DE2732532C2 - Telephone set for single and double used subscriber lines - Google Patents

Description

Object of the invention

The aim of the invention is to remedy the deficiencies outlined to overcome the known circuits and, moreover, by multiple use of the used Components to find a cost-effective solution. At the same time, in the interest of simplified storage and high availability when troubleshooting and reconnecting a universal telephone device be created, which at no additional cost and without loss of utility value special telephone terminals at the point of use easily from single to double-used subscriber lines or vice versa can be converted.

Explain the essence of the invention

The invention has the object of providing a telephone set to create the subscriber lines used in single and double use without additional Structural units can be operated, the function of an alternating current generator operating at high levels and the ringing is guaranteed with simple means as well as the operating voltage for subsequent electronic Provides assemblies without restricting the usable cable length. There are the disadvantages

known solutions that require an interconnection of separate units - common switch and electronic apparatus circuit - go out, eliminate. The disadvantages of such solutions, apart from the increased construction element expenditure, mainly consist in that the usable line length is restricted and the necessary active components cause distortion lead, whereby the transmission quality as well as the connection of further electronic assemblies for corresponding additional functions are restricted or impaired.

The invention is based on a transistor receiving amplifier circuit which is known in principle and whose supply happens via the o / fc wires of the connecting cable, The latter for reasons of polarity independence via a rectifier arrangement in Graetz circuit is turned on. When operated on subscriber connections that are used twice and are differentiated by polarity are the diodes lying in the direction of flow and preferably via pluggable bridges when the polarity is reversed solved by removing the mentioned bridges from the circuit.

For those due to the universal use In In each case, there is an alarm-capacitor combination arranged behind the diodes makes a so-called Rufentladeschalter necessary, whose function according to the invention taken over by the amplifier port, which can be switched over favorably for this purpose will.

30th

Embodiment

With reference to in the accompanying drawings, F1 g. i and Fig. 2, illustrated embodiments is intended to Invention will be explained in more detail.

The Flg. 1 shows the circuit of a telephone operator station. The circuit consists of a Graetz rectifier circuit, to the fork switch contacts, number switch contacts and the alarm clock arrangement connect.

The actual hybrid circuit consists of a resistor network Λ 2, Λ 3 and a line simulation Λ4, RS, CT. The microphone Mi is located in the bridge branch, preferably a stable one that works on a piezoceramic or dynamic basis.

The bridge circuit is followed by the amplifier transistor Π, which is in series with a transistor Tl , which is connected as an inductance.

The diodes of the Graetz-Glelchrlchterschaltung Dl, Dl, D3, DA make the circuit polarity independent with single use, with double use the diodes Dl, Z) 3 are switched off by removing the bridges Bl, Bl. The diodes Dl, DA form a switch for the call and the conversation state, whereby the polarity of the exchange line supply voltage is used as a criterion.

With single and double utilization, the capacitor C1 is charged when a call arrives. Since its discharge via the diodes locked is not possible, it is discharged through a Rufentladeschalter consisting of transistor Tl with R 6, R. 8 The diode DS causes the transistor Π to be switched through for one half-wave of the call and blocked for the other half-wave of the call. In series with the transistor Tl connected transistor Tl forms with the components CA, R9, RIO an inductance determines the Entladezelt of the capacitor Cl and dimensioned such that it is adapted to the frequency of the ringing current.

By appropriately switching the transistor Π with contacts of the hook switch GU 1 and GUl of the telephone set, the circuit is transferred to the known set of apparatus and switched on by simultaneous actuation of GU3 of the handset Fe when the handset is lifted.

In F1 g. 2 A circuit variant for ringer is shown. The alarm clock is replaced by a resistor Λ 13. The transistor Tl is consisting of Cl, C9, ClO, All and R 12, connected, so that this transistor operates as a positive feedback network both Rufentladeschalter as well as Tonrufoszillator. The decoupling of the ringing tone and the audio alternating voltage takes place via R 14 and CS. After lifting the handset, the ringer circuit is again transferred to the known apparatus circuit with the contacts of the hook switch GUl and GUl of the telephone set.

DS Reference number away = Wires of the connection line Dl ... = Diodes Bl, Bl ClO = Detachable bridges Wk RIA = Alarm clock Cl ... .GU3 = Capacitors Rl ... = Resistances GUl .. = Contacts of the hook switch Tl, Tl = Transistors Wed = Microphone Fe = Remote listener For this purpose 2 sheets of drawings

Claims (2)

Patent claims: 1. Ferrissprechapparateschaltung for single and double used subscriber connection lines, preferably for devices with transformerless hybrid circuit, which contain a transistorized receiving amplifier in series with a transistor connected as an inductance and where a full-wave rectifier is arranged in front of the device circuit for the purpose of independence from the polarity of the supply current, in which at Double use the diodes lying in the forward direction when the voltage is reversed are switched off via detachable bridges, characterized in that in the rest position the base of the amplifier transistor (7 "1) via a contact (GUI) of the hook switch on the wire of the input diodes (oil; Dl) Subscriber line is and that this wire is connected to the emitter of the amplifier transistor (Tl) via a forward-biased diode (DS) and a resistor (RS) , the alarm combination between the connection point of the resistor (Ri) with the diode (DS) and the other wire of the subscriber connection line. 2. Telephone set according to claim 1, characterized in that a known, from resistors (Λ11; R 12) and capacitors (Ci; C9; ClO) existing positive feedback network between the connection point of the diode (DS) with the resistor (Ri) and is connected to the contact (GUT) of the Gabelurrnchaliers leading to the base of the amplifier transistor (Γ1) in the rest position, so that the alarm clock (Wk) is replaced by a resistor (Λ13). The invention relates to a circuit design for telephone sets, preferably with a transformerless Hybrid circuit when using a transistor receiving amplifier, with the telephone set optionally can be used on single or double used subscriber lines. Characteristics of the known technical solutions Existing technical solutions indicate the trend that apparatus circuits to an increasing extent can be realized without winding components. In addition, the use of higher quality Converter as well as the transmission quality by regulating the sending, receiving or listening back improved. In most cases, a Graetz circuit is used to achieve polarity independence used. With the considerable increase in the number of telephone subscribers and for reasons of economy Use of copper and economic use of investments wins twice Use of subscriber lines is considerably more important. The double use of the subscriber connection line takes place either in the Welse that one of the two calls is transmitted with carrier frequency or through Activation of a community changeover switch, which uses the polarity of the exchange voltage as a selection criterion used e.g. B. at tellelektronlschen / elektronlschen Two-way connections, see E. Phlllppow, Telecommunications, Volume 3, VEB Verlag Technik Berlin, 1969, Pp. 804/805. The diodes necessary for this as what before the apparatus circuit lead to the subsequent electronic Apparatus circuit to the technical problem that by the four diodes connected one behind the other the available voltage and then the maximum usable connecting cable length is reduced. The solution mentioned requires some electronic components Components for the implementation of the two-way connection and a further part for the electronic Apparatus circuit. Furthermore, a circuit arrangement for centrally stored slave stations is known which contains a transistor amplifier, a transformerless hybrid circuit and possibly a transistor choke. With it, an optimal operating voltage for the receiving amplifier and additional assemblies is provided by using the voltage drop at the collector resistor of the transistor of the receiving amplifier, see DE-OS 21 59 150.
The disadvantages of this circuit arrangement are its polarity dependency, which restricts the area of application, and an additional diode in the speech or transmission circuit, which limits the length of the connectable subscriber connection, since the use of operating voltage and the ability to control the speech circuit are directly related. In addition, the circuit arrangement can only be used for operation on subscriber lines that are used twice in conjunction with the aforementioned shared switch. This results from the asymmetrical structure of the circuit arrangement, as a result of which the required blocking attenuation is not achieved, and from the need for a call discharge switch for alternating current alarm clocks. Thus, the through the cascading. This circuit arrangement does not eliminate the disadvantages of diodes.