocation that hinders cables, or additional equipment, or changing part of the cables. In the construction of new construction or relocation of a terminal etc., the extension of the cable core to create a telephone line from the exchange to the connection terminal box or to the user's home MDF is to extend the cable core. is there. Jumper switching means that when the user changes the core wire accommodated in another cable or another wire number because the cable has been increased or replaced due to additional cable, relocation that hinders the cable, additional equipment, etc. Switching the jumper line in the MDF or switching the jumper line in the MDF to change the cable core according to the transfer of the user.

[0010]

Conventionally, telephone line inspection apparatuses include a line test handset, a crystal earphone,
There is an ED insertion type inspection device and a lamp type busy check device.

The line test handset is composed of a transmitter and a receiver, is operated by an in-house power supply, and is used for meetings between workers. However, since there is a receiver, it is used for confirming a busy state. be able to. However, since the input impedance is small, connecting to a line in use has a great effect. Also, the polarity cannot be confirmed.

The crystal earphone is a commercially available crystal earphone, which is inserted into a line to perform a busy check. Also, by listening to the carrier sound, data confirmation and FAX confirmation can be performed. Input impedance is several K
It is on the order of Ω, and will be affected if connected to a line in use.
Polarity cannot be confirmed.

[0013] The LED insertion type inspection device is designed so that the polarity can be confirmed by inserting a light emitting diode (LED) into a line and emitting light with the power of the line. Only polarity confirmation is possible. The input impedance is on the order of a few kilohms and will be affected if connected to a line in use.

The lamp type busy checker is used only for the busy check, and the busy state of the lamp can be confirmed by the brightness of the lamp.

As described above, there is no conventional inspection apparatus capable of coping with all inspections by itself, and a trouble occurs when the apparatus comes in contact with a facsimile line or a data line, which inconveniences the user.

SUMMARY OF THE INVENTION An object of the present invention is to provide a telephone line inspection apparatus which solves the above-mentioned problems and which can be inspected without affecting the line in use, and which can handle all inspections with one unit. .

[0017]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a probe for contacting a conductor of a telephone line, and a resistor connected to the probe and having a sufficiently higher resistance than a subscriber terminal. A resistor having a value, an amplifier circuit for amplifying a voltage detected by the resistor, a listening circuit for driving an earphone with the amplified signal, and a polarity of the conductor based on the level of the voltage of the amplified signal. And a polarity display circuit for displaying.

The polarity display circuit includes: a determination circuit for determining that the polarity of the conductor portion is correct when the voltage of the amplified signal is higher than a predetermined determination voltage; and an indicator lamp circuit for displaying the determination by lighting the indicator lamp. And a buzzer circuit for displaying the determination by a buzzer sound.

[0019] A switch may be provided for switching the indicator light and the buzzer on / off.

The switch may be arranged on one side of a grip portion for supporting the probe by projecting it.

[0021]

An embodiment of the present invention will be described below in detail with reference to the accompanying drawings.

As shown in FIG. 1, a telephone line inspection apparatus according to the present invention comprises a probe 1 for contacting a conductor portion of a telephone line, and a probe 1 connected to the probe 1 for receiving a signal from a subscriber terminal. 2 having a sufficiently high resistance value, an amplifier circuit 3 for amplifying a voltage detected by the resistor, a listening circuit 5 for driving an earphone 4 with the amplified signal, and a high / low voltage of the amplified signal. And a polarity display circuit 6 for displaying the polarity of the conductor portion based on the above. When the voltage of the amplified signal is higher than a predetermined determination voltage, a polarity display circuit 6 determines that the polarity of the conductor portion is correct, an indicator lamp 8 that lights and displays the determination, and a display circuit that performs the determination. A buzzer 9 for displaying a sound. In addition, the inspection device includes a switch 10 that switches between an operation state and an operation state of an indicator light and a buzzer.

As shown in FIG. 2, the telephone line inspection apparatus of the present invention comprises a main body 21 containing a battery 13, a buzzer 9, and most of the circuit elements used as a power supply.
, A first probe 24 protruding from one end of the grip 23, and a cord 2 from the grip 23.
5 and a crystal earphone (not shown) removably connected to the earphone jack 11 of the main body 21 with an earphone cord (not shown). The main body 21 has a power switch 12 and a sound hole for the electronic buzzer 9 on the front, and a battery take-out lid 14 on the back. Further, a modular jack 15 and an earphone jack 11 are provided on the upper part of the main body 21. The grip section 23 includes a first probe 24 at one end, a modular jack 27 at the other end, and a push button 28 for operating the switch 10 and an indicator light 8 including an LED on a side surface. The first probe 24 and the second probe 26 have thin and sharp tips for contacting the positive and negative conductors of the telephone line, respectively, and have a structure that makes it easy to contact the target conductor. By coating it with a plastic material to the vicinity, the structure is such that contact with an undesired conductor portion can be avoided. The first probe 24 is provided together with a push button 28 and an indicator 8 which need to be operated and visually checked together with the grip portion 23.
The push button operation and visual observation are possible while the first probe 24 is in contact with the target conductor portion. Second
Since the probe 26 is connected to the cord 25, it can be moved freely.

FIG. 3 shows a specific circuit of the inspection apparatus. FIG.
As shown in, the first probe L1 and the second probe L2 are
It is connected to the main circuit through a modular connector CN1. Resistors R3 and R4 are inserted between the two probes as input resistors. The resistance value of the resistor R3 is 10 MΩ. The resistance value of the resistor R4 is 10 KΩ. Second probe L
2 is grounded to the reference voltage GND of the main circuit. The connection point between the resistors R3 and R4 is connected to a clamp circuit including diodes D1 and D2, and further to an amplifier circuit. The amplifier circuit includes an amplifier U1A housed in an amplifier IC (U1). The output of the amplifier circuit is connected to the listening circuit 5 and the polarity display circuit 6.

The listening circuit 5 is connected to an earphone driving amplifier circuit composed of an amplifier U1B housed in an amplifier IC (U1) and connected to a crystal earphone LS1 via a connector CN2.
Are connected. A resistor R is connected to the amplifier U1B.
12 and a filter consisting of a capacitor C8 are added,
External noise is prevented from entering the earphones.

The determination circuit 7 of the polarity display circuit 6 is composed of a comparator IC (U2) for comparing a voltage set by the variable resistor RV1 with a signal from the amplifier circuit. Indicator light 8
The light emitting diode D5 constituting the
It is connected to the main circuit via N1. As the buzzer 9, an electronic buzzer BZ1 is used. Operational amplifier I
A buffer circuit composed of inverters U3C and U3B incorporated in the logic IC (U3) is provided at the subsequent stage of C (U2). A light emitting diode driving circuit composed of the inverter U3A and a transistor Q1 are provided at the subsequent stage of this buffer circuit. An oscillation circuit including inverters U3D and U3E to be opened and closed and an electronic buzzer driving circuit including inverter U3F are provided.

The terminals on the main body side of the modular connector CN1 are vacant, the line for the first probe L1, the line for the second probe L2, the output line of the light emitting diode drive circuit,
A +4.5 V power supply line and a power supply line for a logic IC are assigned.

Each terminal of the grip portion side of the modular connector CN1 is vacant, the first probe L1, the second probe L
2. The cathode of the light emitting diode D5, one contact of the push button switch S2, and the common of the anode of the light emitting diode D5 and the other contact of the switch S2 are connected. The switch S2 is a normally open momentary switch that is operated by a push button 28 and is normally opened and short-circuited only when pressed.

The configuration of the power supply is as follows: a DC 9 V battery BT1;
A power switch S1, voltage dividing resistors R1 and R2 for supplying a constant positive / negative voltage ± 4.5 V to a reference voltage GND obtained by dividing the voltage between the positive and negative electrodes almost equally, and stabilizing capacitors C1 and C2.
And a stabilizing capacitor C5 of a DC9V power supply.
By supplying a constant voltage of ± 4.5 V in this manner, stable operation of the amplifier IC and the comparator IC is achieved. Also,
The power line for the logic IC for the logic IC (U3) is +
A 4.5V power supply line (9V for -4.5V) is taken in via a switch S2 of the grip unit. That is, the power supply of the logic IC (U3) is the switch S
This configuration is obtained only when the second push button 28 is pressed.

The circuit operation of the circuit shown in FIG. 3 will be described.

The first probe L1 and the second probe L2 are brought into contact with the positive and negative conductors of the telephone line. At this time, since the resistors R3 and R4 having a sufficiently higher resistance value than the terminal are inserted between the probes, there is no influence even when the telephone line is in use. On the other hand, a signal from the telephone line is input to the amplifier U1A via the resistor R3. This signal is supplied to the amplifier U1
The signal is amplified by A and further amplified by the amplifier U1B. Therefore, the signal on the telephone line can be listened to by the crystal earphone LS1.

The signal amplified by the amplifier U1A is supplied to a comparator I
It is also input to C (U2) and compared with a voltage previously set by the variable resistor RV1. Note that this set voltage is set assuming that the terminal is not busy (when the telephone is a receiver). When the first probe L1 is in contact with the positive conductor of the telephone line, the second probe L2 is in contact with the negative conductor, so that the voltage from the amplifier circuit becomes higher than the set voltage, Output of IC (U2) is +
It becomes 4.5V. Conversely, when the first probe L1 is in contact with the negative conductor, the output of the comparator IC (U2) is -4.5.
V.

When the push button of the switch S2 is pressed, the logic I
Power is supplied to C (U3) and the light emitting diode D5. At this time, the output of the comparator IC (U2) is + 4.5V.
If so, the inverter U3A drives the light emitting diode D5 to light, and the oscillation circuit oscillates, so that the electronic buzzer BZ1 sounds. Conversely, if the output of the comparator IC (U2) is -4.5V, the light emitting diode D5 does not turn on,
The electronic buzzer BZ1 does not sound.

As described above, the test apparatus of the present invention has a high input resistance and amplifies the input signal, so that it is possible to listen without affecting the line. In addition, for listening, not only earphones but also speakers may be used,
The crystal earphone was selected in consideration of less failure, lower cost, lighter weight, and smaller size, and secrecy of communication.

Further, the inspection apparatus of the present invention is capable of not only listening but also confirming the polarity. A level meter or the like can be used for displaying the polarity confirmation, but an LED is preferable when priority is given to weight reduction. Further, since the electronic buzzer is used in combination, it can be confirmed by sound when the LED is not conspicuous in direct sunlight or when the visual angle is out of the directing direction of the LED.

By providing a switch function using a push button, the polarity can be displayed only when necessary. That is, since the switch S2 is of the always-open and instantaneously short-circuit type, the indicator light and the buzzer operate only when the push button is pressed, and do not operate when the push button is released. Then, since the push button 28 is provided on the grip portion 23, the operator can hold the grip portion 2 against the target line.
After approaching 3 and bringing the first probe 24 into contact with the conductor portion to perform a busy check, a type check, and the like, it is possible to shift to a polarity check in the same state.

Also, a crystal earphone or a grip 2
Since the connector 3 is detachable by a connector, it is not only convenient for carrying, but also can be easily disengaged by removing the connector when it is entangled with other equipment during use.

Further, since a battery is used, there is no need to supply power from a telephone line, and since the battery operates with a single DC 9 V battery, replacement is simplified. And this DC9V
Is divided into ± 4.5 V and each analog IC is operated with two power supplies, so that a stable operation can be obtained.

Next, a procedure for using the inspection apparatus of the present invention will be described.

The main body 21 includes the earphone 4 and the grip 2
3 is mounted, and the power switch 12 is turned on.

The first probe L1 and the second probe L2 are brought into contact with the electrodes of the terminal plate and other conductors. At this time, even if the line is a data line or a facsimile line or happens to be busy, since the resistor 2 has a higher resistance than the terminal, the conventional trouble does not occur.

At this time, if the line is busy on a general line or FA
In the case of an X line or a data line, a sound can be heard from the earphone 4.

The sound that can be heard from the earphone 4 is a specific sound according to the type of the line and the use condition. For example, a conversation voice when talking on a general line, a push dial sound during push dialing (pipopa when written in onomatopoeia), a FAX signal tone (pyrrolo), FAX when facsimile on a general line
In the case of a line or a data line, a carrier sound (P) is used. From these, the type can be confirmed.

When nothing is heard from the earphone 4, it can be determined that this line is a general line and not busy. Then, construction can be started.

To determine the polarity, push button 2
Press 8 to turn on switch 10. At this time, the indicator light 8
Is lit, and the buzzer 9 sounds, the conductor contacting the first probe L1 can be determined to be positive (if the first probe L1 is brought into contact with a conductor expected in advance to be positive) , The prediction is correct). Conversely, if the indicator lamp 8 does not light up and the buzzer 9 does not sound, it can be determined that the conductor contacting the first probe L1 has negative polarity.

Next, the performance of the inspection apparatus of the present invention and the performance of the conventional inspection apparatus will be compared. First, a standard test pattern shown in FIG. 6 is prepared. The standard test pattern consists of several simple figures. This standard test pattern is
X Send and receive. Each inspection device is brought into contact with the telephone line during transmission and reception. The images received at this time are compared for each inspection device.

FIG. 7 is a received image when the line test handset is brought into contact. In this received image, horizontal scanning lines are missing in some places. In this way, it can be seen that defects such as the image jump 71 and the image disturbance 72 are very conspicuous.

FIG. 8 is a received image when the crystal earphone is brought into contact. This received image does not have a noticeable drop as shown in FIG. 7, but has a disadvantage that the image jumps 81 at the moment of contact with the line.

FIG. 9 is a received image when the LED insertion type inspection device is brought into contact. The defects are very noticeable.

FIG. 10 is a received image when the lamp type busy checker is brought into contact. The image is flying the moment you touch the line.

FIG. 11 is a received image when the inspection apparatus of the present invention is brought into contact. This is exactly the same as the standard test pattern shown in FIG. 6, and it can be seen that the inspection apparatus of the present invention has no influence on FAX transmission / reception. Therefore, since there is no inconvenience to the user, the telephone construction worker can engage in the work with peace of mind.

Next, the effects on the line by the inspection capability and type of each inspection device are listed and compared.

[0053]

[Table 2]

As shown in Table 2, those with a double circle in the column of "confirmation judgment" can be used, but those with a cross cannot be used. Therefore, it is understood that there is no inspection device that can be used for all inspections. On the other hand, the inspection devices of the present invention are all double circles, and one device can be used for all inspections.

In the column of "degree of influence on line", the line with a double circle has no effect on the line when connected to the line, and the one with a triangle mark indicates the effect on the line. Those marked with a cross have a large effect on the line. It can be seen that the influence on the FAX transmission / reception and data transmission / reception is large in common with each conventional inspection apparatus. That is, if these inspection devices come into contact with the data line, the system will go down or an error will occur, and if they come into contact with the line during fax transmission, the image will be dropped. On the other hand, the inspection apparatus of the present invention is a double circle, and can inspect without affecting the line regardless of the type of the line.

The inspection apparatus of the present invention can be used for both analog and digital data lines.
N lines, general dedicated lines, high-speed digital lines, code lines,
It can be used for all broadcast lines, music broadcast lines, and no-re-king lines.

[0057]

The present invention exhibits the following excellent effects.

(1) Since the listening circuit and the polarity display circuit are provided, all the inspections of the polarity, telephone call, and type of the telephone line can be performed.

(2) Since a resistor having a resistance value sufficiently higher than that of the subscriber terminal is provided, the inspection can be performed without affecting the line in use.

[Brief description of the drawings]

FIG. 1 is a block diagram of a telephone line inspection apparatus according to the present invention.

2A is a front view of the main body, FIG. 2B is a top view of the main body, and FIG.

FIG. 3 is a circuit diagram of a telephone line inspection apparatus according to the present invention.

FIG. 4 is a wiring diagram of a telephone line to be constructed.

FIG. 5 is a wiring diagram of an MDF.

FIG. 6 is a diagram of a transmission image of a standard test pattern.

FIG. 7 is a diagram of a received image when the line test handset is brought into contact with the handset.

FIG. 8 is a diagram of a received image when a crystal earphone is brought into contact.

FIG. 9 is a diagram of a received image when the LED insertion type inspection device is brought into contact with the inspection device.

FIG. 10 is a diagram of a received image when a lamp type busy check device is brought into contact with the lamp.

FIG. 11 is a diagram of a received image when the inspection device of the present invention is brought into contact with the inspection device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Probe 2 Resistor 3 Amplifier circuit 4 Earphone 5 Listening circuit 6 Polarity display circuit 7 Judgment circuit 8 Indicator light 9 Buzzer 10 Switch

Claims (4)

[Claims] 1. A probe for contacting a conductor of a telephone line, a resistor connected to the probe and having a sufficiently higher resistance value than a subscriber terminal, and a voltage detected by the resistor. A telephone circuit comprising: an amplifier circuit for amplifying the amplified signal; a listening circuit for driving an earphone with the amplified signal; and a polarity display circuit for displaying the polarity of the conductor portion based on the level of the voltage of the amplified signal. Line inspection equipment. 2. A polarity display circuit comprising: a determination circuit for determining that the polarity of the conductor portion is correct when a voltage of the amplified signal is higher than a predetermined determination voltage; and an indicator lamp for lighting and displaying the determination. 2. The telephone line inspection apparatus according to claim 1, further comprising a buzzer for displaying the judgment. 3. The apparatus according to claim 1, further comprising: a switch for switching between operation and non-operation of the indicator light and the buzzer.
Or the telephone line inspection device according to 2. 4. The telephone line inspection apparatus according to claim 3, wherein the switch is arranged on one side of a grip portion for supporting the probe by projecting the probe.