CN2229737Y

CN2229737Y - Telephone set with secrecy device in party-line system of exchange

Info

Publication number: CN2229737Y
Application number: CN 95240619
Authority: CN
Inventors: 唐宗才
Original assignee: Individual
Current assignee: Individual
Priority date: 1995-10-05
Filing date: 1995-10-05
Publication date: 1996-06-19
Anticipated expiration: 2005-10-05

Abstract

The utility model discloses a telephone set with a secrecy device in party-line system of exchange, which comprises a ringing circuit, a polar protection circuit, an on-off circuit, a dialing circuit, a talking circuit and an anti-theft secrecy circuit, wherein, the anti-theft secrecy circuit comprises a line work detection circuit, an extension work discrimination circuit, a switch circuit, a jamming signal control circuit and an extension secrecy circuit. The utility model collects the functions of the anti-theft and extension talking secrecy into a whole, and can prevent the phenomenon that telephone lines are embezzled by other people occurring.

Description

The stolen telephone set of anti-circuit with extension set secure line

The utility model relates to a kind of telephone set, specifically a kind ofly prevents that other people from illegally incorporating circuit into, usurps telephone set, and has and can install extension set, each extension set additional with the telephone set with function of keeping secret.

At present, on teleset line, illegal phone in parallel, free call on somebody else's expense through illegal means happens occasionally, and free call on somebody else's expense through illegal means is difficult for finding.On the market multiple Device for anti-fraudulent use telephone line is arranged also now, be installed in the outside of telephone set, volume is bigger, and function singleness uses comparatively inconvenience.And the situation of two above telephone sets in parallel is quite general on a number lines, and phone scarcely possesses function of keeping secret, must install the extension set scrambler additional in the phone outside in addition.Do not maintain secrecy but commercially available various Device for anti-fraudulent use telephone line all do not possess extension set, and extension set is maintained secrecy and is not also possessed the fraudulent use of telephone of preventing function; If all there is the cost height in additional above device, insecure shortcoming of working outside telephone set.

Based on above-mentioned situation, can collect anti-theft circuit and secure circuit in telephone set.At ordinary times, the testing circuit work in the antitheft phone, when fraudulent use of telephone, interference signal is sent in anti-theft circuit work, and robber's machine can't be worked.When antitheft telephone set or extension set work, turn-off interference signal, enable the extension function of keeping secret simultaneously.

The purpose of this utility model just provides and a kind ofly prevents that other people illegal parallel connection from entering the free call on somebody else's expense through illegal means of phone circuit, and antitheft telephone set or extension set normal two have function of keeping secret between each telephone set when doing.

The inner basic circuit of the design's telephone set comprises ringing circuit 7, polar protective circuit 8, on-off circuit 6, dial-up circuit 9, speaking circuit 10 and antitheft secure circuit L.

Wherein on-off circuit is the circuit of control local network and loop break-make (off-hook and on-hook), it in handle telephone switch hook, being hands-free switch in hand-free telephone, is the relay or the electronic switch of control line loop break-make in other telephone sets such as cordless telephone.

Antitheft secure circuit comprises line work testing circuit 1, extension set work discriminator circuit 2, switching circuit 3, interference signal control circuit 4, extension set secure circuit 5.

Wherein the line work testing circuit is attempted by after the polar protective circuit; switching circuit cross-over connection on-off circuit; extension set work discriminator circuit and extension set secure circuit are serially connected between polar protective circuit and the on-off circuit, and the interference signal control circuit is connected between line work testing circuit and the signaling circuit.

The utility model has the advantages that and to stop other people illegal phreaking, and can connect the multi-section extension set, and when using, have the conversation function of keeping secret.

Accompanying drawing 1 is one of the utility model schematic circuit.

Accompanying drawing 2 is two of the utility model schematic circuit.

Wherein: 1, line work testing circuit; 2, extension set work discriminator circuit; 3, switching circuit; 4, interference signal control circuit; 5, extension set secure circuit; 6, on-off circuit; 7, ringing circuit; 8, polar protective circuit; 9, signaling circuit; 10, speaking circuit.

Be described further below in conjunction with accompanying drawing.

As shown in Figure 1, the line work testing circuit is by a triode BG ₁Constitute, switching circuit is by triode BG ₂Emitter and triode BG ₃Base stage connect and to form, and triode BG ₃Emitter and collector be connected across on the on-off circuit; The interference signal control circuit is by a triode BG ₅Constitute, its collector and emitter respectively with keyboard on the lead-in wire of " * " number key (or " # " key) join its base stage and triode BG ₂Base stage, triode BG ₁Emitter connect.

When telephone line does not have telephone set work, the direct voltage of 24V or 36V or 48V or 60V is arranged, the BG in the extension set work discriminator circuit between the telephone set terminals 11,12 ₄End the BG in the line work testing circuit ₁Conducting, the interference signal control circuit is in off-state, simultaneously the BG in the switching circuit ₂, BG ₃All end, switching circuit is in off state, and the signaling circuit non-transformer is supplied with.

When illegal access of phone and off-hook were arranged on the circuit, voltage dropped to about 10V between the telephone set terminals 11,12, thereby makes the BG in the line work testing circuit ₁End the BG in the interference signal control circuit ₅Conducting, simultaneously, the BG in the switching circuit ₂, BG ₃Conducting, this moment, switching circuit was in open mode, and telephone set sends " * " signal, and robber's machine can't be got through, simultaneously light-emitting diode D ₄Bright, report to the police.

When antitheft telephone set or extension set operate as normal, the voltage-stabiliser tube DW on the respective branch is punctured controllable silicon SCR conducting, the BG in the extension set work discriminator circuit ₄The BG in the line work testing circuit is given in conducting ₁Provide bias current to make BG ₁Conducting, the BG in the switching circuit ₂, BG ₃End the BG in the interference signal control circuit ₅Also end, telephone set can operate as normal.

During any telephone set operate as normal in antitheft telephone set or the extension set, other phone since on the circuit voltage reduce, the voltage-stabiliser tube DW on its branch road can not puncture, controllable silicon SCR can't conducting and can not work.Thereby reach the privacy functions of conversing between each telephone set.

Accompanying drawing 2 is depicted as the antitheft teleset line of not being with extension set.

Antitheft secure circuit L can be simplified to anti-theft circuit L ', anti-theft circuit L ' only comprises line work testing circuit and switching circuit.

In the figure, the hands-free K switch of switch hook at ordinary times ₁, K ₂1,2 communicate, this moment BG ₁Conducting, BG ₂Ending, does not work in antitheft telephone set loop, and when people's free call on somebody else's expense through illegal means, line work voltage descends, BG ₁On cutting, BG ₂Conducting, BG ₃Also conducting, at this moment antitheft telephone set loop works is because " * " key passes through K ₂1,2 ends link to each other, this moment, telephone set sent " * " signal, robber's machine can't be got through.While light-emitting diode D ₁Bright, report to the police.

When antitheft telephone set operate as normal, take receiver or press hands-free switch, K ₁, K ₂1,3 ends communicate, 1,2 ends disconnect, this moment, testing circuit was cut off, antitheft telephone set can operate as normal.

Claims

1, a kind of have an anti-stolen telephone set of circuit of extension set secure circuit; the inner basic circuit of its telephone set comprises ringing circuit (7), polar protective circuit (8), on-off circuit (6), dial-up circuit (9), speaking circuit (10) and antitheft secure circuit (L), wherein:

On-off circuit is the circuit of control local network and loop break-make (off-hook and on-hook), it in handle telephone switch hook, being hands-free switch in hand-free telephone, is the relay or the electronic switch of control line loop break-make in other telephone sets such as cordless telephone.

It is characterized in that:

Antitheft secure circuit (L) comprises line work testing circuit (1), extension set work discriminator circuit (2), switching circuit (3), interference signal control circuit (4), extension set secure circuit (5);

Line work testing circuit (1) is attempted by polar protective circuit (8) afterwards; switching circuit (3) cross-over connection on-off circuit (6); extension set work discriminator circuit (2) and extension set secure circuit (5) are serially connected between polar protective circuit (8) and the on-off circuit (6), and interference signal control circuit (4) is connected between line work testing circuit (1) and the signaling circuit (9).

2, the stolen telephone set of anti-circuit with extension set secure circuit according to claim 1, it is characterized in that: line work testing circuit (1) is by a triode BG ₁Constitute, switching circuit (3) is by triode BG ₂Emitter and triode BG ₃Base stage connect and to form, and triode BG ₃Emitter and collector be connected across on the on-off circuit (6); Interference signal control circuit (4) is by a triode BG ₅Constitute, its collector and emitter respectively with keyboard on the lead-in wire of " * " number key (or " # " key) join its base stage and triode BG ₂Base stage, triode BG ₁Emitter connect.

3, the stolen telephone set of anti-circuit with extension set secure circuit according to claim 1, it is characterized in that: extension set secure circuit (5) is made of some extension set branch roads in parallel, the circuit structure of each extension set branch road is identical, all is to be connect by a controllable silicon and a voltage stabilizing didoe to form.

4, the stolen telephone set of anti-circuit with extension set secure circuit according to claim 1, it is characterized in that: antitheft secure circuit (L) can be simplified to anti-theft circuit (L '), anti-theft circuit (L ') only comprises line work testing circuit and switching circuit.