CN2319967Y

CN2319967Y - Telephone with self-jamming for preventing line wiretapping

Info

Publication number: CN2319967Y
Application number: CN 97234171
Authority: CN
Inventors: 黄秉和
Original assignee: Individual
Current assignee: Individual
Priority date: 1997-09-03
Filing date: 1997-09-03
Publication date: 1999-05-19
Anticipated expiration: 2007-09-03

Abstract

The utility model relates to a self-jamming telephone for preventing line wiretapping, comprising a common telephone and a circuit of the common telephone. The utility model is characterized in that a noise generator, a transfer switch K1 (3) and a key K2 (4) are added; a power supply end of the noise generator is connected with a power supply of the telephone circuit, and an output end is connected with an output end of a microphone of the telephone through K2 and K1 which are arranged on a shell. Points 6, 5 and 2 of the K2 are connected with the K1. Points 2 and 3 of the K2 are connected with a receiver (2). The utility model can prevent line wiretapping, especially induction wiretapping and radiate wiretapping.

Description

The telephone set of the anti-circuit eavesdropping of oneself's interfering type

The utility model relates to a kind of telephone set.

There are some that antitheft device is housed in the existing common wire telephone, the doubling eavesdropping is had certain privacy functions, but powerless to induction eavesdropping and radiation eavesdropping.

The purpose of this utility model provides the telephone set of the anti-circuit eavesdropping of a kind of self-interfering type, and it can remedy the above-mentioned deficiency of existing telephone machine.

The utility model comprises the circuit of an ordinary telephone set and ordinary telephone set, it is characterized in that increasing a noise generator, change over switch K ₁With button K ₂, the power end of noise generator is connected on the power supply of telephone set network, and output passes through K ₂, K ₁Be connected on the output of telephone set transmitter, K ₁And K ₂Be contained on the

casing K

₂6 and 5 and K ₁Connect K ₂2 be connected with receiver with 3.

The utility model can prevent wiretapping, particularly can prevent induction eavesdropping and radiation eavesdropping.

Accompanying drawing 1 is an external structure schematic diagram of the present utility model.

Accompanying drawing 2 is K _A-200 type telephone set network figure.

Accompanying drawing 3 is noise generator of the present utility model, change over switch K ₁With button K ₂Circuit diagram.

The utility model comprises for example K of an ordinary telephone set _A-200 type telephone sets, its circuit as shown in Figure 2.Increase a noise generator, a change over switch K ₁(3) and button K ₂(4), the former places in the casing of ordinary telephone set, and the latter two then place on the telephone case.Noise generator in the present embodiment is by triode T ₁, T ₂With composition such as voltage stabilizing didoe, as shown in Figure 3, the noise that its produces passes through K ₁, K ₂Conversion to realize secret telephony.The a point of noise generator is connected on K _A-200 type telephone set BG ₁Collector electrode on, its b point is connected on this phone BG ₅Emitter on.Change over switch K ₁The C point be connected on the capacitor C of telephone set ₈Right-hand member, its A point is connected on an end that is connected with transmitter (1) of disconnection, simultaneously capacitor C ₈Right-hand member and transmitter (1), capacitor C ₉And resistance R ₁₄The line that links to each other disconnects.Disconnect R in receiver (2) and the phone ₂₈Connecting line, K ₂2 open ends with receiver (2) be connected K ₂3 with disconnect and R ₂₈An end that connects connects,

K

₂6 and 5 respectively with K ₁The A point be connected with the B point.

For transmitter signal and receiver signal are separated more reliably, the noise that further suppresses oneself to produce enters in the receiver of oneself, can increase the better buffer circuit of performance, hybrid circuit and the balancing network used when adopting two lines in the switch/four line conversion replace the anti-side-tone circuit in the telephone set.

Work as K ₁Get to the A point, K ₂When not pressing, noise generator output is disconnected, and can not send noise, and transmitter (1), receiver (2) are connected, and it is a common phone, can not anti-eavesdrop; K ₁Reach the B point, K ₂Be late for

K

₂2,3 connections, 4,5 connections, receiver this moment (2) is connected, transmitter (1) disconnects, the noise of noise generator output is delivered on the circuit by the amplifying circuit of transmitter (1), isolate mutually because transmitter (1) and receiver (2) are original, so noiseless output in the receiver (2) has only the speech output on the circuit.So can only listen to speech.

Work as K ₁Get to the B point and press K ₂The time,

K

₂2,3 disconnections, 4,5 disconnections, 5,6 connections, this moment receiver (2) be disconnected, the output of noise generator has also disconnected, and has only transmitter (1) to connect, so can only give orders or instructions.

How two such telephone sets of both sides form an anti-eavesdrop phone system

During both sides' normal talking, all K ₁Get to the A end, K ₂Do not press; When changing secret telephony over to, both sides will be the K of own phone ₁Dial and hold at B.

If the Party A gives orders or instructions, the Party B listens to, and then the Party A presses K ₂Speech, the Party B is not according to K ₂Listen to.The speech that the noise that this moment, Party B's phone sent and Party A's phone send mixes on the line, to prevent eavesdropping.

If the Party B gives orders or instructions, the Party A listens to, and then the Party B presses K ₂Give orders or instructions, the Party A is not according to K ₂Listen to, the speech that the noise that this moment, Party A's phone sent and Party B's phone send mixes on the line with anti-eavesdrop.

This method is the noise that own telephone set produces to be delivered on the circuit be mixed together on the line with speech, speech is submerged in the noise, how no matter listener-in on the circuit eavesdropped, what receive all is a slice noise, and listener is only received speech, can not receive noise, reach the purpose of anti-circuit eavesdropping with this.

Claims

1. a self-interfering type is prevented the telephone set that circuit is eavesdropped, and comprises the circuit of an ordinary telephone set and ordinary telephone set, it is characterized in that increasing a noise generator, change over switch K ₁(3) and button K ₂(4), the power end of noise generator is connected on the power supply of telephone set network, and output passes through K ₂, K ₁Be connected on the output of phone transmitter, K ₁, K ₂Be contained on the casing K ₂6 and 5 and K ₁Connect K ₂2 be connected with receiver (2) with 3.

2. as claim 1 described telephone set, it is characterized in that replacing anti-side-tone circuit in the described ordinary telephone set with hybrid circuit in the switch and balancing network.