SU1374445A1 - Device for receiving call signals for electronic exchanges - Google Patents

Abstract

The invention relates to wired telephone communications and extends functionality by providing reception of a long distance call signal. The device contains a matching unit 1, an optocoupler switch 2, NOT 3, 10, and 12, a shift register 4, a counter 5, And 6, 11, 13, and 14, triggers 7 and 9, a driver 8. 1 Il.

Description

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The invention relates to wired telephone communications and can be used in control nodes of electronic automatic telephone exchanges.

The purpose of the invention is to enhance the functionality by providing reception of a long-distance call signal.

The drawing shows a block diagram of a call signal receiving device for electronic telephone exchanges.

The call signal receiving device for electronic telephone stations contains a matching unit 1, a rptron-15 switch 2, the first element is NOT 3j shift register 4, counter 5, first

the element And 6, the first trigger 7, the driver 8, the second trigger 9, the second element is NOT 10, the second element is And 11, the third element is NOT 12, the third element is And 13, the fourth element is And 14,

The device receiving the call signal for electronic telephone stations works as follows

In the absence of a call on the connecting line, the third element And 13 is open and, in cycles of 12, the trigger 7 is set to the zero state 5trig20

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If the call is a long-distance call, then at the moment when the signal arrives at the input of the And 11 element coming from the And 6 element, the next call will always be present at its second input (therefore, the required number of counted clock pulses in the counter 5 ), and the trigger 7 will be permanently set to the long distance call state.

If the call is normal, then at the moment of appearance of the signal at the output of the element And 6 at the input of the element 11, the call signal from shift register 4 will not be received, since the pause between the regular call sending is three times larger

Ger 9 is cleared. The shift register is 4 for more than the long-distance one. In this case

filled with zero, the output of the optocoupler switch 2 unit. When an ac current signal arrives through the line, the voltage of the latter through the matching unit 1 is fed to the input of the optocoupler switch 2. The zero level from the output of the optocoupler switch 2 is fed through the element NO 3 to the input of the shift register 4. In case the duration of the signal is longer than the delay time of the shift register 4, the signal from its output through the element NOT 12 closes the element AND 13 O After the end of the call, the driver 8 is triggered, which includes a trigger 9 allowing the passage of T1 clock pulses to the counter input 5 and blocking the passage of T2 to the setup input of the trigger 7. After counting a certain number of pulses, selected from the condition that the counting time was slightly longer than the pause time between the call sends, at the output of the element nta AND 6 a signal appears, which is fed to the inputs of the elements 11 and 14. By the time the signal is turned on

At the output of element AND 6, at the second input of the element-And 11, there is a signal of the second dressing of the call, which turns on trigger 7, T2 through pulse And element 14, trigger 9 is set to the initial

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cycles of T1 in the counter 5 and wrapped it through the element NOT 10

After the end of the second call sprinkling, trigger 9 is turned on again and the process is repeated.

If the call is a long-distance call, then at the moment when the signal arrives at the input of the And 11 element coming from the And 6 element, the next call will always be present at its second input (this is the basis of the required number of counted clock pulses in the counter 5), and trigger 7 will be permanently set to the long distance call state.

If the call is normal, then at the moment of appearance of the signal at the output of the element And 6 at the input of the element 11, the call signal from shift register 4 will not be received, since the pause between the regular call sending is three times larger

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through the element 14 on the cycle T2, the trigger 9 is first set to zero, and then the trigger 7,

After the arrival of the last call, the scheme works in the same way as described for the case of a normal call, and the trigger 7 is set to the zero state,

Claims (1)

Invention Formula A device for receiving a call signal for electronic telephone stantium containing a serially connected matching unit, an optocoupler switch, the first element NOT and the shift register, and also a counter whose outputs are connected to the inputs of the first element I, the first trigger, the combined counting inputs of the shift register and the counter are the first clock input of a call signal reception device for electronic telephone exchanges, characterized in that., in order to extend the functionality by providing reception igkap a long distance call, put the second, third and fourth AND gates, the second element is not sequentially soedinen313744454. the second trigger, to the second input of the third element I, the output of which is connected to the permitting, to the third input of which is the counter input of the counter, and the third element of the second clock input of the device NOT whose output is connected to the input of receiving call signals for the electron - reset the counter, and through the third e-nk telephone exchanges, an I-ment is connected - to the reset input of the first trig-first input of the fourth element I, to Hera, to the installation input of which the second input of which is connected to the second The control unit of the second element I is connected the first input of which is connected to. the output of the OD of the first element is And, and the output of the fourth shift register and the input of the Formed element And is connected to the input of the pad, and through the third element is NOT a reset of the second trigger.