RU1838886C - Automatic telephone responder - Google Patents

Description

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WITH

The invention relates to telephony and can be used in devices for automatically transmitting a response and recording messages over a telephone line.

The purpose of the invention is to simplify the design of the device and increase the reliability of disconnection.

Functional diagram of the proposed device is shown in the drawing.

The proposed automatic telephone transponder comprises a ringing signal conversion unit 1, the output of which is connected to the input of the RS-trigger 2 installation, and the trigger output is connected to the control relay 3. The disconnecting contacts 4 of the control relay 3 are connected between the input of the ringing signal conversion unit 1 and the first output 5 of the telephone line, and the NO contact is connected to the output of the response unit 6, to the input of the message recording unit 7, and to the input of the shutdown unit 8. Block

shutdown 8 consists of a series-connected amplifier 9, detector 10, a two-threshold comparator 11 and an inverter 12, an input is also connected to the input of amplifier 9. There is no message control unit 13, its output is connected to the first input of AND element 14, the second input of And element is connected to output integrator 12, and the output of the And element, which is the output of the shutdown unit 8, is connected to the reset input of the RS flip-flop 2. The second terminal 15 of the telephone line is connected to a common bus 16 of the device.

The proposed automatic telephone responder operates as follows;

When the call signal is received from the telephone line, the call signal conversion unit 1 generates a logic signal at its output, which sets the RS trigger 2 to a single state.

00 GO 00 00 00 O

with

The call signal conversion unit 1, in the general case, is a detector and a comparator and monitors the occurrence of a call signal, which is a 60-VAC alternating current with a frequency of 0.4 Hz (the frequency can be different, for example, for long-distance communication , and does not affect the answering machine) ..

The call signal conversion unit 1 does not pass direct current, this is an irreplaceable condition for the receipt of a call signal, because otherwise given telephone line given number) for all subscribers will be Busy.

The output of the RS flip-flop 2 includes a control relay 3, which disconnects the telephone line from the ring signal conversion unit 1 and includes a response unit 6, a message recording unit 7, and a shutdown unit 8. This creates a path for the direct current of the telephone line, which is a necessary condition for holding the line. The response unit 6 transmits the previously recorded phrase to the telephone line. Response block 6 can be implemented, for example, on the basis of a tape recorder with a closed loop of magnetic tape, But other principles can be used, in particular, in the current layout made by the author, a response block is used, made on the basis of digital memory chips with a digital-to-analog converter . The message recording unit 7 is activated simultaneously by the response unit, thus the phrase of the answering machine and the following. the message is recorded sequentially one after another. An answering machine phrase usually takes about 10 seconds. This slightly reduces the capacity of the message recording unit 7, but it turns out to be useful when, for example, a tape recorder with automatic adjustment of the recording level (ARUZ) is used as the message recording unit 7 and when it is turned on in the Recording mode, it takes about 10 seconds automatic setting of the required recording level, and the part of the message being recorded at this time (in this case, the messageless phrase of the answering machine) undergoes significant distortion. Messages coming from the telephone line are recorded in the message recording unit 7 in order of priority.

The shutdown unit 8 is used to turn off the answering machine when a hang up signal appears in the telephone line. This signal is established on the PBX line when the person on the line hangs up.

The constant charge and discharge of the capacitance of the detector 10 is selected so that the level of the output voltage of the detector does not fall below the lower level and does not

rose above the upper level of the two-threshold comparator 11 in the presence of a busy signal in the line. If there is a speech signal in the line, then for some predetermined time T

the output signal of the detector 10 will necessarily go beyond the limits of the two-threshold comparator 11. The time interval T is determined by the time constant of the integrator 12. Over time T, the output

the voltage of the integrator 12 reaches the logic zero level necessary to reset the RS flip-flop 2 in the presence of a busy signal (for example, in 5-8 packages), and does not manage to reach this level when there is a speech signal. Those. the constant integrator T is selected from the condition

T (5 - 8) ge

where T3 is the period of the signal bursts. If there is no signal from the line, the block 13 of the absence of a message after a certain time changes the level of the output logic signal to zero

(as a block 13, a delayed level comparator may be used). Thus, at the output of circuit AND 14, a logic zero level appears, by which the RS trigger 2 is reset.

Thus, the proposed technical solution significantly simplifies the design of the answering machine (including the trip unit), reduces the number of control relays and increases the reliability of the trip.

Claims (1)

The claims An automatic telephone transponder comprising a call signal conversion unit, a response unit, a message recording unit, a shutdown unit, an amplifier, and a control relay, the opening contacts of which are connected between the input of the call signal conversion unit and the first output of the telephone line, and the making contact is connected to the output of the unit response and the input of the amplifier, the second output of the telephone line is connected to a common bus, and the shutdown unit contains a control unit for the absence of a message, the output of which is connected to the first input of the And element, characterized in that, in order to simplify the design and increase on. shutdown reliability, an RS-trigger is introduced, the installation input of which is connected to the output of the call signal conversion unit, the reset input is connected to the output of the shutdown unit, and the output of the RS-trigger is with a control relay, the closing contact of which is also connected to the input of the message recording unit, and the shutdown unit comprises a series-connected amplifier, a detector. a two-threshold comparator and integrator, the input of the no-message control unit is also connected to the amplifier input, and the integrator output is connected to the second input of the And element. Moreover, the output of the And element is the output of the shutdown unit.