DK144109B

DK144109B - TRANSMISSION CONNECTOR FOR TRANSFER OF CORRESPONDING TRIGGRAPHIC SIGNS

Info

Publication number: DK144109B
Application number: DK380372AA
Authority: DK
Inventors: N Skobranek
Original assignee: Siemens Ag
Priority date: 1971-08-02
Filing date: 1972-08-01
Publication date: 1981-12-07
Also published as: CA973804A; IT963475B; JPS4825403A; AT323246B; NL7209920A; BR7205196D0; CH542556A; ZA724772B; BE787088A; FR2148210B1; LU65824A1; DK144109C; AU4450472A; JPS5238683B2; DE2138576A1; FR2148210A1; GB1363553A; DE2138576C3; DE2138576B2; AU459938B2

Description

(19) DANMARK (^) ir m) (12) FREMLÆGGELSESSKRIFT od 14Μ09Β(19) DENMARK (^) ir m) (12) PUBLICATION MANUAL od 14Μ09Β

DIREKTORATET FOR PATENT- OG VAREMÆRKEVÆSENETDIRECTORATE OF THE PATENT AND TRADEMARKET SYSTEM

' " ' ——I I II t Μ I II . I Ml I J .1"') ) III ........ i |............ I — (21) Ansøgning nr. 3803/72 (51) IntCI.3 H 04 L 2$/20 (22) Indleveringsdag 1· aug. 1972 (24) Løbedag 1 . aug. 1972 (41) Aim. tilgængelig 3· feb. 1973 (44) Fremlagt 7· dec. 1981 (86) International ansøgning nr. - (86) International indleveringsdag - (85) Videreførelsesdag - (62) Stamansøgning nr. -"" ——II II t Μ I II. I Ml IJ .1 "')) III ........ i | ............ I - (21) Application No. 3803/72 (51) IntCI.3 H 04 L 2 $ / 20 (22) Filing Day 1 · Aug. 1972 (24) Race day 1. August 1972 (41) Aim. available Feb 3 1973 (44) Posted 7 Dec. 1981 (86) International Application No. - (86) International Filing Day - (85) Continuation Day - (62) Master Application No. -

(30) Prioritet 2. aug. 1971, 2138576, DE(30) Priority Aug 2 1971, 2138576, DE

(71) Ansøger SIEMENS AKTIENGESELLSCHAFT, Berlin und Muenchen, 8 Muenchen 2, DE.(71) Applicant SIEMENS AKTIENGESELLSCHAFT, Berlin and Munich, 8 Munich 2, DE.

(72) Opfinder Norbert Skobranek, DE.(72) Inventor Norbert Skobranek, DE.

(74) Fuldmægtig Internationalt Patent-Bureau.(74) International Patent Bureau.

-...... ~ ' " - '* ' " 11 1 1""'< 1 f" ....... 1 -1' ' ' (54) Omsætterkobling til overføring af jævnstrømstelegrafitegn.-...... ~ '"-' * '" 11 1 1 ""' <1 f "....... 1 -1 '' '(54) Converter coupling for transmission of DC telegraphs.

Opfindelsen angår en omsætterkobling til overføring af jævnstrøms-telegra-' fitegn mellem en envejs- og en tovejskobling med en modtage- og en senjleindret-ning, hvorved den over en abonnentledning gående liniestrøm kan afbrydes af modtageindretningen i rytme af de ankommende telegrafitegn, som skal sendes til abonnenten.BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to a converter coupling for transferring DC telegraphic signage between a one-way and a two-way coupling with a receiving and a senel device, whereby the line current passing through a subscriber line can be interrupted by the receiving device in rhythm of the arriving telegraph signs. sent to the subscriber.

I fjernskriveformidlings- og fjernskriveoverføringsteknikken kræves der i stort omfang totråds-tastkoblinger. Som det mest kendte anvendelsestilfælde hen-PQ vises der blot til enkeltstrøm-dobbeltstrømomsætteren, men anvendelsen af disse 3^ koblinger er ikke begrænset til dette anvendelsestilfælde.Two-wire key couplings are largely required in long-distance transmission and long-distance transmission technology. As the most well-known use case PQ is shown only to the single current dual current converter, but the use of these 3 ^ couplings is not limited to this use case.

O ...Oh ...

(— De kendte tilslutningskoblinger lader sig ifølge deres funktion opdele 1 -3" to grupper, hvorved som kriterium anvendes tastningen af abonnenttilslutningsled- r~ ningen.Ved den ene gruppe bliver abonnenttilslutningsledningen ved sending i ret- *(- The known connection couplings, according to their function, can be divided into 1 -3 "two groups, whereby as a criterion the testing of the subscriber connection line is used. In one group, the subscriber connection line is transmitted in straight line *

OISLAND

2 144109 ning til abonnenten gjort strømløs ved afbrydelse til styring af den ved abonnenten forhåndenværende modtagemagnet i fjernskrivemaskinen.Derfor taler man om koblinger med afbrydelsestastning.Ved den anden gruppe bliver abonnenttilslutnings-ledningen ved sending i retning mod abonnenten kortsluttet. I denne forbindelse taler man om koblinger med kortslutningstastning.2 144109 power to the subscriber is rendered powerless by interrupting control of the receiver magnet provided by the subscriber in the remote typewriter. This is why interconnection key couplings are spoken. In the second group, the subscriber connection line is transmitted in the direction towards the subscriber. In this connection, we talk about short-circuit key couplings.

På tegningen vises de to principper på grundlag af et eksempel.The drawing shows the two principles on the basis of an example.

Fig. 1 viser en kobling, som arbejder ifølge den såkaldte afbrydeisestastning. Det antages, at de en forbindelsesgennemkobling forudgående processer, såsom opkald, valgopfordring, valg og gennemkobling mellem den kaldende og kaldte abonnent allerede er afsluttet.FIG. 1 shows a coupling which operates according to the so-called disconnection key. It is assumed that a prior connection process such as call, call request, call and call forwarding between the calling and called subscribers is already completed.

Hvis kontakten b af et modtagerrelæ B befinder sig i den viste position svarende til stoppolaritet, går der en strøm over ledere al og bl af abonnenttilslutningskoblingen AnL fra den positive til negative pol af telegrafi-batteriet TB, hvilken strøm aktiverer modtagemagneten EM på abonnentpladsen TI. Egenkapaciteten af abonnenttilslutningsledningen oplades svarende til den påtrykte spænding. Ved modtagelsen af et skridt svarende til startpolaritet over fjernledningen FL omstyres kontakten af modtagerrelæet B, og derved afbrydes abonnenttilslutningsledningen AnL. For at undgå en påvirkning af senderelæet A under omstyringen af kontakten b, forefindes en holdemodstand Rh, over hvilken der også i det tilfælde, hvor abonnenttilslutningsledningen er afbrudt, går en aktiveringsstrøm til en første vikling AI af senderelæet. En ulempe ved denne kobling ligger i, at afladningen af abonnenttilslutningsledningen, som blev afbrudt ved kontaktens omstyring, udelukkende fremkommer over abonnentpladsen TI. Dette betyder, at der ved afbrydelsesprocesser, især ved lange abonnenttilslutningsledninger, optræder betydelige forvrængninger ved modtagelsen af fjernskrivetegn. Ydelsen af tilslutningskoblinger, som arbejder efter afbrydelsestastningsprincippet, frembyder altså først og fremmest fordele ved tilslutningsledninger af ringe længde.If the switch b of a receiver relay B is in the position shown corresponding to stop polarity, a current passes through conductors all and b1 of the subscriber connection connection AnL from the positive to negative pole of the telegraphic battery TB, which current activates the receiving magnet EM at the subscriber space T1. The intrinsic capacity of the subscriber connection line is charged according to the voltage applied. Upon receiving a step corresponding to the starting polarity over the remote conduit FL, the contact is switched by the receiver relay B, thereby interrupting the subscriber connection conduit AnL. In order to avoid influencing the transmitter relay A during the switching of the switch b, there is a holding resistor Rh, above which, even in the case where the subscriber connection line is disconnected, an activation current goes to a first winding AI of the transmitter relay. A disadvantage of this coupling is that the discharge of the subscriber connection line, which was interrupted by the switching of the contact, appears exclusively over the subscriber space T1. This means that during interruption processes, especially with long subscriber connection lines, significant distortions occur when receiving remote writing characters. Thus, the provision of connection couplings, which operate according to the interrupt test principle, presents first and foremost the advantages of small length connection lines.

En efter kortslutningstastningsprincippet arbejdende kobling er vist i fig.A coupling operating according to the short-circuit keying principle is shown in FIG.

2. Der gås atter ud fra, at forudgående processer vedrørende forbindelsesgennem-koblingen er afsluttet, og at der over fjernledningen FL modtages stoppolaritet. Kontakten b af modtagerrelæet B er i den viste position svarende til stoppolaritet, således at der atter går strøm over abonnenttilslutningen AnL fra den positive til den negative pol af telegrafibatteriet TB. Ligesom i koblingen ifølge fig. 1 er også her abonnenttilslutningsledningen opladet svarende til den påtrykte spænding. I koblingen ifølge fig. 2 bliver i modsætning til den i fig. 1 viste kobling ved hjælp af et til startpolaritet svarende skridt, som indtræffer over fjernledningen FL og den betjente kontakt b abonnenttiislutningsledningen og dermed modtagemagneten gjort strømløs ikke ved en afbrydelse, men ved en kortslutning. Denne kobling frembyder over for den i fig. 1 beskrevne kobling 3 144109 den fordel, at afladningen af abonnenttilslutningsledningen som følge af kortslutningen sker med en mindre tidskonstant, og at tidskonstanten er lige stor for strømstigning og strømfald, hvorved det er forudsat, at den indre modstand af sendekoblingen uden hensyntagen til ledningskompletteringsmodstanden RL er lille i forhold til den samlede modstand af abonnenteløjfen. En tastkobling, som arbejder efter dette princip, egner sig altså med fordel til relativt lange abonnenttilslutningsledninger.2. It is again assumed that prior processes relating to the connection through connection have been completed and that stop polarity is received over the remote conduit FL. The contact b of the receiver relay B is in the position shown corresponding to stop polarity, so that current again goes over the subscriber connection AnL from the positive to the negative pole of the telegraphic battery TB. As in the coupling according to FIG. 1, here too, the subscriber connection line is charged corresponding to the voltage applied. In the coupling according to FIG. 2, in contrast to that of FIG. 1, by means of a step similar to the starting polarity, which occurs over the remote conduit FL and the operated contact b the subscriber connection conduit and thus the receiving magnet is rendered powerless not by a disconnection but by a short circuit. This coupling presents to that of FIG. 1 described in connection 3 144109 the advantage that the discharge of the subscriber connection line as a result of the short circuit occurs with a smaller time constant and that the time constant is equal for current rise and decrease, provided that the internal resistance of the transmitting coupling without regard to the cable completion resistance RL is small relative to the total resistance of the subscriber loop. A key coupling that works according to this principle is thus advantageous for relatively long subscriber connection lines.

En efter kortslutningstastningsprincippet arbejdende tilslutningskobling har dog ved korte strækninger mellem abonnentpladsen og tilslutningskoblingen, hor den induktive indvirkning fra modtagemagneten på abonnentpladsen overvejer den ka« pacitive indvirkning fra ledningen, fer så vidt en ugunstig egenskab, nemlig at der på grund af den manglede ledningskapacitet ikke optræder nogen strømv ending, dvs. der optræder ikke noget såkaldt undersving af strømkurven i modtageraagneten.I mange anvendelsestilfælde er dette undersving af strømkurven dog netop nødvendigt for at fjerne remanensen i modtagemagneten.However, for short distances between the subscriber space and the connection coupling, a short-circuit keying principle operates when the inductive effect of the receiver magnet on the subscriber site considers the capacitive effect of the cable, so far as an unfavorable characteristic, namely that due to the lack of conductive capacity, any current ending, ie there is no so-called undershoot of the current curve in the receiver magnet. In many applications, however, this sub-curve of the current curve is precisely necessary to remove the residue in the receiver magnet.

Der er for nylig blevet foreslået en kobling, hvor liniestrømmen ikke kan indstilles over en ledningskompletteringsmodstand, som er individuelt indstillelig, men derimod ved hjælp af en automatisk reguleringsindretning, f.eks. en elektronisk styret modstand, stadig holdes på en konstant værdi, f.eks. 40mA. Denne automatiske reguleringsindretning kan enten erstatte den traditionelle ledningskompletteringsmodstand eller med koblingsteknisk fordel indkobles mellem telegrafibatteriet og kontakten, som styrer tilslutnings ledningen. Bi ifølge det sidstnævnte princip opbygget kobling har dog den overføringstekniske ulempe,at tidskonstanten ved ekstremt kort lednings længde bliver så stor for strømfaldet i modtagemagneten, at ankeret af modtagemagneten ikke mere falder sikkert.Recently, a coupling has been proposed in which the line current cannot be set over an individually adjustable line completion resistor, but by means of an automatic control device, e.g. an electronically controlled resistor, still held at a constant value, e.g. 40mA. This automatic control device can either replace the traditional line completion resistor or with coupling technical advantage be coupled between the telegraphic battery and the switch which controls the connection line. However, in accordance with the latter principle, coupling built-up has the disadvantage of transmission technology that the time constant at extremely short wire length becomes so large for the current drop in the receiving magnet that the anchor of the receiving magnet no longer falls securely.

Opfindelsens formål er at tilvejebringe en kobling til tastning af totråds-enkeltstrømkredse, hvor disse ulemper ikke optræder. Ifølge opfindelsen opnås dette ved, at der mellem abonnentledningens to ledere findes en ekstrakobling, som ved afbrydelse af den over abonnentledningen gående liniestrøm kobles til abonnentledningen ved hjælp af koblemidler i modtageindretning, at ekstrakoblingen indeholder en diode og et parallelt med dioden koblet RC-led og en parallelt med kondensatoren i RC-leddet koblet yderligere modstand, og at dioden i ekstrakoblingen i det tilfælde, at den af abonnentledningen og en modtagemagnet bestående indretning er kapacitiv (lang abonnentladning) ar gennemtrængelig for den efter afbrydelsen af linie·trømmtn ovar abonnentladningen giende kapscitiva afladt-strøm, og i dat tilfalda, at danne indretning er induktiv (kort abonnentladning) er sparret for den som følge af den induktive virkning af modtagamagnetan ovar abonnentledningen gående strøm.The object of the invention is to provide a coupling for sensing two-wire single current circuits where these disadvantages do not occur. According to the invention, this is achieved by providing an additional coupling between the two conductors of the subscriber line which, when disconnecting the line current passing over the subscriber line, is connected to the subscriber line by means of coupling means in the receiving device, the auxiliary coupling contains a diode and a dc coupled RC parallel to the diode. an additional resistor coupled in parallel with the capacitor in the RC joint, and the diode in the auxiliary coupling in the case that the subscriber line and a receiver magnet device is capacitive (long subscriber charge) are permeable to the capacitive capacitance produced after the disconnection of the line discharged current, and in that case, forming device is inductive (short subscriber charge) is spared for it due to the inductive effect of receiving magneton the subscriber line oscillates current.

Koblingen ifølge opfindelsen kan anvendes såvel i tilslutningskoblinger med 144109 4 traditionel liniestrømindstilling over ledningskompletteringsmodstanden henholdsvis dens elektroniske balanceringskreds, som også i tilslutningskoblinger med automatisk liniestrømindstilling ved hjælp af en reguleringsindretning ved spændingskilden.The coupling according to the invention can be used both in connection couplings with traditional line current setting over the line completion resistor and its electronic balancing circuit, as well as in connection couplings with automatic line current setting by means of a control device at the voltage source.

Opfindelsens enkeltheder beskrives i det følgende på grundlag af nogle udførelseseksempler. Som eksempel på tastningen af en totråds-enkeltstrømkreds er der vist en enkeltstrøm-dobbeltstrømomsætterkobling, idet fig. 3 viser en kobling, hvor liniestrømindstillingen sker ved hjælp af en ledningskompletteringsmods tand, fig. 4 viser en kobling, hvor størrelsen af liniestrømmen indstilles automatisk, og fig. 5 sluttelig en inden for opfindelsens rammer liggende yderligere udførelsesform for koblingen ifølge fig. 4.The details of the invention are described below on the basis of some exemplary embodiments. As an example of the sensing of a two-wire single current circuit, a single current dual current converter coupling is shown, fig. Fig. 3 shows a coupling in which the line current setting is done by means of a wire completion mode tooth; 4 shows a coupling in which the magnitude of the line current is automatically adjusted, and fig. 5 is a further embodiment of the coupling according to FIG. 4th

Den i fig. 3 viste kobling er over ledere al og bl af en totrådabonnent-tilslutningsledning AnL, som udgør totråds-enkeIts trømkreds en, forbundet med en abonnentplads TI, hvoraf kun sendekontakten sk og modtagemagneten EM er vist. Indstillingen af liniestrømmen udføres på kendt måde gennem den individuelle balancering af ledningskompletteringsmodstanden RL. Ledningskompletteringsmodstanden RL kan dog også erstattes af en egnet automatisk reguleringsindretning K, f.eks. en elektronisk modstand. I fig. 3 er dette antydet ved den skraveret vist indretning K. Som firtråd-strømkreds vises fjernledningen FL, hvorover koblingen AS over kontakten a af en sendeindretning AI, All afgiver dobbeltstrømtegn. Omvendt udnyttes dobbeltstrømtegn, som indtræffer over fjernledningen FL, ved hjælp af en tastningsindretning, der kan være en modtageindretning, f.eks. en elektronisk telegra-fisignaloverfører, således at der afgives enkeltstrømtegn i retning mod abonnenten. Ifølge opfindelsen har tastningsindretningen i dette tilfælde to adskilte skiftevis fungerede kontakter bkl og bk2, af hvilke den første er indkoblet i og afbryder den til en abonnent førende ledning, nemlig lederen bl, medens den anden bevirker tilslutning af ekstrakoblingen Z på totråds-enkeltstrømkredsen.The FIG. 3 is shown over conductors all and b1 of a two-wire subscriber connection line AnL, which constitutes the two-wire single circuit of one, connected to a subscriber space T1, of which only the transmitting contact sk and the receiving magnet EM are shown. The adjustment of the line current is carried out in a known manner through the individual balancing of the line completion resistor RL. However, the wire replenishing resistor RL can also be replaced by a suitable automatic control device K, e.g. an electronic resistor. In FIG. 3, this is indicated by the shaded device shown K. As a four-wire circuit, the remote line FL is shown, over which the coupling AS over the contact a of a transmitting device AI, All gives double current sign. Conversely, double current signs occurring over the remote line FL are utilized by a sensing device which may be a receiving device, e.g. an electronic telegra fish signal transmitter so that single current signals are delivered in the direction towards the subscriber. According to the invention, the sensing device in this case has two separate alternating contacts bk1 and bk2, the first of which is connected in and disconnects it to a subscriber leading line, namely the conductor b1, while the second causes the connection of the auxiliary connection Z to the two-wire single current circuit.

Til forklaring af en omsætteproces går man ud fra, at tastningsindretningen B er aktiveret med stoppolaritet, som vist i fig. 3. I dette tilfælde går der en strøm fra den positive pol af spændingskilden TB i tilslutningskoblingen AS over den første kontakt bkl, lederen bl af abonnenttiislutningsledningen AnL, modtagemagneten EM, den sluttede sendekontakt sk, lederen al af abonnenttilslutningsledningen anL, ledningskompletteringsmodstanden RL henholdsvis reguleringsindretningen K og sendeindretningen AI til den negative pol af spændingskilden. Samtidig går der en strøm fra positiv pol af spændingskilden over balanceringsmodstanden RN og sendekoblingen All til den negative pol af spændingskilden. Abonnenttilslutningsledningen er opladet svarende til den påtrykte spænding. Ved indtrædel- 144109 5 sen af et skridt med startpolaritet over fjernledningen FL omstyres kontakterneFor explanation of a reaction process, it is assumed that the sensing device B is activated with stop polarity, as shown in FIG. 3. In this case, a current from the positive pole of the voltage source TB in the connection circuit AS passes over the first contact bk1, the conductor b1 of the subscriber connection line AnL, the receiving magnet EM, the closed transmit switch sk, the conductor all of the subscriber connection line anL, the cable completion resistor RL and the control device K, respectively. and transmitting device AI to the negative pole of the voltage source. At the same time, a current from positive pole of the voltage source passes over the balancing resistor RN and transmitter coupling All to the negative pole of the voltage source. The subscriber connection cable is charged according to the voltage applied. Upon entering a step of starting polarity over the remote conduit FL, the contacts are diverted

BB

bkl og bk2 af tastningsindretningeny£ Dermed frakobler den første kontakt bkl den til abonnenten førende leder bl af tilslutnings ledningen AnL, medens den anden kontakt bk2 over ekstrakoblingen Z samtidigt ojfygger en kortslutningskreds for totråds-enkeltstrømkredsen, dvs. til abonnenttiIslutningsledningen AnL. Over dioden D i ekstrakoblingen Z står nu en meget lavohmsk afladningsvej for ledningskapacitet til rådighed. Over for en kobling, som arbejder efter kortslutningstastningsprincippet, er modstanden af denne kortslutningsvej kun forhøjet ubetydelig, nemlig med et diodespændingsfald.bk1 and bk2 of the sensing device new £ Thus, the first contact bk1 disconnects the conductor leading to the subscriber b1 of the connection line AnL, while the second contact bk2 over the auxiliary connection Z simultaneously simultaneously a short circuit for the two-wire single current circuit, ie. to the subscriber connection line NOTE. Above the diode D in the auxiliary coupling Z, a very low ohmic discharge path for conduction capacity is now available. In the case of a coupling which operates according to the short-circuit testing principle, the resistance of this short-circuit path is only slightly increased, namely a diode voltage drop.

Koblingen ifølge opfindelsen opfylder altså de stillede krav, især for lange tilslutningsledninger.The coupling according to the invention thus meets the requirements, especially for long connection lines.

For det tilfælde, at den mellem abonnentpladsen Ti og tilslutningskoblingen AS forløbende abonnenttiislutningsledning AnL ikke når op på en bestemt længde, overvejer den induktive indvirkning fra modtagemagneten gM den kapacitive indvirkning fra abonnettiIslutningsledningen. Dette betyder, at den samlede overførings-vej antager induktiv karakter. Ifølge opfindelsen indeholder ekstrakoblingen Z et netværk, som er koblet parallelt med dioden D, og dette netværk består i udførelseseksemplet af et RC-led med en kondensator Cl og en modstand RI. Fpr den som følge af den induktive indvirkning fra modtagemagneten EM over abonnenttiislutningsledningen AnL gående strøm, som er rettet modsat afladestrømmen, er dioden D i ekstrakoblingen Z spærret. Derigennem bliver kondensatoren Cl af RC»ledet, som er koblet parallel med dioden D opladet af denne strøm. Efter afklingen af denne strøm aflades kondensatoren Cl nu over modtagemagneten EM, hvilket fører til, at remanensen i modtagemagneten fjernes og ankeret af modtagemagneten falder fra tidsmæssigt eksakt. Koblingen ifølge opfindelsen frembyder altså ved korte abonnenttilslutningsledninger alle fordele ved en efter afbrydelsestastningsprincippet arbejdende kobling.In the event that the subscriber connection line AnL extending between the subscriber space Ti and the connection coupling AS does not reach a certain length, the inductive effect of the receiving magnet gM considers the capacitive effect of the subscriber connection line. This means that the overall transfer path assumes inductive character. According to the invention, the auxiliary coupling Z contains a network which is connected in parallel with the diode D, and this network consists in the exemplary embodiment of an RC link with a capacitor C1 and a resistor R1. Fpr it due to the inductive action of the receiving magnet EM over the subscriber connection line AC current directed to the discharge current, the diode D in the auxiliary coupling Z is blocked. Thereby, the capacitor C1 is led by the RC, which is connected in parallel with the diode D by this current. After clearing this current, the capacitor C1 is now discharged over the receiving magnet EM, which causes the residue in the receiving magnet to be removed and the anchor of the receiving magnet to fall from the exact time. Thus, the coupling according to the invention offers, by short subscriber connection lines, all the advantages of a coupling operating according to the interrupt keying principle.

Ifølge opfindelsen er kondensatoren Cl i ekstrakoblingen Z shuntet ved hjælp af en modstand R2, som i forhold til modstanden RI af RC-ledet har en større værdi. Dermed opnås den fordel, at der ved indtrædelsen af tegn med stoppolaritet over firtråd-strømkredsen F1 fjernes en eventuelt endnu forhåndenværende rest ladning på kondensatoren Cl. Man opnår dermed en veldefineret udgangsposition for en ny opladning af kondensatoren Cl og dermed en forvrængning fri overføring. For at sikre, at strømmen til sendeindretningen Al opretholdes under modtagelsen af skridt mod startpolaritet over firtråd-strømkredsen, hvilket er nødvendigt til undgåelse af utilladelige refleksioner, forefindes en i og for sig kendt holdemodstand Rh. I koblingen ifølge opfindelsen shunter denne modstand ikke blot kontakten bkl, som afbryder totråds-strømkredsen, men derudover også dioden D i ekstrakoblingen Z,According to the invention, the capacitor C1 in the auxiliary coupling Z is shunted by a resistor R2 which has a larger value relative to the resistor R1 of the RC-conductor. Thus, the advantage is obtained that upon the entry of stop polarity signs over the four-wire current circuit F1, any residual charge, if any, remains on the capacitor C1. Thus, a well-defined starting position is obtained for a new charge of the capacitor C1 and thus a distortion-free transmission. In order to ensure that the current to the transmitter A1 is maintained during the reception of steps toward the starting polarity across the four-wire circuit, which is necessary for the avoidance of inadmissible reflections, a holding resistance Rh is known per se. In the coupling according to the invention, this resistor not only shunts the contact bkl, which cuts off the two-wire circuit, but also the diode D in the auxiliary coupling Z,

Dette har den fordel, at dioden D foruden den nævnte funktion også sikrer en afkob-This has the advantage that, in addition to said function, the diode D also ensures a decoupling.

Claims

6 144109 the holding circuit for transmitting device AI from the subscriber connection circuit. This is necessary to prevent the current passing through the receiver magnet from switching off the transmitter AI, the voltage source TB and the holding resistor Rh. The connection coupling according to the invention, which without significant supply combines the advantages of the interconnection principle and the short-circuit keying principle, can be used with particular advantage when the line current, as recently proposed, is no longer adjusted over a line-completion resistor or its electronic balancing, for example. by means of an automatic control device by means of a control device located at the voltage source is set to a constant defined value, e.g. 40 mA. In the embodiment of FIG. 4, the last mentioned control device is denoted by K. The other design as well as the operation of the connection coupling AS correspond to the one already shown in FIG. 3 described. In the embodiment of FIG. 4, in which the line current setting is effected by means of a control coupling included in the coupling AS, the holding resistance, during which a starting polarity signal to the subscriber T1, maintains an enabling circuit for the transmitting device, in a further embodiment of the invention becomes zero. In this way, mandan obtains further advantage that only a single contact may be needed for disconnecting the two-wire single current circuit and for switching on the interconnection. An exemplary embodiment thus realized is shown in FIG. 5, in which the receiving device B, which acts as a key device in the four-wire circuit, has only one switching contact bk. Accordingly, in a coupling constructed according to this principle coupler means can be used, in which the division into two separate contact elements cannot or cannot be difficult only.

1. Converter coupling for transmitting DC telegraphic characters between a one-way and a two-way connection with a receiving and transmitting device, whereby the line current passing through a subscriber line (AnL) can be interrupted by the receiving device (B) in the rhythm of the arriving telegraph characters, which are to be is sent to the subscriber (TI) 'characterized in that there is an additional coupling (Z) between the two conductors of the subscriber line which, when disconnecting the line current passing through the subscriber line (AnL), is connected to the subscriber line by means of switching means (bkl, bk2) in the receiving device, that the auxiliary coupling (Z) contains a diode (D) and a RC-link (RI, Cl) connected in parallel with the diode and a capacitor (Cl) in the RC-joint coupled additional resistance (R2) and that the diode (D) in the auxiliary coupling in the case that the subscriber line (AnL) and a receiving magnetic device is capacitive (long subscriber line) are reconnected.