SU1401640A1 - Device for acoustic calling of subscriberъs telephone - Google Patents

Abstract

The invention relates to the field of telephony and is intended for use in conjunction with a telephone set included in a subscriber line. The aim of the invention is to exclude a fake call after a call. The device contains a lever switch 3, a microphone 4, an e.1ectro-acoustic transducer (EAP) 5. To achieve its purpose in the input device, the circuit-closure recorder 1, having output terminal 10, the current-directional distribution element 2, has input 14 and two outputs 9 and 13, as well as switch 6, which has four terminals 7, 8 and 11, 12. If the subscriber ends the conversation first and hangs up to pickup from the central station, switch 6 remains in the disconnected state, and therefore , - and battery status is the same as in conversation. The element 2 again directs the current towards the switch 6, which is held in the switched state. Consequently, the EAP 5 does not excite electro-acoustic oscillations after the subscriber has disconnected and does not give a false call signal. 1 n.i. S (l

Description

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The invention relates to telephony and is intended for use in conjunction with a telephone set included in a subscriber line.

The aim of the invention is to exclude a fake call after a call.

The drawing shows a block diagram of the device acoustic call subscriber telephone.

The device for acoustic call of the subscriber's telephone set contains the circuit-clocking recorder 1, current directional distribution element 2, lever switch 3, microphone 4, electroacoustic converter 5, battery polarity switch 6, switch 7 pin 7, coder 6 pin 8, output 9 of element 2 , output 10 of registrar 1, output 11 of switch 6, output 12 of co.mutator 6, output 13 1 of element 2, input 14 of element 2.: The device works as follows. ; At the telephone station, the calling signal: is combined with the switching on of the microphone supply voltage to the side; The subscriber line, the polarity of the battery is switched on so that the output 7: the negative pole of the stationary battery is applied, and the output 8 is positive. Station battery voltage; in such polarity, through the switch 6, 1 to 1 polarity of the battery and through the lever switch: the switch 3 is fed to the input 14 of the element 2 I of the current direction distribution, which I, at this polarity, opens its output 9, from which Voltage 1 is fed to the input of the electroacoustic converter 5. The latter converts: the voltage of the direct current into electroacoustic tonal frequency oscillations, signaling about the call.

After the subscriber answers, the lever switch 3 breaks the voltage sending circuit through element 2 towards the electroacoustic converter 5, which turns off and stops the generation of electro-acoustic oscillations.

In addition, the lever switch 3 closes the circuit of the microphone 4, in series with which the recorder 1 closes the circuit. The latter is switched on by the current of the microphone circuit and, from its output 10, gives the command to turn on switch b, which at its terminals 11 and 12 re-switches the polarity of the station battery to the opposite one. As a result of the polarity polarity reversal, from the output 13 of the element 2 to the input of the switch b, a potential is applied, which keeps the switch 6 in the on state until withdrawn from the central station.

If the subscriber ends the conversation first and hangs up the telephone lever before being picked up by the central station, the switch b remains in the switched state, and therefore the polarity of the battery remains in the same state as during the conversation. The element 2 at the same time again directs the current towards the switch b, which is kept in the switched state; therefore, the electro-acoustic transducer 5 does not excite electro-acoustic oscillations after the subscriber has disconnected and does not give a false call signal. After being disconnected from the central station, the acoustic call device of the subscriber telephone is de-energized and returns to its original state.

Claims (1)

Invention Formula An acoustic telephone call subscriber device comprising a lever switch, a microphone and an electroacoustic transducer, characterized in that, in order to avoid a spurious call after pick-up, a circuit fault recorder, a current direction distribution element and a battery polarity switch are introduced into it, the first and second terminals which, respectively, are the first and second terminals of the acoustic calling device of the subscriber’s telephone, the third terminal is connected to the first terminal of the lever switch, and the fourth output - to the first input of the electroacoustic converter and the first microphone output, the second output of which is connected to the first output of the circuit-closure recorder, the output of which is connected to the input of the battery polarity switch and the first output of the current direction distribution element, the second output of which is connected to the second the input of the electroacoustic converter, and the first and second inputs, respectively, to the second and third pins of the lever switch, while the second output of the recorder is Addi ctive circuit connected to the third terminal of the switch lever.