US2369868A - Telephone system - Google Patents

Description

Feb. 20, 1945. R TAYLOR ET AL 2,369,868

' TELEPHONE SYSTEM Filed April 15, 1940 10 Sheets-Sheet 1 Illllll DTU PCRS 9 mlunu m mentors REGINALD TAYL 0P GEORGE THOMAS BAKER Attorney Feb. 20, 1945.

R. TAYLOR ET AL TELEPHONE SYSTEM Filed April 15, 1940 l0 Sheets-Sheet 2 Mme/Mars REG/WALD TAYLOR 5g gee/vetmoms BAKER Attorney Feb. 20, 1945. R. TAYLOR ET AL. 2,369,868

7 TELEPHONE SYSTEM Filed April 15, 1940 10 Sheets-Sheet 5' lllHlllll //7 V6 174 ors REGINALD TAYLOR 5y GfORGE THOMAS BAKER Attomy Feb. 20, 1945.

R. TAYLOR ET AL TELEPHONE SYSTEM Filed April 15, 1940 PAS E I 10 Sheets-Sheet 4 llllllllll g 3 l|lllll|l|U- l lnvehtors REG/NA LD 7A YLOR GEORGE THOMS BAR Attorney -20, 1945 R. Wm ET AL 2,369,868

7 TELEPHONE SYSTEM Filed April 15, 1940 10 Sheets-Sheet 5 IZIS ICS

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v uunyjg l-IHHIIIIQ- a //7| en0rs REGINALD TAYLOR 6%565 THOMAS BAKE Aha/nay 1945- R. TAYLOR ET AL TELEPHONE SYSTEM Filed April 15, 1940 10 Sheets-Sheet 6 I/Zit D MRA IMP5 mus PS", J

/A 4/A -4.. a 551 I M as H" /n Mentors REGINALD TAYLOR 5 apes THOMAS BAK Feb. 20, 1945. R, TAYLOR ET AL 2,369,868

TELEFHONE SYSTEM Filed April 15, 1940 16 Sheets-Sheet v 5m? mvent'ors REG/NALD TAYLOR Z GEORGE THOMAS BAKER Feb. 20, 1945. 4 R TAYLOR ET AL 2,369,868

TELEPHONE SYSTEM Filed April 1 5, 1940 10 Sheets-Sheet s' E/[vl /U Wt IMPA Myento/s REG/MILD 7I4YLOR 5 GEORGE THOMAS BAKER Feb. '20, 1945. R. TAYLOR ET AL TELEPHONE SYSTEM Filed April 15, 1940 10 Sheets-Sheet 9 /n ventors REGINALD TA YLOR GEORGE THOMAS BAKER Afton? e51 Feb. 20, 1945. T YL R ET AL 2,369,868

TELEPHONE SYSTEM Filed April 15} 1940 10 Sheets-Sheet 1Q f/E. /Z

Patented Feb. 20, 1945 TELEPHONE SYSTEM Reginald Taylor and George Thomas Baker, piverpool, England, assignors, by mesne assignments, to Automatic Electric Laboratories, Inc.,'

Chicago, Ill.,'a corporation of Delaware Applicants April 15, 1940, Serial No. 329,608.

. I In Great Britain May 5, 1939 27 Claims. (c1. 179-71) The presentinvention. concerns improvements in or relating to arrangements for setting ,up' connections in telephone systems and is more particularly concerned with improved arrangements for dealing with;connections which re- ,quireto be recorded for charging purposes, that is to; say, connections which come outside the range in which the charge maybe determined by operating a meter individual to a calling subscriber one or more times and whereby such calls may be charged on the basis of duration as well as distance. a Generally speaking it is usual for connections local to an exchange area having a linked numbering scheme to be charged by operating the subscribers individual meter and in addition, thereby exchanges are also charged in this manner, although they are not in the area having the ,same linked numbering scheme as the area in which the call originates.

The characteristic feature, of the present invention is that call recording is adapted to, take place at the'sameexchange in an area as that at which the route to the destination exchange is determined, so that the number of the subscriber. wanted inthe linked numbering scheme with which the destination exchange is associated is transmitted iniull from the originating area direct to ,the' destination area aiter the call has 'beenset up to an exchange in the destination area, while the recording takes place at the exchange in the originating area from which such number is transmitted. 4

This invention may be applied in a variety of circumstances, for instancaexchanges at present in existence may be broadly classified into two different types, in one of which the linked numbering scheme is upon a decimal basis, and each subscribers number in the area covered by the linked numbering scheme has a given number of digits, for instance, 4, 5 or 6, each of which digits is represented by the setting of switches for establishing a connection having a direct numerical relation thereto. A second type of area is one in whichthelinked numbering scheme is based upon the initial digits representing an exchange name, and other digits representing the number of the subscriber. attached to that ex change; Frequently, sucfh exchange designating digits are represented by letters, and are caused by means of a register-translator to be translated into routing digits 'for transferring the call from the originating to the destination exchange the setting of the switches for such routing having no numerical relation to the numerical values-which may be assigned to such exchange-designating digits. On the other hand the numerical digits correspond to the setting of the switches in the destination exchange required to establish connection to a subscriber.

In this specification the first class of linked numbering scheme will be referred to as a nonregister-translator network and the second form of linked numbering schemewill be referred to 'as'a register-translator network.

The invention has application to setting up calls between .one non-register-translator network and ,another non-register-translator network, between a register-translator network and a non-register-translator network, between a non-register-translator network and a registertranslator network, between a register-translator network and another register-translator network and between a register-translator network and exchanges in the near vicinity of such network which may be of such a .distance as to necessitate the desirability of call recording facilities but otherwise are such that they could be included in the register-translator network.

It will be appreciated that generally speaking the register translator networks are of'very much greater extent than the non-register-translator networks.

At present in non-register-translator networks requ'ring say 5 or 6 digit numbers, metering is usually performed on a unit'fee basis, that is to say for local calls a single operation of a calling apparatus meter is effected while long distance calls are routed via amanual operator, for instance, by dialing 0.

In other cases a number of adjacent nonregister-translator networks are combined into a composite network of reasonable size. Intercommunication between various networks is made by dialling the required wanted number on th called network together with one or more prefix digits indicating such network. As each non-register-translator network will usually have its own linked numbering scheme, and with a view to keeping the number of digits down to a minimum, say nomore than 7 when calling from one register-translator network to another in the composite network, a simplified form of registertranslator or route-discriminator is associated with the outgoing junctions of each network so as to route the call to the desired network.

Such networks may be arranged to operate on a multi-fee basis.jThe number of times a sub: scribers meter is operated in response to the setting up or a callis determined by the routediscriminator in accordance with the particular number dialled. For calls outside the composite areas access to a manual number will usually be obtained by dialling 0.

Thirdly, in the case Ofcongested multi-exchange networks, register-translators will be used on all calls Within the network, irrespective of Whether the calling party is on the originating exchange or not, and in this case multi-fee metering facilities can readily be incorporated. The number of times a subscribers meter is operated for a given cause may for instance be determined in accordance with the particular level to. which the first or second code selector switch is set by the register-translator. For calls outside such areas the code letters TOL or TRU may be dialled and the calling party will be routed to a manual board at a toll or trunk exchange respectively. Alternatively, access can be had to an operator by simply dia1ling"0.

One of the applications of the invention is to the extension. of such networks, in view of the use of call recording or automatic ticketing apparatus, tov a size whereby subscriber dialling may become a feasible proposition over distances hitherto. requiring the charging. of a fee by an operator, based both upon the distance between subscribers and on the duration of the call. In this connection it may be mentioned that charging on a duration basis may be efiected by repeat multifee metering, but generally speaking it is usually considered preferable to limit. the. multiple fee to a value of the order of four unit fees or even less, as larger charges which cannot bechecked should preferably not be made on a subscribers individual meter.

Another application of the invention isto the construction of a national telephone exchange network which will permit calls being automatically set up by any subscriber toany other subscriber, regard being had to the desirability of reducing interference to existing networks and trunk and toll line layouts to a minimum, while at the same time keeping the additional equipment to a minimum.

While the invention has particular application to known telephone systems of the type'described above, it is not limited thereto, but it is adapted to be-used in addition in new-telephone-systems.

According to a subordinate feature of the in"- vention, calls set up from non-register-translator networks including main and satellite exchanges toother exchanges or networks for which call recording is required, are routed under subscrib; ers control to a main or central "exchange or the calling network where route-determining means are provided, for routing the call to the desired distant exchange or network, automatic recording of the call being effected at the same main or central exchange. I

While the characteristic feature of the invention as described above relates to the provision of route-determining and call recording means at the same central exchange of a network there may be circumstances in which all calls from a non-register-translator network .fo'r'whi'ch call recording service is required may pass through a nearby register translator network and according to a further feature of the invention a single group of junction lines is provided between the central exchange (which may be a main exchange) of a non-register-translatbr network to a central or sub-central exchange of a registertranslator network and "as an idle one of such.

junction lines would be automatically selected under subscriber control there is no necessity for providing any route-determining means at the central exchange of the non-register-translator network, and further according to this feature of the invention route-determining means would be provided at the central or sub-central exchange of the register-translator network while the call recording equipment would be provided at the central exchange of the ncn-register-translator network, the distinguishing digits of the wanted exchange being transmitted under subscriber control to the route-determining means at the central or sub-central exchange of the register-translator network.

According to a further feature of the invention in a telephone arrangement or like system comprising a register-translator network having access to a plurality of other networks which may be register-translator networks or non-registertranslator networks or both, the register-translator is adapted to be taken into use at the origination of an inter-network call to route the call to a central or sub-central exchange of the register-translator network and a second registertranslator is adapted to be taken into use at said central or sub-central exchange to route the call to the desired network, call recording equipment being also adapted to be taken into use at said central or sub-central exchange for recording the 'call.

According to a further feature of the invention and particularly applicable in register-translator networks, a register-translator is provided which is adapted either to route a call to an operators position or to route a call to a call recording position for inter-network calls according to the value of the digit received after the registertranslator has been taken into use.

By this feature of the invention it is possible to utilise the existing arrangement whereby for calls to an operator the subscriber dials the digit 0, in this case a call would be routed to an opera'to'r either by dialling digit 00 or by dialling the digit 0 and delaying to dial any subsequent digit, while if a subsequent digit has followed the first digit other-than digit "0 then the call would be route'd'to'acall recording position.

According to a further feature of the invention a regi-s'ter-translator network may be extended by adding exchanges or exchange networks which would involve the possibility of calls being made between subscribers in the extended network which should be charged for by call'rec'ording and according to a further feature of the invention a register-translator is adapted to be taken into use at the exchange at which or at a satellite of which thecall originated while a second registertranslator is adapted to be taken into use at a central or sub-central exchange by which access is had to the wanted exchange, recording equipment being also adapted to be taken into use at a central or sub-central exchange to enable the call to be recorded.

A further feature of the invention .is concerned with special arrangements to enable calls to be setup for a very large area or nationally according to which feature the network. covering the whole area is dividedlinto a number of zones-each having one or morezone central exchanges and eac'hzone being. divided into. groups while the groups ,in .turn each have one or moregroup-centralexchanges and eachgroup is sub-divided into a'number of exchanges or exchange networks.

aseascs each of;suchxexchanges or networks havlng'its ownlinked numbering scheme. In such a net-i workaccording ,tothis feature of the invention r nte-dete rmining means by which the routetro 'ng digits by which a call is to be set up from the calling groupor zone to the called group or zone are determined, together with means for.

recording particulars of the call are located at a group centralexchange or a zone central exchange in thecalling group or zone.

I The following arrangements correspond to subsidiary'featuresof the invention which while they fare .protected in co-pending applications have particularapplication in carrying out-the features of the invention.

Incall recording number of the calling line and according to one subsidiary. feature of the invention the identity'of thjcalling'line is ascertained and. stored at' the calling exchange on the initiationof the call over. the" junction line and subsequently. the stored identity. together with that, of the callingex-- changeis transmitted to the recordingexchange on the termination of theconnection, 1 According to another subsidiary feature of the invention mechanical impulse generators are providedffor storing digits dialled by a subscriber i-t'isnecessary to identify the. In

interienetwork calls a simplified form of register-..

translater equipment, which will be known by the term route discriminating equipment, isutilised,

and in which on-suchw calls feecharging which is access to a main exchange manual board is had by dialling the digits 00.

Fig. 4 shows the layout of a register translator network with a number of tandem or sub-central until the appropriate equipment is in a position to receive the same.

' Accordingto a further subsidiary feature of the invention the information to be recorded is stored until the end of the connection and is then transferred'to a recording or printer controlling unit atwhi'chother information is added and the whole of the information to be recorded or printed is duly transferred in rapid manner to the printer and recorder so that only a few printers and recorders need be provided for a large number of recording positions. I

lAnother feature'of the invention which is particularlyfadvantageous for use in transferring a number rapidly over the connection 'in code and exchanges'tl'ierein at which will be located call recording equipment required in connection with certain types of calls either completed within the area or to exchanges or networks outside the area.

Fig. 5 shows a trunking-diagram for the routing and. recording of a typical call from an exchange within a register translator area to an outlying exchange or networkvia a sub-central exchange. Fig. 6 shows the trunking arrangements involved in local and sub-centralregister-translator exchanges when different classes of traffic requiring calling subscriber identification are combined in a commongroup at a central exchange or point. Fig. Yfis concerned with trunking arrangementsior the purpose of automatically setting up and recording calls on a national basis and shows typical trunking arrangements involved in ad'istribution of incoming calls at a zone centre storing it in a cheap manner until it is required,

concerns'animpulse regenerator which is adapted to'respond to two sets ofv pulses, the pulses of one iSBt having a definite timed relationship with respect to the pulses of the other set andin which the two sets of pulses are adapted to be re-transmitted in substantially the same form as received." Conveniently the impulse regeneratoris constructed as described in McClew and y -Wo0dlands UnitedStates Patent No. 2,188,461,

issued January 30, 1941, and according to the invention a member is movedby a receiving magnet to an extent determined by one set of pulses while pins are displaced during such movement in responseto' a'second set of pulses acting upon a marking magnet, such second set of pulses having a definite timed relationship with respect to the first set, an impulse' generator controlled thereby is adapted when released to operate and generate pulses corresponding in number to said first set of pulses and to the extent of movement of said member while a further impulse generator is provided adapted to be operated as each displaced pin isencountered to generate pulses corresponding to the second set of pulses.

These and other features of the invention will be better understood from a description of the following embodiments thereof which are given by way of example, reference being had tothe accompanying drawings.

Fig. l'shows the layout outof a number of such networks in which for.

V of two non-register translator telephone networks which may be two exchange and also at a group exchange in the and 12 when arranged side by side show the circuits of a toll line relay set. These pieces of apparatus'f are particularly. adapted for use in register translator areas of the type shown in Figs. 4 and 5, but it willv be appreciated that the circuits of equivalent apparatus in other areas may be designed on a similar basis.

For the purpose of identifying a calling point, identification and storage equipment of the type disclosed in our Patent No. 525,902, issued November 28, 1940, may be utilised, while equipment and circuits on the general lines described in Ostlines application No. 278,729, filed June 12, 1939, may also be brought into use for the pur pose of carrying out the invention. 7

Reference should now be had to Fig. 1 andit will be understood that intercommunication between the two networks shown and also between either ofv these networks and other networks which are notshown would hitherto be effected via the manual boards of the main exchanges B and C through which internetwork calls are set up, and arrangementswill be described whereby such'calls may be set up and recorded automatically. i

i For the purpose of simplicity each networkis merely, assumed to comprise a main exchange such as B or C and a number of satellite exchanges suchas A and D and the setting up of calls by'subscribers on exchanges A'and B will now be considered, reference being had to the trunking diagram of Fig. 2.

It will be understood that each network will have its own linked numbering scheme, and a two or three digit code will be prefixed to the wanted subscriber's number in the case of inter-network calls. For the purpose of discrimination between local linked number and inter-network calls, all calls of the latter class will be prefixedby a cornmon previously unused first digit, such as 8, followed by one or more prefix digits together with the called number in the required network. The dialling of a first digit 8 by subscribers having unrestricted access facilities will cause the connection to be routed at the main exchange to a toll line relay set which can take into use translating and call recording equipment, the translating or so-called route discriminating equipment bringing about routing 'of the call to the required network either directly or via intermediate networks.

Considering the case of a call originated by a subscriber on the satellite exchange A, it will be seen that two groups of junctions are assumed to be provided from this exchange to its parent exchange B, these being divided up into ordinary and high grade junctions.

When the subscriber removes his receiver he is connected via the line finder LE to a discriminating selector repeater DSR associated therewith, and this switch thereupon-associates itself with an incoming selector ISR at the main exchange via the hunting switch U/S and the ordinary junction line 10 in Well-known manner.

If the first digit dialled is any of the numbers 1-7 and 9 which indicate that a subscriber in the local linked numbering scheme is required either'of satellite exchange A, of the main exchange B or of any of the other exchanges in the calling network, selector repeater DSR after having been stepped in parallel with the incoming selector ISR in accordance with the digit dialled will either release the junction in the case of a local or adjacent exchange call and connect up with a local second selector, or will retain the junction connection and will repeat subsequent digits dialled over the junction l0, incoming selector ISR and outlets such as [2 to switches connecting with the required subscriber either on the main exchange B or on other exchanges in the calling network directly connected to this exchange.

In case the first digit dialled is "0 the ordinary junction ill is released and the call is routed over the high grade junction II to the main exchange manual board, a suitable discriminating signal being sent from the satelllte'exchange out going relay set ORS to the main exchange discriminating relay set DRS so as to cause the connection to be routed to the main exchange manual board jack 0. In case a coin box subscriber should be calling, a difierent signal will be extended to the relay set DRS so as to cause the connection to be routed to a coin box jack CB at the main exchange manual board.

If the calling party wishes to set up an internetwork call, the first digit. dialled will be 8 in which case the ordinary junction I0 is released as before and the high grade junction I I is taken into use from the DSR level 8, a distinctive signal being transmitted from the outgoing relay set ORS to switch the connection at the rel'ayset DRS to the toll line relay set TLBS. Coin box subscribers dialling this digit andnot being enill titled to originate such calls on an automatic basis are barred access thereto either by the extension -of a suitable signal from the relay set ORS which causes the relay set DRS to transfer the connection to the coin box (CB) jacks on the main exchange manual board or due to the factv that there will be no access to the relay set ORS from level 8 of the special group of DSR switches provided for suchsubscribers.

When the relay set TLRS isseized, access is had to an outgoing selector OGS, while the hunter switch HS is caused to associate itself with an idle route discriminator RD. Before the question of call recording is considered, the routing of the call to its required destination will be described, and in this connection one or more digits subsequent to the first dialled digit are received on the route discriminator effects the necessary translation and transmits the required routing digits out via the toll line relay set, the outgoing switch and subsequent switches to gain access to the incoming switch at the main exchange of the desired network. Ihe toll line relay set will be provided with an impulse storage and regenerating device for instance of the electro-mechanical type disclosed in McClew and Woodlands United States Patent No. 2,188,461, and this will serve to store the remainder of the digits dialled during the transmission of the translated digits from the route discriminator.

When the routing digits have all been sent out, the impulse storage and regenerating device in the relay set TLRS is caused to send out the digits stored therein in untranslated form, so as to complete the connection to the wanted party.

Considering the question of recording such calls, the minimum amount of information required to enable the'call to be charged against the calling subscriber will consist of the calling number and the called number, and if the call is to be charged on a time basis, the duration of the call, together possibly with the time and date.

For the purpose of calling number identification it will be understood that as a result of the setting up of an inter-network call, the outgoing relay set ORS at exchange A will be caused, either during the setting. up of the connection, or on reply of the called party, or during or at the end of conversation, according to which proves the most convenient, to associate itself over finder switch RSF' with a storage control relay set SC which in turn connects with an identification control relay set IC. This on being seized sets into operation an identification switch SS which operates in the manner described in British Patent 525,902, whereupon the identity of the calling line will be determined and stored in the outgoing relay set ORS, storing being effected as described for instance in British Patent 525,902.

In connection with the storing of the calling number at the originating exchange until it is required at the exchange where call recording equipment is provided, if this is effected by means of storage relays and a uni-directional sending switch as described'in British Patent 525,902, then it will not be necessary to provide the relay set SC and the finder switch RSF since the calling number can be communicated direct to the relay set ORS. Use might however be made of an electromechanical storage andv regenerating device in the relay set CR8, and in this instance it may prove preferable to utilize a common storage con trol set SC and finder switch R'SF as shown in which in response thereto Fig. 2 in order that the signals characterising the identity ofthe calling party may be firstly re- I ceived on either relays or a stepping switch in the common relay set SC. The relays'or stepping switch convert the signals received into markings suitable for setting the 'regenerator in the-relayv 7 set-ORS in such a manner that the number can be subsequently retransmitted therefrom in code to the distant exchange.

As regards the called number, the digits dialled into the toll line relay set 'ILRS are stored for instance on relays and at termination of conversation the hunter switch HS, which it will be notedhas its bank split so as to gain access successively to' the route discriminator and to call recording equipment as required, is caused to associate itself with a printing or recording controller PCRS whereupon .the calling partys numberwillbe transmitted thereto from the outgoing relay s'et'at exchange A and the junction'll will be released after-which the called partys number recorder controlling apparatus the tariiT being determined at the end of conversation. I The general arrangement of the printer. or recorder controlling apparatus may conveniently followvthe .designof the printer controller as de scribed in Ostlines application No. 278,729 filed June 12., 1939, suitably modified to meet the con-v ditions described above while the printer or recorder'itself will be such as to be only taken into use when the information is ready for immediate printing and recording.

Theroute discriminator described diners from the normal register-translators such as are used in multi-exchange areasin that it is only required to receive initial digitsof a dialled number and'in satellite exchanges could of course be replaced by ordinary first selector switches which on seizure would gain access to common discrimination equipment over a hunter switch, this discrimination equipment serving to determine whether the call was to be metered or to'be charged for by means of automatic call recording equipment and causing the-connection to be routed at the main exchange accordingly. The discrimination equipment may generally follow the lines of that disclosed in Taylor and Bakers Patent No. 2,232,189, issued February 18, 1941.

The invention is not limited to the simple example shown, as obviously each network havin its own linked numbering scheme could have associated therewitha number of dependent networks, each having its own numbering scheme. If it wasconsidered desirable to ticket calls from an exchange in a linked numbering scheme to a dependent network thereon this could be readily effected in the manner already described and such calls would then have a common prefix digit such as 8.

As a further extension of the scheme, a number of multi-fee areas each comprisin a plurality of exchange networks operating ona multipl fee basis for inter-network calls couldbe linked up automatically on a call recording basis. In such a case recorded inter-area calls will be routed via the centralexchange of each areaat which the call recording equipment will be located and it may be that in some circumstances calls between exchanges in adjacent areas but which are only a unit fee distance apart will be completed on a, call recording basis. Coin box subscribers setting up such unit fee. connections would however be routed to a manual board.

In case no spare first digit is available for use on inter-network calls it might be arranged that for main. exchange manual board calls the digits 1 00 would be dialed,'while for calls requiring re response thereto to route the call to the required exchange or network whereas the register-translator is adapted to receive a full dialled number and inresponse thereto to route the call right throughto the required party. If therefore the route-discriminator is adapted toperform the full functions of a register-translator then the impulse storage andregenerator device in the toll linerelay set can servefor the purpose of storing the called number until this information is required for toll recording purposes, and it will not be necessary to provide storage relays in the toll line relay. set for this purpose.

. As regardscalls originated by main exchange subscribers, such subscribers gain access to the first numerical selector SR. over a lead such as l3 and the setting. up of calls which require recording follows-along the lines already described.

- Although in the arrangement described manual boardand inter-network callsare routed over one group of junctions, and ordinary linkednumber calls over another group'of'junctions, a single group of junctions to the main exchange may be provided to serve all classes of traffic, discriminating signals being utilisedto. efiect the correct routing of-the call at the main exchange.

.The discriminating, selector switches at the dialled.

cording digits 01-09 would be dialled.

Fig. 3 shows typical trunking arrangements at a satellite exchange A and main exchange B in which levelO is utilised to gain access to dialled toll exchanges. It will be seen that the equipment at exchange A follows on the lines of that already described in connection with Fig. 2, a discriminating selector repeater being provided in this exchange and having access to a high grade junction l l via an outgoing relay set ORS.

If the first digit dialled is 0, access will behad to a discriminating relay set DRS at exchange B and in the case of an ordinar subscriber calling, if he fails to dial a further digit within'a predetermined period the connection will be routed to the main exchange manual board. If

a coin box subscriber having restricted access is calling, the connection will be immediately routed to the main exchange manual board. When the relay set DRS is seized it associates itself with a free toll line relay set TLRS over a hunter switch and this relay set receives the second digit If this digit is 0 thereby indicating that a-manual board call is required, a signal will be i sent back from the relay set TLRS to the relay set DRS so as to transfer the connection to the manual board, but if the second digit is 1-9 then the toll line relay set will direct this digit to a route discriminator. in the manner already described in connection with Fig. 2. Call recording is subsequently performed in the manner already described.

In the case of calls originated by main exchange subscribers, if 0 is dialled as a first digit access will be had from the selector S to a stor--' age and discriminating relay set SDRS which functions in the same way as the relay set DRS except that in addition it has provision for storing the identity of the calling party until this is required for call recording purposes.

Outgoing toll calls from the manual board are handled via the jack O/G which has access to the required by the route discriminator, the storage and regenerative device might be arranged only to re-transmit immediately. those dialled digits which are required by the route discriminator. The remainder of the digits dialled will then be held until all the routing digits have been sent out from the route discriminator after which they may be retransmitted to complete the setting up of the connection. 1

In case the DSR at the satellite exchange is replaced by an ordinary selector switch having access to a common discriminating unit as pre- Viously mentioned, the storage and regenerative device in this unit could be arranged to have a controlled sending-out facility thereby avoiding the use of an intermediate storage and regenerative device.

Areas to which the invention may be applied may include networks having dependent networks and/or exchanges thereon and it is often usual in the case of calls from dependent exchanges to dial one or more prefix digits in order to gain access to the parent exchange. In such a case if a call requiring call recording facilities is required, the number of digits to be dialled would include the initial prefix digits to gain access to themain exchange, the digit or digits required to Y route the connection via the intermediary of the route discriminator, together with the called number on the wanted network. In order therefore that the number of digits to be dialled might be reduced, equipment might be provided at the various dependent exchanges which, in response to the dialling of a digit or digits indicating a call requiring call recording facilities, would elTect a predetermined translation to route the call to common route discriminating and/or call recording apparatus at the main exchange, after which some or all of the initial digits would be transmitted thereto together with the remainder of the digits dialled in untranslated form.

The arrangement described with relation to Fig. 3 assumes that the trunk line relay set TLR-S has access both to route-determining arrangements as well as to call-recording apparatus in the same way as in Fig. 2, but in the case of calls to or through a register-translator network which may in fact be the only calls for which call recording facilities are to be provided, a single group of directjunctions is provided from a main exchange, such as B, to a central or the subcentral exchange most conveniently situated forreceiving calls from the non-register-translator network. In such as case there is no necessity for providing special route determiningmeans, at the central exchange of the non-register-translater network, the route being already deter- 'of the wanted party may be translated.

Considering new methods by which the scope of multi-ofiice areas of the register-translator type can be extended so as to include outlying networks or exchanges, and by which calls therebetween can be charged either on a call record ing or a multi-fee metering basis in accordance with the particular conditions obtaining there are two preferable methods which can be utilised in the case of extension to existing networks.

According to one method the unusable codes in a register-translator area numbering scheme are used for the purpose of handling calls to outlying districts thereof. It is appreciated that most of these codes cannot be arranged to represent thefirst letters of an exchange name but they can instead be used either as numerical prefixes or alternatively on a mixed letter and numerical basis if this should prove to be preferable from the subscribers point of view.

In another method advantage is taken of the fact that at present the dialling of digit 0 in a register-translator area causes the seizure of a register-translator adapted to be seized also when some other digit or digits are dialled, different kinds of access being provided so that said register translator will route the call either to an operators osition in response to the dialling of digit 0 or to another subscriber in response to other digits. It is proposed that a special set of 0 level simplified register-translators shall be provided, it being arranged that all calls requiring the use of call recording equipment are preceded by the digit "0 followed by other extra digits as required, and the full number of the called party in the wanted exchange.

If the first digit dialled is "0 and is not followed by another digit within a short interval of time, say three seconds, the call will be routed to a manual board via which a long distance call may be completed if desired, while the call will also be routed to this manual board if the digits "00 are dialed, the dialling of these two digits being the new method of calling an operator.

If digits 01 to 09 are dialled as the first two digits access to routes requiring call recording facilities will be provided. If the 0 only is dialled as a first digit by a coin box subscriber he is either immediately routed to a manual bord or given NU tone from one of the first code selectors which would be takeninto use by such subscribers.

Each exchange will thus be provided with a single group of 0 level register-translators which give access to means forrouting long distance traffic whether this is handled either on a full automatic basis or via a manual board. These register-translators are in turn arranged to give access to call recording and/ or register-translator apparatus grouped at a central exchange in the area.

A description will first be given of the first scheme by reference to the register-translator layout of Fig. 4. Four of the exchanges shown shaded A-D within the existing area as defined by the dotted line are assumed to serve as subexchange 'F and in which the is on :exchangeE, it will be assumed by way of central exchanges. Callsto outlying networks or exchanges suchas E will be routed via one or more sub-central exchanges,-at which call recording equipment will be provided in addition to registertranslator equipment.

It will be understood that certain of the exchanges within the normal register translator- "area but near the fringe thereof may be operated cation being initiated and stored at the calling exchange at any convenient stage during the call.

It may be that calls to the outlying exchange E can be set up on a single or multi-metering basis owing to the close'proximity of the calling and called exchanges, and in such a case calls to exchange E will be operated on an ordinary single on 'a single or multi-mete'ring basis to exchanges outside'the area, while calls from other exchanges within the area to the same outlying exchange will be operated on the call recording basis. Againit call recording for cerfor instance when such maybe. desirable to utilise tain calls within the area,

"calls extend from one end of the-area to the other.

' Considering now the case of a call originated at example that the required subscribers number is 746.9762, the "digits 746 being a suitable previously unused code in the register-translator area.

Reference should .now'be had to the trunking diagram of Fig.95. A calling party on removing his receiver will be connected via his uni-selector U/Sto a first code selector ICS at the local exchange which thereupon in known manner associates itself with an idle A digit switch LADS over the hunter switch LADI-I. In response to the dialling of the first digit 'lone of the level 7 group of local register-translators LRT will be taken in useand will receive the remainder of the digits dialled. The second and third digits dialled;

required subscriber or multi-meteling basis when originated by subscribers at exchange B and possibly in the near vicinity thereof, while calls to exchange E from other exchanges in the register-translator area will be operated on a call recording basis. Under these conditions the same group of register translators at the all classes of call since the existing register-translators will alreadyhave been arranged to cater for routing out to the outying exchange involved.

. In the case of calls from say exchange H to exchange E,it is feasible that the six translations normally available in the existing register-translater at exchange H will be suflicient to allow .for the provision of routing out to the required exchange Eand also for repeating the dialled three. digit code to the tandem exchange B. In this case therefore there will be no necessity to take into use a register-translator at the tandem exchange, and the toll line relay set thereat if call recording "is require-d will simply store the called .number until the end of the conversation.

namely 46, are thereupon translated to, say985.

soas to route the call via exchanges such as-D and G to the sub-central or tandem exchange .13

having access to the outlying exchange E. The

routin digits are then followed by the complete number dialled, namely 746.9762, which will be required at said exchange B both for the purpose of enabling the call to be routed out to the desired network or exchange, and also for the purpose of call recording. The transmission of the routing digits 985 will gain access via the sub-central incoming selector 'IISR to a switch THS, the banks of which are split so as to gain access successively to A digit switches andcall recording equipment asrequired'.

During the hunting or the switch TI-IS a signal will be sent back to hold uptheregister-trans lator at the local exchange and when anidle switch TADS has beenfound, the local registertranslator LRT will commence to send outfthe complete number dialled. v, p

The register-translators such as TRT taken into use at the tandem exchange may be in a special group arranged to provide translations for routing calls to outlying exchanges and/or net- 2 works served by the tandem exchange, which net works may include one or more registentrans lator networks. As before, digit 7 will be received on the A digit switch and subsequent ldigits will be on the level 7 group of register-translators toll line relay set such as TLRS, and this thereupon associates itself with an idle A digit switch TADS over the hunter gain access with the called party It isuappreciated that where existing register it will not be possible translators .are made use of to cater for more than four numerical digits in addition to the code letters and/or digits, and

in some circumstances it may prove desirable to modify the existing equipment so as to provide for the storing of five or more numerical digits;

Consideration will now be given to the second proposed method by J which a special group of register-translators is provided in an originating exchange for handling. calls requiring call recordingfacilities whether recording be effected manually by an operator or automatically.

,Sincethe number of routings to be made by these translators will be small compared with the numberof'translations'to be made by translators serving other A.- digit switch levels, they may be of simpler construction. As described in connection with the first method it is necessary when setting up a'recorded connection to route the call through'from the calling exchange to a sub-centralexchange which handles traffic to the call' recording required exchange after which the complete number dialled is repeated thereto and for the purpose of storing and re-transmitting the wanted numberthe special group of 0* level register translators maybe provided with electromechanical" impulse storage and regenerative mechanisms, of the type already mentioned.

- As a preferred alternative it may be arrang d that when for instance a call is originated at exchange F in Fig. 4 and is destined for exchange 1 E, the "0 level register-translator at xchange F will not, as describedalready, route the call directly to-the tandem exchange B nearest to the outlying exchange E. in response tothe dialling of a toll code'numbercommencing with digits 01-09, but will; simply route the call to the parent tandem exchange D of the calling'exchange F and at this exchange D there will be located the equipment for exchanges such as e The advantage of this scheme is that the 0 level translators at each group of exchanges op eratinginto a parent tandem'exchange will only haveito have provision-for effecting two routings,

tandem exchange B will be used for one to a manual board .at the parent tandem exchange and another to a relay set thereat which has access firstly to a register-translator or route-discriminator which efiects routing of the call to the required outlying exchange and secondly to call recording equipment. This method enables the equipment in the level register-translators to be reducedto a minimum;

Such an 0 level register-translator is described later with reference to Figs. 8 and 9.

In connection wtih the handling of call recorded trafiic it is further proposed according to the invention that all types of traflic requiring identification of the calling party should be combined in a common group to a central point, and in order that certain types of subscribers, for instance coin box subscribers, may have restricted access facilities, access will be had to this common group from two different switch levels one Of which is barred on those selectors serving the special subscribers having restricted access. Means will be provided at said central point to separate the various types of trafiic.

Referring now to Fig. 6 it will be seen that two groups of first code selectors ICS (CB) and 108 are provided at the calling exchange for coin box and regular subscribers respectively, each having access to the same group of local register translators LRT, the other equipment involved being the same as that described in connection with Fig. 5. Both the regular and coin box first code selectors have access over level such as 8 to the outgoing junctions to the main xchange, and this level would be used in the case where either type of subscriber required access to a manual board at the subcentral exchange. In accordance with the particular routing digit received on the incoming selector 'I'ISR at the sub central exchange, access will be had either to an ordinary manual position via the jack designated 00 or to trunk, toll'or telegram. positions via the jacks labelled TRU, TOL and TEL. Other types of connections which require to be set up via a manual position may be given access via other levels of selector TISR to different jacks. Suitable discrimination will be given to these positions as to which type of subscriber is calling whether ordinary or coin box, the discriminatory signals being transmitted from the outgoing relay set ORS in accordance with the particular type of first code selector from which it has been seized. In the case of. a call originated by an ordinary subscriber, it could either be arranged that immediately the operator plugged in to the jack subscriber identification equipment will be started up from the outgoing relay set ORS at the local exchange, after which the calling number will be transmitted to the central point or alternatively the actual starting. up of the identification equipment could be under control of the operator. This latter arrangement would be generally employed from the 00 operators position since such an operator may in some cases be merely assisting subscribers, while in other cases she may complete a call therefor possibly to some exchange which requires'call recording facilities when she will require to know the identity of the calling party. In all these cases the calling number will be preferably displayed on some form of indicator in front of the operator, the actual period of display being under her control.

It will be noted that level I of the incoming selector TISR is arranged to connect via a toll relay set 'ILRS to outgoing selectors SRI and discriminators will also SR2 and it will be arranged that where a calling party desires such a connection, the first code selector at the local exchange will be raised to a level such as '7, so that if the calling party is a regular subscriber the connection can be completed in the manner described in connection with Fig. 5, While if the calling party is a coin box subscriber, the connection will not be completed because the coin-box first code selector 103 (GB) does not have access to the outgoing junctions over level 7. A "number unobtainable tone in such a case will be given to the calling party and the register-translator taken into use will be released.

In regard to incoming calls from outlying ex ohanges to a. multi-ofilce register-translator network, direct junctions will be provided from the calling exchange or the main exchange of the calling network to one of the central or subcentral exchanges in the register-translator net Work. The incoming junctions will preferably be terminated on a new rank of first code selectors and these will have access to the ordinary register-translators provided in the sub-central exchange, and the routing of calls to exchanges within the register translator area will proceed in the ordinary well-known manner. As regards the charging of such calls, discriminating equipment will be provided at the originating exchange to determine whether charging shall be on an ordinary metering or call recording basis. These be provided with impulse storage and regenerative devices so as to enable some or all of the digits dialled therein to be repeated to the sub-central exchange for the purpose of setting up the call via the sub-central register-translators. In case a call requires recording, the discriminator at the originating exchange will be arranged to'transmit a signal to the sub-central exchange so as to cause call recording equipment to be taken into use. The recording equipment will store particulars of the wanted partys number during conversation, while the identity of the calling party will be determined and stored at an outgoing relay set in the originating exchange. At the end of conversation a printing or recording controller will be taken into use and the particulars required for charging purposes will be communicated thereto in the manner already described.

In the typical trunkin diagrams of Figs. 1-6 which have now been described, the circuits of most of the items ofapparatus involved therein are known to those versed in the automatic telephone switching art, while in some cases relevant patent specifications have been cited.

Consideration will, however, :be given to the circuit operations involved in setting up calls via the intermediary of a simplified 0 level register-translator located at an exchange such as F in the register-translator area of Fig. 4, it being assumed that such register-translators are adapted in response to the dialling of digit 0, or digits 00 to route the call to a manual board at the parent tandem exchange D, and in response to the dialling ofjany of the pairs of digits 01-09 to route the call to exchange D, after which the complete number dialled, with the exception of the first digit 0 which is of no further use in the setting up of the call, is repeated in unchanged form thereto.

Atoll line relay set is taken into use at exchange D and gains access firstly either to a register-translator which has facilities for routing the call to any of the outlying exchanges is earthedat the first code either directly or via-the intermediary of other exchanges in the area.

tandem exchange manual board ortoll line relay set in accordance with the particular second digit dialled.

For the purpose of routing and call recording it is also necessary to have details of the full called number at the tandemexchange and the storage and retransmissionof this information is effected by meansof a mechanical impulse and storing-regenerative device of the type already mentioned.

Considering the circuit operations, it will be understood-that the circuits of the first code selector and A digit selector 'may be of the type disclosed in our British Patent No. 469,184 which also disclosed a typical ordinary register-translate-r. When an A'digit selector switch seizes the 5 level register-translator of Figs. 8 and 9 in response to the dialling of the first digit 0,, its

wiper switching relay responds to battery mark-,

ving the idle condition of the register translator.

Such battery is connected to the P lead via the upper'winding of relay A in paralle1 with resistance YA andthereupon extends an earth forward to-operaterelay A, whereupon relay B is operated in series with themagnet RM (non-operative in this condition), and this relay in turn brings up relay BBQ Relay BB in operating at armature bb3 brings up relay P, at armature bb5 extendsealth on to the common motor start lead H to set in operation the S and Z pulse delay timing equipment associated with relay TP and M and to set in operation the motor which drives the impulsing springs IMPI and IMPZ required by the register-translator for sending out the translated dialled code. At armature'bbl an impulsing circuit'is prepared to a regenerator receiving magl net RM, at armature bb8 an impulsing circuit is prepared to the magnet FM of the reverse drive electro-magnetically operated switch F, while at armature 'bb9 the upper winding of relay A is disconnected from the incoming P lead but this relay remains held over the pulsing lead PU which selector impulsing relay armature. I

The dialled digitreceived at the register-translater will beany'of the digits 1-0 and this will be received on relay A Which' in responding thereto at armature a2 repeats the impulse train to the magnet FM and-steps the switch wipers roundto a position corresponding to the digit dialled. At the'same time at armature al the impulse trainis repeated to the regenerator receiving magnet RM, it being noted that resistance YB in series therewith is now short-circuited by armature bbl so as to enable the magnet to respond to the impulses; the resistance YB serves to prevent premature operation of'the magnet RM during the energisation of relay A. During the impulse train relay B is intermittently short-circuited by armature al but it remains operated due to the slugging effect of the short-circuiting, while relay C operates on the first release of relay A and subsequently holds thorughout the train, and at its armature cl energisesjthe regenerator marking magnet MM.

Considering briefly the'lmpulse storing and rereceives the second digit The toll line relay set also can gain access to call recording equipment I comprises essentially a generating device, it will be understood from details given in the prior specification that it receiving disc and, sending disc which are arranged on either side of a plate carrying a circular row of pins. The receiving disc is rotated step-by-step in response to the impulses received on the magnet RM and carries with it a marking lever which is released on deenergisation of the marking magnet MM at the end of. each train of impulses, and pushes a pin corresponding to the digit dialled through the pin plate into the path of the sending disc. For each digit received a corresponding pin is pushed through the plate and these pins serve to regulate the movement of the sending disc which controls .the generation of outgoing impulses by the re.- generator impulse springs IMP3.

1 Returning again to the storage of the first digit on the regenerator, when the magnet RM responds and commences to rotate the receiving disc step-by-step, the first movement of this disc brings about the mechanical operation of the regenerator off normal springs and a circuit is thereupon prepared for relay ON over contacts NI At the end of the impulse train relay A remains steadily operated and on release of relay C after its slow period governed by the short-circuiting of its winding, the circuit for themarking magnet MM is opened andthis magnet restores thereby causing the lever carried by the receiving disc to release and to push a pin corresponding to the digit dialled into the path of the sending disc. I

Atthe same time the contacts mm controlled by the marking magnet close after having been opened during the energisation of the magnet and in so doing complete a circuit for relay ON which thereupon operates and locks for the remainder of the setting operation over its armature on! and oid-normal contacts NI to earth.

While the magnet RMofthe regenerator is being operated over contact al, th'e'magnet FM of switch F is'operated over contact a2 so that the second digit is registered on both the regenerator and the switch F.

It will be remembered that in case the calling subscriber wishes to gain access to a manual board subscriber, the two digits 00 will be dialled in which case the second digit 0. will be stored on the regenerator, while the switch F will be set to position ll. Contact II on the F4 bank is cross connected to a terminal 12 so that on release of relay C at the end of the train earth is extended over wiper and'bank F4 to bring up relay SM, which in amanner to be later described initiates the routing of the call to the manual board. Contacts 2-l 0 on the F4 bank corresponding to a second digit 19 which are dialled when a toll call is being set up, are cross connected to a terminal I3 so that relay SC is operated in this case and at armature s02 completes a locking circuit for itself.

In response to the dialling of digits 1-9 as a second digit, the register translator is caused to send out'trains of pulses to effect the routing of the call to the parent tandem exchange and hence when relay SC operates a circuit is prepared to relay IG. 7

Connected in parallel with this relay are a pair of impulsing springs IMP2, which it will be understood are operated in conjunction with the outgoing'lo'op impulsing springs IMPI in such a manner that when springs IMPI are closed the IMP2 springs are open and vice versa.

The motor controlling-these impulse springs has previously been set into operation, and when impulsing springs IMPZ make their first break after theoperation ofrelay SC,.relay IG. isoperated. At armature igl. the impulsing. springs IMPE are connected up. tov the. magnet PM of switch F and at armature igZ a short-circuit-is removed from theimpulsing springs IMPI At armatures 2'93 andz'g4 the circuits to relaysSC and SM are disconnected fromthebank. F4. of switch F, and bank FB-is now connected upv at armature ig5 to relay SZ so that it may now be used for the purpose of controlling the total numberof trains of impulses to be sent. out from the register-translator. At armature igB theearth supply to wipers F4 and F8 is rendered independent of the armature 02 so that if further impulse trains are being received during the ensuing transmission, each resultant operation andrelease ofrelay C will be withoutefiect: on this part of the circuit.

The above-described. relationship between: the impulse springs'IMPl and IMPZ. is suchthat for each step the F switch is causedto take by. means of the impulse springs IMPZ an impulse willbe sent out over the left-hand negative and positive conductors via the impulse springs IMPL. Initially, however, the impulse springs IMP! are shortecircuited over a path including resting armature $7714 and wiper F2 in. any of the positions. 1-11. and strapping connection to. terminal I5 connected'with theupper side of the-impulse springs.

It will be. assumed. at this stage. that for the purpose of routing the call through to a toll line relay set. at the parent tandem exchange; it will be necessary for the register-controllerto transmit the routing digits 3148 and; these routing digits will be therefore transmittedin. response to the dialling of any of the pairsof. digitsOl-OQ indicative of a tollcall.

Considering now the stepping ofthe switchF by the impulse springs IMP2, itwillbe seenthat impulse springs IMPI. areineffective until wiper F2 reaches the 12th positionzwhen the short,- ci-rcuit is removed therefrom. Three impulses will be delivered to line during thetransitof .wiper F2 to position 15 and these serve in known man nor to raise the fi-rstcode selector wipers stolevel 3. The next four contacts on. the bank are strapped so that as the wiper stepsv over these contacts, the impulse springs again remainshortcircuited and bythis means an interdigital pause is provided. Thesucceeding codedigits .1, .41 and 8 are produced inlike manner the control of wiper FZbeing transferred to. wiper Ffiiwhen the wiper F2 leaves its bank and the call is routedto the tandem exchange via an .outging relay set.at the originating. xchange which will be shortly described.

When the F switch wipers Ffi reach position 40 all routing digits will have been sent out and-a circuit is therefore. completed over wiper F8.-in position 40; to operate relaySZ which looks at-its armature eel, disconnects-the driving. circuit to the magnet FM .at armature s22 and at armature s23 short-circuits theimpulsing spring IMPI and introduces into the outgoing loop. the. regenerator imp-ulsing springs IMP3.

At this stage of the call atoll line-relayset at the parent tandem exchange will have been seized and this relay set willbe endeavouring. to gain access. to one of axcommon group ofregistertranslators suitable. for routing. the; call to. the required outlying exchange. Inorderto prevent thegsendingi out. of; further. digits until. an idle routing. register translatorhas been: seized. it is arranged thatthe battery-connections to the line at the toll relay set are=normally such that relay D. will be inoperative.

When a free register-translator isfound, the battery connection. is-reversed so that rectifier MRA' becomes conductive and-rectifier MRB nonconductive and'relayD-now operates. Relay D in operating energises. relay. SS at armature d3, Wliereuponan energisingcircuit is completed for the regenerator transmitting magnet TM.

It will now be understood that the pin in the regenerator' which was displaced to mark. the termination of: the sending out. of the previous call is pushed out of thepath. of the sending disc and back to its-normal positionby, a resetting pin, designated RP-and. in circuit with relay P, but owing to the stepped head on the reset pin the sending disc'is not immediately released and: remains.held until magnet. TM is. de-energised. Magnet TM at its, contacts tm' disconnects relay P-which thereupon opens the magnet energising circuit at armature p2 and as fully described in McClew and-.woodlands Patent N0..2,188,461 the sending'discv is. releasedand rotates until the reset pin comes up against the stop pin indicating the; termination; of. the first train. of impulses received thereon.

Duringthe sending out. ofthe train, it will be noted; that since thezreset pin RP is not. connecting with any stop .pin such as-SP, relayP cannot be re-operated. while during this time the first digitreceivedv on the register-translator is sentout inregenerated. form by way of the impuls springs IMP-l controlled from the regenerator device and is delivered tothe routing reg:- ister-translatortaken inuse atthe tandem exchange.

On release of relay P it will be noted that a circuit is completedvia armature 102 for the slowto-release relay ISwhich-serves for the purpose of timin the subsequent. interdigital pause.

Previous to. and during this time, further trains ofv dialed'impulses may be. received on the receiving. disc and-it will-be appreciated that the two operations of reception of certain digits and retransmissionofearlier digits may go on simultaneously-but independently of each other.

When the, sending. disc comes. up; against the stop-pinindicating, the termination of the first train of impulses, relay, P is again operatedand relay IS is disconnected. After therelease time of. relay IS which determines the interdigital pause, the. sending magnet TM. again receives a momentary energization inorder. torelease the sending discv once more to generate asecond train ofimpulsesin the manner described.

When all thedigits. received have been retransmittedthe sending disc will catch up with the receiving disc; whereupon the off-normal contacts NI open and release-relay ON. Furthermore, if the. complete number-.has-be'en dialed and sent'out. correctly theroute-discriminator will receive. a-full set of digits for routing the call to the wantedparty and asa result the .batteryconnections tothe line conductorsare restored to normal so that relay Dreleases and extends-earth over armature dl; p3,- ss2 and 1292-, F. switch wiper F3-:or F! and bankarmature-onli to battery via relay C'O.

Relay COinope-rating at armature col :disconmeets the idle markingbattery'from theincoming P lead,- whereupon the wiper switchingrelay in the Adigit-tselector istreleasech This-relayin releas-

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