FI56463C - ANGLE CONNECTION AV SIGNALER FRAON SUBSCRIBER TELEPHONE LEVELING - Google Patents

Description

- _____ ANNOUNCEMENT r c A C

W (11) UTLÄGGN I NGSSKRIFT 56463 C (^ 5) Patent granted 10 01 1930 ι iCvV Patent meddelat V 'V (51) Kv.lk.' / Int.CI. * S 04- M 3/22 '' H 04 - Q 1/20 £ Q | ____ p | m 0 (11) Patent application - Pttentansttknlng 3522/70 (22) Hakemisptlvi - Ansöknlngsdtg 31.12.70 (23) Primary cloud— Glltlghettdag 31.12.70 (41) Become Public - Bllvlt offentllg 0 ^ 4.0Ö. 71

Patent and Registration Office (44) Date of issue and date of issue. -

Patent- och reglsterstyrelsen 'Ansttkan utiagd och uti.skriften publicerad 28.09.79 (32) (33) (31) Pyydetty etuoikeus — Begird prlorltet 03.02.70

Switzerland-Switzerland (CH) 1563/70 Proven-Styrkt (71) Zellweger Uster AG, CH-8610 Uster, Switzerland-Switzerland (CH) (72) Hans Hulsbergen, Wald, Switzerland-Switzerland (CH) (7 * 0 Leitzinger Oy (5 ^) Apparatus for separating and / or separating signals from a subscriber's telephone line - Anordning för avkoppling av signaler frän abonnentens telefonledning

The invention relates to an apparatus for separating and / or separating signals from a subscriber's telephone line.

In an automatic long-distance communication facility, different signals appear on the subscriber's telephone line, partly simultaneously and partly sequentially. Such signals are used to indicate, for example, the status of the line, i.e. whether the line is busy or not. The purpose of the other signals is to select the subscriber to be called and further the purpose of the other signals is to determine the call charge, etc.

For certain tasks, such as the periodic monitoring of the operation of a telecommunications facility or central processing unit, or the duration of connections made by the subscriber, monitoring and registration of calls and related calls, and in this case, etc., it is often desirable to distinguish at least one of these signals. from the subscriber's telephone line and / or be separated in such a way that it does not adversely affect the proper functioning of the telecommunications facility. As a result, the connection must be high-ohmic and / or as symmetrical as possible with respect to the impedance of the cable.

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Some of said signals do not differ in frequency or very little in frequency and, in addition, have a low frequency, for example 50 Hz and below. It is therefore a disadvantage that the separation of such signals on the basis of their frequency difference by means of resonant circuits can only be carried out at considerable cost and, at the same frequency, cannot be done at all.

The object of the invention is to avoid these drawbacks and to provide a device with which the problem of separating and / or separating signals from the subscriber's telephone line can be economically solved.

To achieve this object, the device according to the invention is characterized by a potential blood device galvanically connected to at least one subscriber's telephone line conductor via a low-pass filter, the output of which is connected via a frequency-selectable switching element to an output terminal with a busy or non-busy output signal. the output of which is connected, on the one hand, via a high-pass filter and / or a frequency-selectable switching element output terminal, using a transmission-controlled next switching element, to the next output terminal with a signal derived before the potential comparison, and from at least one series connection of the low-pass filter and the limit value device connected on the input side and connected to the potential comparator input on the output side.

An embodiment of the invention will now be described with reference to the accompanying drawings, in which Figure 1 shows a block diagram of a simple embodiment.

Figure 2 shows a block diagram of the following embodiment.

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Figure 3 shows a device inlet side of a block diagram.

Figure 4 shows the input side of the circuit diagram of Figure 3.

Before describing an embodiment of the invention, some situations in the telephone line of the calling subscriber or called subscriber are described below. It should be noted in this context that the telecommunication systems used today have a partially different nature. However, the method or apparatus described below for carrying it out can always be applied by a person skilled in the art to the parameters of the system in question.

A) Situations in the case of a calling subscriber AI) Unoccupied: in the case of an open loop, the potential between conductors a and b of the subscriber's telephone line is equal to the smv of the battery.

A2) Horn raised: This is a closed loop = busy, the potential between leads a and b of the subscriber's telephone line decreases to a certain value. Due to the symmetry of the wire and the symmetry of the battery voltage input across the supply bridge, the potential change in both conductors is equal and the potential changes in both conductors are opposite.

A3) Number dialing: Breaking the loop to the beat of the twisted numbers causes corresponding voltage fluctuations in the subscriber line between modes A1 and A2. These potential fluctuations occur, for example, at a frequency of about 8 to 12 Hz. These are called selection pulses.

A4) Call monitoring signal: The control panel outputs audio frequency pulses to the calling subscriber at a frequency of 400 Hz and in step with the ringing signals to the called subscriber.

A5) The called subscriber raises the earpiece: This gives the exchange the first rate pulse to be sent to the calling subscriber. This rate pulse may be a 50 Hz AC pulse applied simultaneously to the subscriber line. However, it can also be, for example, a 12 kHz or 16 kHz pulse applied to the subscriber's line symmetrically with respect to the ground. The duration of such a taxi pulse is, for example, 200 milliseconds.

4 S6463 A6) Call: Speech signals are audio frequencies and act in opposite directions on both conductors a and b.

A7) Ending a call: This happens when the calling subscriber lowers the earpiece. This causes the loop to open, i.e. the wire returns to the unoccupied state AI.

B Situations in the case of a caller

Bl) Not reserved: As in AI.

32) Incoming call: 25 or 50 Hz AC signal between conductors a and b. In this case, depending on the system, the signal may be in either conductor a or b or both conductors.

33) The called subscriber raises the earpiece: As a result, his subscriber line goes into the reserved space, point A2.

B4) Call: Box A5.

B5) Ending the call: The called subscriber lowers the earpiece, causing his cord to return to the unoccupied state, point Bl.

Figure 1 shows a block diagram of a simple embodiment, thus provided with an indicator of a busy state and / or a non-busy state and selection pulses. The conductors 1a or Ib have conductors a or b connected to the inputs 2a or 2a 'of a frequency-selective switching element 2 or 2', for example a low-pass filter 2 or 2 '. The cut-off frequency of the low-pass filter 2 or 2 'is preferably selected only so high that, in addition to long-lasting busy or non-busy modes, only the selection pulses due to the periodic loop openings pass, i.e. for example about 10 Hz. The potential corresponding to the open or closed loop acting in the conductors a and b is passed through said low-pass filters 2, 2 'to the inputs 5a and 5b of the potential comparator 5. It is further advantageous to connect a limit value device 3 between each low-pass filter 2 or 2 'and the inputs 5a or 5b of the potential comparator 5. The limit value of this limit value device is preferably selected so large that only potential fluctuations when the loop opens or closes. potential reference device.

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Due to the fluctuation of said potential, the output signal acting at the output 5c of the potential comparator 5 varies between two predetermined values, for example between the logistic signals 1 and 0. The output signal thus indicates an open or closed loop state or an unoccupied state and a reserved state, as well as selection pulses. These signals indicating the specific situation of the subscriber line 1 are thus separated from the subscriber line 1, but not separated from each other.

The separation of the signals indicating a charged or non-charged state can take place, for example, by means of the following frequency-selective switching element, for example a low-pass filter 22, which has a cut-off frequency of, for example, 1 Hz, so that it does not pass selection pulses. As a result, the output signal U1 is derived. from the output 5c of the potential comparator by a conductor 20 to the input 21 of this next low-pass filter 22. Thus, only logic signals 1 or 0, which indicate a charged or uncharged state, act at the output terminal 23.

Since the selection pulses can only occur in the busy state of the subscriber line, the output signal U £ corresponding to the selection pulses can be separated from the charging signal by a corresponding logic circuit. The output signal can be routed from the output 5c by a conductor 31 to, for example, the input 32 of the S1 AND gate 33. The second input 34 of the AND gate 33 is connected by a conductor 35 to an output terminal 23 from which a charge signal U 1 is applied. Thus, the AND gate 33 is connected to pass only in the busy situation, and thus any selection pulses that may occur in this situation will be passed through the AND gate 33. These logic signals Uit corresponding to the selection pulses are still available for use from the output interface 36.

Figure 2 shows a block diagram of a further embodiment of the invention. Here, the device is further provided not only for separating the signals U1 indicating the line status of the line and the signals Uw corresponding to the selection pulses, but also for ringing signals from the subscriber line. Reference is made here to what has been stated previously in the situation in Section B2. The ring signal is an alternating voltage whose frequency is above the cut-off frequency of the low-pass filter mentioned in Fig. 1, and thus the low-pass filters prevent their passage. The ringing signal is therefore separated from at least one conductor, for example conductor b, by an alternating current connection, for example by a capacitor 56o connected to conductor b, from the subscriber line 1.

The ring signal signal occurs on the line of the called subscriber only in an unoccupied situation. Therefore, the ring signal signal is conducted by the conductor U1 to the input k2 of the switching element U3. In addition, an output signal U, from the output terminal 23 of the low-pass filter 22, to the control input U5 is supplied to the switching element U3 by a conductor UU. In addition, the switching element U3 is selected

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that it switches through the output terminal 23 under the influence of an active signal to pass only in the unoccupied state of the subscriber line. For example, an AND-gate is used for this purpose. The signal U corresponding to the ring signal is thus obtained from the output U6 of the switching element 1 + 3.

In an analogous manner, other AC voltage signals present in the subscriber line, for example taxi pulses, can be separated from the subscriber line by an AC connection, for example a resonant circuit with a separate output connection.

The duration of booking situations for the subscriber's management can vary within wide limits.

The practical duration of the minimum charge situation T. however, is about min 1 second, which gives a maximum charge frequency f of about 1 Hz. The cut-off frequency of said next frequency-selectable switching element 22, which is, for example, a low-pass filter, is therefore suitable to take about 1 Hz.

From the output signal signal obtained by the potential comparison, the output signal U corresponding to the selection pulses can also be obtained so that the output signal acting at the output 5c of the potential comparator 5 is passed through a high-pass filter either via a controlled switching element 33 or directly to an output terminal 3. In this case, it is suitable to select a value between the frequency of the selection pulse and the maximum busy frequency f as the cut-off frequency of the high-pass filter.

In Figure 3 the input side of the device block diagram. This input side includes the connection to the subscriber line 1 via both conductors 1a and Ib and the associated low-pass filters S6463 met 2 and 2 ', limit value devices 3 and 3' and a potential comparator 5. The output signal of the potential comparator 5 is obtained from terminal 5c . The conductor 7, which acts as a common zero-potential busbar, is connected to the +20 V terminal of the supply battery.

Due to the conventional symmetrical supply of battery voltage to the subscriber line, the transition of the subscriber line from the uncharged state to the charged state and inversely from the charged state to the uncharged state in both conductors a and b due to potential fluctuations in opposite directions is observed. Of course, the alignment of the conductors a and b, «f, which depends on the input of the subscriber's line, has not been performed uniformly in the various remote communication networks. As can be seen from Fig. 3, these are symmetrical connection arrangements, in which one side of the connection system is connected by conductor 1a to conductor a and the other connection half by conductor Ib to conductor b.

Both limit value devices 3 and 3 'have a defined limit value which must be affected at their inputs 3a or 3a1, because at their output 4 or H1 the output potential or U4' varies by leaps and bounds. This limit value corresponds to the voltage U2 or U2 'required at the input 2a or 2a' of the low-pass filter 2 or 2 'for the operation of the trailing limit device. · If, in a given application, a change in charge causes a potential oscillation of at least 11 volts in both conductors a and b , then it is preferable to select the limit value of the limit value device 3 or 3 'so that the voltage value U2 or U2' required for the operation of the limit value device is in this case 11 volts. The magnitude of the limit value at the input of the limit value device 3 or 3 'is thus smaller due to the voltage drop in the low-pass filter 2 or 2 *.

The limit value device 3 or 3 'can be, for example, a directly connected amplifier circuit, which is dimensioned in a known manner so that its switching state changes when the limit value is reached at its input. In the device according to Fig. 3, the fluctuation of the potential occurring when the busy situation of the subscriber line changes together changes the output potential or by a jump.

Whether this abrupt change occurs at the output 4 of the limit value device 3 or at the output 4 'of the limit value device 3' depends on the selected na gain of the conductors a and b of the telecommunication network in relation to the input of the subscriber line. However, whenever the state of the subscriber's line changes from uncharged to busy or from busy to uncharged, a potential change to the output of the second limit value device is always obtained, while the output potential of the second limit value device does not change. Such an arrangement of the device ensures that, always according to the orientation of the conductors a and b, one of the two limit value devices remains invariably in a certain switching state, regardless of the charge situation.

Thus, there is always a constant, charge-independent operating potential at the output of the second limit value device in connection with a change in the charge status of the subscriber's line. The function of the potential comparator 5 is to express this change in potential, which unambiguously represents the reservation tone of the subscriber's line. The potential reference device can be, for example, a relay or a bistable electronic switch connected between the output terminals 4 and 4 'of the limit value devices 3 and 3'.

In order to keep the busy or non-busy situation-dependent signal unchanged in the event of a possible supply failure for at least another situation, it is expedient to equate the situation in which it should not change with the relay sleep state, i.e. the signal U leads, . via the rest contact of the relay to output U.

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Fig. 4 shows a circuit diagram of the embodiment of Fig. 3. In Fig. 4, the connection points and connection elements corresponding to Fig. 3 are denoted by the same reference numerals. Since other signals, for example AC voltage signals, are usually present in the state telephone line, the potential comparator 5 can be rendered insensitive to AC voltages by connecting a diode 8 or 8 'in front of the inputs 2a or 2a'. There is a rectification across said diodes 9 or 9 'in connection with said diodes and the resistors 9 or 2a' at each of the inputs 2a or 2a 'for any alternating voltages which may be present, which are converted into equally effective DC voltages. With respect to these DC voltages acting in the same direction, the potential comparator is insensitive. In order to also protect them against possible overvoltages in the lines of the subscriber's line, an overvoltage protection 10 or 10 * can preferably be provided in connection with each low-pass filter 2 or 2 '. In the embodiment according to Fig. 4, the limit value devices 3 or 3 * are formed in a known manner as directly connected amplifier connections. The potential reference device 5 is

Claims (2)

56463 A relay used in the embodiment of Fig. 4, the working contact of which connects a positive voltage to the output terminal 5c when there is a potential difference between the outputs 4 and 4 '. Device for separating and / or separating signals from a subscriber's telephone line, characterized by a potential comparator (5) galvanically connected to at least one conductor (a, b) of the subscriber's telephone line (1) via a low-pass filter (2; 2 '), the output (5c) of which is connected via a frequency selectable switching element (22) to an output terminal (23) having an output terminal corresponding to a busy state or a non-busy state (U 1), the output (5c) of which is connected on the one hand by a high-pass filter and / or a frequency select switch element (22) (U 1), using a next transmission element (33) controlled by its throughput, to the next output terminal (36), which is affected by a signal (U) corresponding to the dialing pulses of the subscriber's telephone line, from at least one limit device (3, 3 '). in a closed loop, the potential in the subscriber's line is derived before the potential comparison is performed, and at least one a series connection of a low-pass filter (2 or 2 ') and a limit value device (3 or 3') connected on the input side (1a, 1b) to the conductor (a or b) of the subscriber line (1) and connected on the output side to the input of the potential reference device (5) (5a or 5b). Device according to Claim 1, characterized by an AC voltage connection (40) s connected to the at least one conductor (a, b) and / or a frequency-selective device for separating AC voltage signals (signaling, rate, call monitoring) from these conductors (a, b) and connected in series with it. an adjustable switching element (43), to the control input (45) of which at least one output signal (U 1) derived from the output voltage (U 1) of the potential comparator (5) is applied.