CN102572125A

CN102572125A - Telephone stealing apprizing device

Info

Publication number: CN102572125A
Application number: CN2012100345690A
Authority: CN
Inventors: 何林
Original assignee: Individual
Current assignee: Individual
Priority date: 2012-02-15
Filing date: 2012-02-15
Publication date: 2012-07-11

Abstract

The invention belongs to the technical field of telephone communication, and relates to a telephone stealing apprizing device. The telephone stealing apprizing device comprises a telephone line, a telephone circuit polarity identifying circuit, a stealing signal identifying circuit, a sound and light driving circuit, a telephone terminal polarity identifying and isolating circuit. The telephone stealing apprizing device has the following characteristics and functions: a telephone line stolen apprizing function, if the phenomenon that nobody uses a telephone at home is found, a buzzer on the device rings suddenly and a red light-emitting diode is also lighted, a receiver of the stolen telephone gives harsh reference noise, the stolen telephone is forced not to be dialed and hung up, the situation that someone is stealing the telephone line is apprized to a host, the host can detect an outdoor telephone line timely by himself/herself to view whether an abnormal phenomena exists in the telephone line or ask the professional personnel in the telephone station to detect and maintain the telephone line immediately.

Description

Telephone set steal informing device

Technical field

The invention belongs to the telephonic communication technical field, relate to a kind of telephone set steal informing device.

Background technology

Nearly all fixed telephone does not all design preventing telephone from dialing without admission or by the free call on sb. else's expense through illegal means prompting function on the market.Some people had such cognition; Be exactly that the family expenses fixed telephone is when the machine of carrying is called; Falling in has the sound of conversing in the phone; Perhaps telephone charges is touched the fan increases a lot cleverly and finds that it is not number own or that the household dials that conversation has some on single, and this phenomenon occurs in telephone line especially easily and pulls the chaotic place of comparison, the reply way also good to this kind phenomenon telephone operator.For effectively solving the technical problem of this respect; On the basis that does not change original telephone set internal structure and circuit; The present invention utilizes the characteristics of telephone line and telephone set, uses a small amount of discrete electronic devices and components, has well solved home telephone once in a while by the problem of free call on sb. else's expense through illegal means.

Below specify telephone set steal informing device and implementing to relate to correlation technique related in the process.

Summary of the invention

Goal of the invention and beneficial effect

Telephone set steal informing device of the present invention has following characteristics and effect: the stolen informing function of telephone line; If find that nobody uses phone in the family; And the buzzer on this device sounds suddenly, red light emitting diodes is also lighted, and usurps simultaneously in the receiver of telephone set and will send ear-piercing interfering noise, forces steal phone person to dial and on-hook; At this moment inform that owner has the people usurping your family's phone circuit; You can in time check outdoor telephone line voluntarily, examine whether have anomaly on the telephone line, or ask the specialty of telephone office to rank among personnel inspection, maintenance telephone circuit immediately.The present invention does not change original fixed telephone inner circuit and structure, and original fixed telephone method for using and original function do not change.

The operation principle of circuit: telephone set steal informing device can monitor and prevent that other people from usurping your telephone line.As on the outside line of people at you during parallel operation steal phone, this device will send interference signal, and the person can not dial to make the steal, and has informed people's steal phone through sound, light mode to owner.Operation principle map analysis according to telephone set steal informing device; The standby voltage that 48～50V is arranged on the outside line at ordinary times approximately; Through 4 switching diode D1～D4 polar switching; Voltage stabilizing didoe DW punctures through resistance R 2 raises the base potential of NPN transistor VT1, and NPN transistor VT1 conducting, NPN transistor VT2 end.When people's steal telephone set, telephone line voltage drops to about 10V, and voltage stabilizing didoe DW is punctured; NPN transistor VT1 ends because of no-bias; NPN transistor VT2 base potential rising conducting, the conducting of NPN transistor VT2 make that buzzer YA sounds a buzzer, the luminous prompting of LED, and the voltage of telephone line is dragged down; Usurp simultaneously in the receiver of telephone set and can send ear-piercing interfering noise, force steal phone person to dial and can only on-hook.Though owner carries machine telephone line voltage is reduced; And NPN transistor VT1 is ended; (access of two NPN transistor VT3, VT4 is the machine of having a telephone installed for ease but because of NPN transistor VT3 or NPN transistor VT4 obtain the base current conducting through telephone set; Need not distinguish polarity when inserting house lead in; Rectifier diode D5, D6 play buffer action at circuit), thereby be connected to the very little resistance R of resistance 4, resistance R 5 between owner's telephone set and the outside line, so ring, normal dialing and conversation when calling are all unaffected.

Technical scheme: telephone set steal informing device, comprise telephone line, telephone line polarity identification circuit, steal signal recognition circuit, acousto-optic drive circuit, telephone set binding post polarity identification and buffer circuit, it is characterized in that:

The telephone line polarity identification circuit: telephone line patch terminal L1, L2 are connected on the full bridge rectifier input that is connected into by 4 switching diode D1～D4 respectively; The anodal VCC of the anodal connection circuit of full bridge rectifier output, the negative pole connection circuit ground GND of full bridge rectifier output;

Free call on sb. else's expense through illegal means signal recognition circuit: the anodal VCC of the termination circuit of dropping resistor R1; The negative pole of another termination voltage stabilizing didoe DW of dropping resistor R1; The positive pole of voltage stabilizing didoe DW connects an end of base stage and the resistance R 2 of NPN transistor VT1; The other end connection circuit ground GND of the emitter of NPN transistor VT1 and resistance R 2, the anodal VCC of collector series connection resistance R 3 back connection circuits of NPN transistor VT1;

Acousto-optic drive circuit: form by NPN transistor VT2, LED, buzzer YA; The base stage of NPN transistor VT2 connects the collector electrode of NPN transistor VT1; The emitter connection circuit ground GND of NPN transistor VT2; The negative pole of the collector electrode sending and receiving optical diode LED of NPN transistor VT2, the anodal VCC of connection circuit behind the positive pole serial connection buzzer YA of LED;

Telephone set binding post polarity identification and buffer circuit: form by NPN transistor VT3, silicon diode D5, resistance R 4 and NPN transistor VT4, silicon diode D6, resistance R 5; The collector electrode of NPN transistor VT3 connects the negative pole of silicon diode D5; The positive pole of silicon diode D5 connects the collector electrode of NPN transistor VT1; An answer the call end of sub-L1 of line input and resistance R 4 of the emitter of NPN transistor VT3, the other end of the base stage connecting resistance R4 of NPN transistor VT3 and telephone set binding post L3; The collector electrode of NPN transistor VT4 connects the negative pole of silicon diode D6; The positive pole of silicon diode D6 connects the collector electrode of NPN transistor VT1; An answer the call end of sub-L2 of line input and resistance R 5 of the emitter of NPN transistor VT4, the other end of the base stage connecting resistance R5 of NPN transistor VT4 and telephone set binding post L4.

Description of drawings

Accompanying drawing 1 is the circuit working schematic diagram of telephone set steal informing device; L1 in the accompanying drawing 1, L2 are respectively the telephone line input terminal; L3, L4 are respectively the machine binding post of answering the call in the accompanying drawing 1.

Embodiment

Specification requirement according to the components and parts of the circuit working schematic diagram of the informing device of telephone set steal shown in the accompanying drawing 1 and description of drawings and the following stated is implemented, and can realize the present invention.

The selection of components and parts and technical parameter thereof

VT1～VT4 is a NPN transistor, and selecting model for use is 2SC9013;

D1～D4 is the glassivation switching diode, and selecting model for use is 1N4148;

DW is a voltage stabilizing didoe, and its voltage stabilizing value is 15V, and power is 0.5W;

D5, D6 are silicon rectifier diode, and model is 1N4001;

Resistance is selected 1/8W metalfilmresistor or fixed carbon resister for use, and the resistance of resistance R 1 is 5.1K Ω, and the resistance of resistance R 2 is 20K Ω, and the resistance of resistance R 3 is 6.2K Ω, and the resistance of resistance R 4 and R5 is 51 Ω;

LED is a red light emitting diodes;

YA is the buzzer of 12V, requires its inside to contain the audio electronics circuit.

Circuit production main points and circuit debugging

Measure direct voltage between telephone line input terminal L1, the L2 whether between 47～50V with digital multimeter; If the voltage of telephone line input is on the low side; Answer phenomenons such as whether having loose contact on the scrutiny telephone line, telephone line must guarantee that telephone set can normally dial or receive calls;

The base voltage of inspection, measuring N PN transistor npn npn VT1 should be greater than 5V behind the telephone set off-hook; Guarantee the reliable conducting of NPN transistor VT1; NPN transistor VT2 reliably ends simultaneously, makes the acousto-optic drive circuit not work, and can normally dial or receive calls; As if reliably conducting of NPN transistor VT1, can suitably increase the resistance of resistance R 2;

Insert a telephone set at telephone line input terminal L1, L2; Be used to simulate the behavior of steal phone; Behind this one " steal " telephone set off-hook, NPN transistor VT1 is become by conducting and ends, and NPN transistor VT2 is by by transferring conducting to; Buzzer YA and LED that NPN transistor VT2 collector electrode is connect must be established beginning work by cable, at this moment in the receiver of this one " steal " telephone set, should be able to hear harsh noise.If the noise in the telephone receiver is big inadequately, can suitably reduce the resistance of resistance R 3.

Claims

1. a telephone set steal informing device comprises telephone line, telephone line polarity identification circuit, steal signal recognition circuit, acousto-optic drive circuit, telephone set binding post polarity identification and buffer circuit, it is characterized in that:

Telephone line patch terminal L1, L2 are connected on the full bridge rectifier input that is connected into by 4 switching diode D1～D4 respectively in the telephone line polarity identification circuit; The anodal VCC of the anodal connection circuit of full bridge rectifier output, the negative pole connection circuit ground GND of full bridge rectifier output;

The anodal VCC of the termination circuit of dropping resistor R1 in the free call on sb. else's expense through illegal means signal recognition circuit; The negative pole of another termination voltage stabilizing didoe DW of dropping resistor R1; The positive pole of voltage stabilizing didoe DW connects an end of base stage and the resistance R 2 of NPN transistor VT1; The other end connection circuit ground GND of the emitter of NPN transistor VT1 and resistance R 2, the anodal VCC of collector series connection resistance R 3 back connection circuits of NPN transistor VT1;

The acousto-optic drive circuit is made up of NPN transistor VT2, LED, buzzer YA; The base stage of NPN transistor VT2 connects the collector electrode of NPN transistor VT1; The emitter connection circuit ground GND of NPN transistor VT2; The negative pole of the collector electrode sending and receiving optical diode LED of NPN transistor VT2, the anodal VCC of connection circuit behind the positive pole serial connection buzzer YA of LED;

Telephone set binding post polarity identification and buffer circuit are made up of NPN transistor VT3, silicon diode D5, resistance R 4 and NPN transistor VT4, silicon diode D6, resistance R 5; The collector electrode of NPN transistor VT3 connects the negative pole of silicon diode D5; The positive pole of silicon diode D5 connects the collector electrode of NPN transistor VT1; An answer the call end of sub-L1 of line input and resistance R 4 of the emitter of NPN transistor VT3, the other end of the base stage connecting resistance R4 of NPN transistor VT3 and telephone set binding post L3; The collector electrode of NPN transistor VT4 connects the negative pole of silicon diode D6; The positive pole of silicon diode D6 connects the collector electrode of NPN transistor VT1; An answer the call end of sub-L2 of line input and resistance R 5 of the emitter of NPN transistor VT4, the other end of the base stage connecting resistance R5 of NPN transistor VT4 and telephone set binding post L4.