BE424495A - - Google Patents

Description

       

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  Improvements to telephone systems.



  The present invention relates to telephone systems in general, it relates more particularly to telephone systems in which long distance and local communications are established by means of automatic switches.



   The object of the invention is to provide an improved telephone system in which inter-city communications, passing through the position of a long-distance operator to terminate in an automatic office, can be established, via a line. long distance and through automatic switches located in a remote office, with the line requested in this office, the long distance operator performing the same actions when establishing a call through a remote office as when establishing

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 communication to a local line, it receives identical supervision in both cases.



   A further object is to provide new and improved circuit arrangements relating to the use of voice frequency current pulses for switch control and supervision.



   Another object of the invention is the development of suitable circuits for exchanging communications at great distances between automatic offices in which the automatic switches operate according to different control systems.



   Referring now to the attached plans, it can be seen that FIG. 1 is a map showing the relative location of several towns served by exchanges equipped with the new interurban system; that fig. 2 and 3 are junction diagrams representing the local and inter-city interconnections of the offices in Sao Paulo and Rio de Janeiro; that fig. 3 to 25, 28 and 30 to 34 are circuits and finally that FIG. 36 shows how the different figures must be arranged to form a logical whole.



   It should be noted that in fig, 1 the numbers surrounded by a circle and placed very close to the trunk lines indicate the number of trunk lines in the group.



   The offices in Campos, Sao Paulo and Santos are automatic offices in which are used switches with ascending and rotating movements which are actuated directly by the impulses corresponding to the numbers emitted, the office in Rio de Janeiro is an automatic office of the type "Rotary" in which one uses

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 switches controlled by reverse pulses as is done in automatic motor driven systems.



  The offices in Jundiahy and Campos are ordinary manual offices.



   Referring now more particularly to FIGS. 2 and 3 we will explain the junction diagram of the networks of Sao Paulo and Rio de Janeiro. Fig. 2 is the junction diagram of the Sao Paulo network, FIG. 3 is the junction diagram of the Rio de Janeiro network.



   Sao Paulo networks is a five-digit network, the first of these designates the office requested in the network, the last four digits designate the line called in the office considered. The offices in service are the second, third, fifth and eighth corresponding to the second, third, fifth and eighth levels of the primary selectors. Each of the offices is set up in a separate building and the intercity office is located in another building better located to serve as a terminus for the intercity lines.



   Long distance calls are made by subscribers when they send the digit "0". Primary selectors, such as OS1, are connected to trunks that start at the tenth level of these to end at the long distance office, one of these trunks is represented by T1, it extends through the junction circuit TC to the "inter-rapid" position CLR1 which is connected to a trunk position.



   An automatic long-distance office is employed in Sao Paulo. This office is represented by the cord circuit CC1 leading to one of the positions of the interurban office as well as by the bodies PE1 forming part of this position.



   To allow incoming calls in the office

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 from Sao Paulo and coming from Campinas, Rio de Janeiro and Santos to be routed automatically under the action of the impulses received through the interurban line used. , each of the trunk lines coming from these offices is provided with an incoming selector. The selectors TFS2, TFS3 and TFS4 are assigned to lines TL2, TL4 and TL3 respectively. These selectors can have their banks connected in multiple with those of the primary trunk selector TFS1, so that the digits received on these trunk lines cause a selection just like the digits received from the CC1 cord circuit of the Sao Paulo trunk office.



   Referring now more particularly to FIG. 3 We will now explain the junction diagram of the Rio de Janeiro office.



   The motor driven reverse pulse type automatic switches are represented by the TOS-2 switch of the long distance office, the primary switch OS-2, the thousands switch MS-2, the hundreds switch HS-2 and the final selector or connector C-2
Six-digit subscriber numbers are used in the Rio de Janeiro network. The network is divided into eight offices with a capacity of 20,000 lines, two call digits being reserved for each office, the two-digit group being the characteristic of a set of 10,000 lines.



  For example, the numbers 28 and 48 are assigned to the office to which the line of extension B ends as shown by the numbers 28 and 48 placed in the rectangle that represents the thousands selector MS-2.



   The Rio de Janeiro interurban manual office is represented by the CC-2 cord circuit, by the PE-2 units associated with it at one of the positions and by the jacks J-1 to J-5. The J-5 jack is associated through the

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 TLC-2 trunk line circuit to the TL5 trunk line that runs between Rio de Janeiro and Campos, the J-4 jack is associated with the "fast inter" circuit coming from a level of the primary selector via the CLR-2 circuit; jacks J-1 and J-2 are respectively incoming and outgoing jacks associated with the TL4 trunk line between Sao Paulo and Rio de Janeiro, the J-5 jack is associated with the finder F-4 through the circuit of line LC-1.

   When the long distance operator wants to establish a communication through the long distance trunk system to the line of a subscriber in Rio de Janeiro, she plugs into the J-5 jack, therefore she uses a finder, such as the F- finder. 4, to extend the connection to a primary trunk selector such as TOS-2. As it has its contact bank connected in mul- tiple with the banks of primary selectors such as OS-2, the TOS-2 trunk primary selector is able to extend connections through the regular selector train, consisting of from local and long distance switches to subscriber lines.



   To establish communications in the opposite direction, that is to say from Rio de Janeiro to Sao Paulo, it is necessary that the operation of the keys of the call keypad of the interurban office be registered and that the corresponding trains d. Decimal pulses are retransmitted to operate Sao Paulo's direct-operated switches. For this purpose a group of six recorders-transmitters, such as RS-1, have been provided for the twenty-five trunk lines comprising the TL-4 line. Each of these transmitters has a finder, such as F-3, which connects it to an interline through a pulse repeater such as IR-4.

   This recorder-transmitter receives the digits entered on the call keypad and retransmits the decimal pulses on the interurban line.

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   In order to allow the positioning of the selection devices, through the trunk lines, by means of current pulses at voice frequency, each automatic trunk line has a pulse repeater at each end, to which is associated a frequency conversion unit. This unit is a device which translates the pulses of direct current into corresponding pulses but at voice frequency (1000 periods) in the case of outgoing communications and which translates the received pulses into current at 1000 periods into current pulses. continuous capable of operating switches.

   In addition, each of the conversion units comprises the means making it possible to transmit and translate supervision pulses constituted by current at 1000 periods modulated by current at 60 periods. By "modulation" is meant any electrical modification to which an alternating current wave may be subjected and which results in a complex alternating current wave which can be decomposed into a number of alternating current waves whose frequencies are distributed on either side of that of the wave of the alternating current considered in the first place.



   A detailed description of the operation of the system will be given below.



   A. Call from Sao Paulo to Jundiahy.



   To describe how connections are made from the Sao Paulo automatic long distance office to a network served by a manual long distance office, it will be assumed that a subscriber of the Sao Paulo network (for example the subscriber of station A, fig. 2, office 8) wishes to get in touch with a subscriber that must be reached through Jundiahy's office, fig, 1.

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   1. Call to the Sao Paulo long distance office.



   The subscriber of station A picks up his receiver and is therefore connected to a primary selector, such as OS-1, of fig. 2 via finder F-2. When the subscriber issues the number "0" assigned to the long distance office, the primary selector OS-1 chooses a free trunk terminating at the long distance office via a trunk circuit, such as TC, which takes place in call position to extend the call through the T-1 junction to the long distance office via a "fast inter" circuit CLR-1 of figs. 2 to 4.



   When the junction circuit goes into the call position, relay 304 of the CLR-1 circuit attracts under the action of its two windings placed in series with the lower winding of relay 303. As a result of the high resistance of the winding - upper end of relay 304 (12,000 ohms) the current flowing in the junction T1 remains at / low value, the positive polarity being connected to the negative wire of the junction. At its top contacts, relay 304 places a negative on pin C 250 and the multiple of it to mark the CLR-1 line circuit as a calling circuit in the banks of researchers who have access to it.



   At its lower contacts, relay 304 closes at a circuit point of relay 301 which attracts and opens, / at its upper contacts, the response supervision circuit, at its lower contacts it places a ground on the common starting wire 307 to start the searcher who goes in search of the circuit.



   Starter wires such as 307 and 412 are connected to each other and extend through a suitable distributor so that grounding the common starter wire results in prolonging

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 -a starting positive to a position starting wire, such as 511, from one of the long positions.



   At each position of the long distance office, when an operator is not busy with something else, it is assumed that she has activated a conversation key of a free cord circuit such as the key K3, fig. 6. The relays 504 and 503 therefore attract in series. The relay 504 disconnects the lamp 507 and the relay 503 performs the preselection of the finder F-1 to put it into service and extends the conversation wires of the cord circuit CC1 to the members PE1 of the position. When the call occurs, ground is extended to wire 511 and the starter relay 501 circuit closes.

   Relay 501 grounds wire 511 to ignite lamp 508, it also closes the bias winding circuit of relay 502, a branch of this circuit operates the control solenoid 510 in a circuit of own order. The electromagnet 510 works as a buzzer and causes the searcher to search for the calling line circuit by the finder F-1 The relay 502 attracts when the pins 250 are reached, it disconnects the electromagnet 510 to stop the search by the searcher. Relay 502 also transfers relay 501 from wire 511 to ground; it turns on the brushes 500, negative, positive and as well as the brush, it bypasses its own test winding and connects the brush C-500 to the earth via the upper winding of 10 ohms of relay 504.

   The positive fed through the 10 ohm winding of relay 504 is sufficient to keep the circuit of fig. 4 against any commissioning attempt by another researcher.



   The group identification lamp 306 now lights up via the EC-250 pin and the EC-250 brush to let the attendant know the group of lines or trunks in which a call is received. there is a lamp

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 of this kind at each position for each group of lines on which calls can be received at the considered position.



   In the circuit of fig. 4, relay 302 attracts to disconnect relay 301 and to prepare a supervision circuit bypassing the upper 12,000 ohm winding of line relay 304, this circuit closes as soon as relay 301 releases, the value of the current in the son of the junction T1 then becomes sufficient to give the indication of occupation on the junction circuit TC so that the connection is maintained from the trunk position. Relay 303 does not attract because the sign of the polarity connected to the jumper wires is reversed. when the TC junction circuit is seized.



   In the office calling 8, fig. 2, the increase in the value of the current in the wires of the junction causes the sending of the distinctive tone which is sent when the circuit is seized to stop sending. Relay 305 has been incorporated so that the supervisory bridge can be cut again, when the operator wishes, when she activates her call key to cause a new and momentary sending of the distinctive tone if she wishes to hear a call. once again this tone.



   The operator who answers and whose headset telephone 590 is connected to the conversation wires of the circuit of this CC-1 cord now speaks with the calling subscriber and makes sure that the office of destination of the call is indeed Jundiahy.



  The operator then inserts her CD calling device into her lanyard circuit and issues the three-digit number assigned to Jundiahy's office.



   To associate the CD call device and the circuit, the attendant activates the key K-6 which prepares the circuit of relay 506, and closes the circuit of relay 522, When the

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 relay 522 attracts, it disconnects relay 521 and closes the circuit of relay 523? This relay attracts and blocks through the contacts of relay 525, it also establishes the circuit of relay 506. Relay 506 blocks without the help of the contacts of the key for inserting the call dial; it places an earth on wire C leading to the selector in fig. 7, it connects the previously prepared call bridge to the positive and negative conversation leads that terminate at the TFS-1 selector.



   In the TFS-1 trunk switch primary, connecting a ground to the incoming C wire results in placing a ground on the lower pin of the lower coil of relay 601 and causing relay 603 to be drawn.



  The relay 603 prepares the circuit of the ascent electromagnet 605 and its blocking circuit passing through its lower winding, finally it switches the rotation electromagnet off.



   At the same time, relay 603 draws in the circuit of wire C, relay 601 draws into the circuit of the conversation wire in series with the pulse contacts of the call device CD of fig. 6. Relay 601 closes the circuit of relay 602, which once again connects a ground to wire C; it prepares the circuit of the ascending electromagnet 605 and at one point opens the circuit of the releasing electromagnet 607; it turns on the bias winding, 1300 ohms, of relay 604; finally it connects the test winding of relay 604 to brush C-650 which prepares the test.



   2. Transmission of the interurban line number leading to Jundiahy
The operator then activates her CD call device in accordance with the digits which are assigned to the group of the desired long distance line. Each time the CD call device leaves its normal position, it closes contacts which establish the circuit of relay 522, in parallel.

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 with the lower contacts of the K6 key for inserting this device, therefore the attendant can return the K-6 key to the normal position as soon as she has turned the call device CD to send the last digit without that she has to fear a premature release.



   The TFS-1 trunk switch relay 601 operates under the action of the first pulse train emitted by the calling device CD and sends a pulse train to the ascent solenoid 605.



   When relay 603 releases at the end of sending the first digit it disconnects its lower winding and the ascending electromagnet at its lower internal contacts; at its lower contacts it closes the circuit of the rotation electromagnet 606. The rotation electromagnet 606 then functions as a buzzer and advances the brushes 650 on the pins of the chosen level.



   When a free selector is found, for example the TLS-1 selector in fig, 11, the test winding (the winding which is shown most upward) of relay 604 receives a negative via the brush. C-650 and pin C-1000 of fig, 11, this negative polarity is fed through contacts 1014 and the upper coil of relay 1003. When relay 604 attracts, at its lower contacts it opens the circuit of the rotation electromagnet 606 to stop the rotation movement, it also opens the circuit of the relay 602.

   Additionally, relay 604 extends the incoming EC wire to the EC-650 brush; it places an independent earth on the brush C-650 through the contacts of relay 603, which bypasses the test winding of this relay; it puts its median blocking winding under tension to give itself a clean blocking circuit leading to the incoming C wire; finally he disconnects the incoming conversation wires from the relay @

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 601 and extends them to the positive and negative 650 brushes.



  Relay 601 releases and prepares the circuit for releasing solenoid 607. Relay 602 releases as a result of the pull of relay 604 and releasing of relay 601. When relay 602 releases, it opens the relay. shunt placed across the test winding (upper winding) of relay 604; it cuts the bias winding circuit of relay 604 and removes the earth applied locally to the incoming C wire, however leaving that wire grounded, in the DC cord circuit, to the contacts of relay 506.



   The interurban selector TLS-1 of fig, 11 having been chosen, the relay 1003 attracts in the circuit borrowing the wire C grounded and the contacts 1014, the relay 1001 attracts in the circuit of the conversation wires and the contacts of pulses from the calling device. Relay 1002 attracts as a result of the attraction of relay 1001. Relay 1004 also attracts wire C and contacts of relay 1003 into the circuit.



   With relays 1001 to 1004 attracted, the TLS-1 trunk selector is ready for operation. Because the trunk lines to which the TLS-1 trunk selector has access are in relatively small groups, two-digit numbers are assigned to the group, so that two or more groups can appear in a single bank contact level.



   When the second digit of the desired number is sent, the calling device causes the momentary release of relay 1001, the desired number of times, The ascent electromagnet 1009 operates under the action of the pulses emitted by relay 1001 , the lower winding of relay 1003 keeping this relay attracted after cutting the circuit of the upper winding, at contacts 1014, at the first step of ascent of the switch.

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   At the end of the sending of the pulse train, relay 1003 releases and transfers the control circuit from the ascending electromagnet 1009 to the rotating electromagnet 1010.



     When the last digit is emitted, relay 1001 sends pulses to the rotation electromagnet 1010 which advances the brushes 1050 step by step until they engage on the group of contacts assigned to the group's first interurban line. Relay 1005 attracts in series with the electromagnet 1010 at the moment of sending the first rotational pulse, it disconnects the brush C-1050 and causes the relay 1005 to attract. The relay 1006 switches the brush B-1050 off. circuit and opens the blocking circuit of the relay 1004 which releases and prepares the own control circuit of the electromagnet 1010, this circuit becomes active at the end of the sending of the digit.

   The lower contacts of relay 1006 close a new rotation control circuit which is independent of the contacts of relay 1004;
At the end of the sending of the pulse train, relay 1005 releases and reconnects brush C-1050 to the test winding of relay 1008, moreover it releases relay 1006 to connect brush B -1050 to the test winding of relay 1007.



   If the first trunk line is busy there is no circuit that can attract relay 1008, so the own control circuit of rotation electromagnet 1010 closes and when releasing relay 1006 , the rotation solenoid 1010 operates in its own control circuit and advances the brushes 1050 stepwise over the bank contacts until a free trunk line is found, or until the pins of the last trunk line in the group are reached.



   If the TL-1 trunk line in fig. 2 and 5 is

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 free when brushes 1050 arrive at pins 460, the test winding of relay 1008 is fed through wire C, the relay attracts and opens its lower contacts to stop the rotational movement; it extends the positive, negative and EC wires to the circuit of the interurban line TLC-1, moreover it closes the blocking circuit of its middle blocking winding and places a ground on the brush C-1050. short
Relay 1001 releases and after an instant the relay 1002 also releases. The selector remains held in the working position by an earth brought through the wire C coming from the previous selector.



   In the circuit of the trunk line TLC-1 relay 409 draws in the circuit of wire C, it connects its own winding to pin C-450.



   3. Loop test and automatic call control.



   When the attendant has activated the CD call device to send the last digit, she gives the key K6, fig. 6, in the rest position and when the CD calling device reaches its normal position it releases relay 522 which connects a ground, through the 20 ohm winding of relay 521, to the negative talk wire to find a negative polarity, finally it closes the circuit of relay 524 through the contacts of relay 523. Relay 524 is provided with a weighted spring which vibrates for a certain time, after its armature has been attracted, so as to provide a delay , one second can be, before relay 525 attracts.



   Releasing relay 522 and initiating vibration takes place before relay 1001 has been disconnected as a result of pulling relay 1008 causing relay 521 to pull into the negative talk wire circuit. But as soon as the 1008 relay attracts and cuts the bridge

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 placed at the terminals of the conversation wires and that it extends them to the trunk line circuit TLC-1 the relay 521 releases and prepares the circuit of the relay 505.



   When relay 525 draws at the end of the delay period it releases relay 523. Relay 524 circuit opens to allow relays 524 and 525 to release; relay 506 blocking circuit opens to allow that relay to release after a short time. At the same time, the supply circuit of relay 505 closes.



  Relay 505 therefore attracts and blocks through contacts of key K-2. Additionally during the interval required for relay 506 to release, a call control pulse is sent from the negative pole of the battery through the 100 ohm resistor 526 to the positive talk wire. At this time a ground is connected to the negative talk wire to prevent unwanted operation of relay 404 in the negative talk wire circuit by inducing through the capacitor associated with the windings of the table translator coil 400.



   The primitive relay 505 drive circuit consists of normally closed contacts of relay 521, so relay 505 cannot attract if a line relay is still connected to the talk wire terminals, which can occur. when one of the switches in the selection train becomes defective and has not functioned or if the operator has neglected to send a sufficient number of digits to establish the circuit completely. If relay 505 does not attract, any partial connection is released when relay 506 releases which has the consequence of opening the loop and cutting off the earth connected to wire C and which extended to the primary trunk selector.



   In the TLC-1 trunk line circuit, fig. 5

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 the momentary call control impulse, transmitted by the components of FIG. 6, at the end of the emission of the pulses, comes from the operation of the relay 403 which sends, on the trunk line TL1, an inrush current taken from the common wire 414.



   4. Control of interurban line loopbacks.



   Usually each end is provided with a trunk line, provided with repeaters, with "loop" such as "loop" 413.



   When the TL-1 trunk line is in service and therefore relay 409 is pulled, the circuit of relay 401 closes through contacts of relay 402, although relay 402 is pulled, to prevent relay operation. 401. Relay 402 derives current from table-mounted trunk line components in a single circuit, assuming that there is current sent through the conversation wires connected to the trunk line, each of the circuits. used to connect the trunk line to a local line is provided with a 44,000 ohm resistor with center tap, as shown in fig. 4, through which current is sent to attract relay 402.

   The current flowing through relay 402 is not sufficient to draw relays 403 and 404, neither of them being as sensitive as relay 402 and each of them receiving only half of the current which circulates in the loop-back control relay.



   In the event that the first sending of inrush current does not elicit a response from the operator at the Jun- diahy office, the operator of fig. 6 can ring once again on the trunk line by activating the key K-8 after having activated the key K-4 to avoid sending the call control pulse to the CLR-1 circuit of fig. 4.

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   After the conversation key K-3 has been reset to allow the release of the relay 503, the relay 402 is kept attracted under the action of the circuit CLR-1 of FIG. 4.



   When communication has been established by the operator at Jundiahy's office the two subscribers can speak as they wish.



   5. Call back to the long distance operator by shaking the fork.



   If the local calling subscriber of set A wishes to attract the attention of the long distance operator, he can do so by lowering the fork of his device momentarily one or more times. Each time the fork is lowered the TC junction circuit in fig. 2, reverse the sign of the polarities applied to the wires of the TL-1 junction by reversing the direction of the current in the lower windings of the relays 303 and 304 of the CLR-l circuit, Whenever the direction of the current is reversed, the relay 303 draws to insert a resistor 309 of 2,000 ohms into wire C for the duration of the reversal, which reduces the value of the current by an amount sufficient to allow the release of relay 504. When relay 504 releases, it closes the 507 lamp circuit.



  When the direction of the current is brought back to normal, relay 303 releases and shunts resistor 309 again, so that lamp 507 goes out. The operator can get back in touch with the subscriber by activating the conversation key K-3. When the operator has answered and she has taken note of the subscriber's desire, she can restore the K-3 key to the normal position to allow the release of relay 503 which cuts the wires of her headset telephone, or else it can cut off the established connection and establish another if it notices that the call has not been routed to the desired called line.

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   6, Call back on the long distance line.



   If the operator at the Jundiahy office wishes to get in touch with the long distance operator at the outgoing office, she momentarily sends inrush current on the TL-1 long distance line, relay 407 momentarily attracts, it releases the relay 406 and therefore closes the circuit of the upper winding of the relay 408. The relay 408 closes the blocking circuit of its lower winding in series with the supervision lamp 509 which lights up instantly to attract the attention of the operator. When the latter answers, the relay 503 attracts to switch on its headset telephone, to cut the circuit of the lamp 509 and to release the relay 408.



     7. End of Communication.



   When the conversation is over and the receiver is hung up at the local station calling relay 303 pulls in to insert 2000 ohm resistor 309 into wire C Relay 504 releases to ignite lamp 507 immediately and give an end signal. In order to free the calling end of the established connection, the attendant momentarily actuates the key K-1, thereby opening the blocking circuit of relay 501 which releases and cuts the earth at a point in the wire. 311, it opens the circuit of relay 502 which releases and at another point opens the blocking circuit of relay 501, this relay therefore does not attract when the key K-1 is returned to the rest position.



   In the CLR-1 circuit of fig. 4, relay 302 releases and replaces the upper 12,000 ohm winding of relay 304 in the blocking bridge placed across the wires of T-1 junction so as to give end supervision on the TC junction circuit. As soon as the normal operation of the relays has taken place in the TC junction circuit

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 switches OS-1 and F-2 return to idle and the wires from junction T-1 are disconnected to cut off the sending of current. When this happens relay 304 releases followed by relay 303.



   Before releasing the called end of the established connection, the operator of fig. 6 can momentarily start inrush current on the TL-1 trunk line in order to give an end signal to the operator at the remote office.



  The called end of the connection is released when the operator momentarily activates the K-2 key. When this happens, relay 505 releases and turns on the wires leading to the long distance primary selector of fig. 7.



  Relay 505 also removes ground from wire 511 to turn off lamp 508.



   In the TFS-1 long distance primary selector in fig. 7, when ground is removed from incoming 0 wire, when relay 505 releases in the cord circuit, relay 604 releases, it turns brushes 650 off, and closes the circuit of release solenoid 607. A Similar release takes place in the TLS-1 long distance selector.



   In the trunk line TLC-1 circuit, removing the earth from wire C of junction T-2 terminating at terminals 460 makes the circuit accessible to other selectors and allows relay 409 to release and replace the circuit. in normal condition.



   8. Full occupancy at primary long distance selectors.



   If the TFS-1 trunk switch is not able to find a free junction in a desired level, the brushes rotate to full occupancy to operate a meter, there is a meter connected to each full occupancy contacts. Winding

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 Relay test 604 is supplied in series with the meter, the relay attracting connects the earth to brush C to cause effective operation of the occupancy meter. When relay 604 bypasses its test winding to apply direct earth to brush C, relay 603 pulls to carry the earth connection to brush C so that it borrows the upper middle contact of relay 602 instead. contacts of relay 604.

   So when the release relay 602 releases due to the pull of the relay 604 and the release of the relay 601 the earth is disconnected from the brush C-650 to leave the occupancy meter free to register other indications. before the TFS-1 switch has returned to idle. Relay 603 remains attracted through the upper winding of relay 604.



   In addition, the fully occupied contacts 612 connect the wire coming from the apparatus giving sixty pulses per minute to the wire EC to constitute a circuit causing the lamp 509 to flicker, when the relay 505 attracts, and thus to give an indication. visualization of the occupation of all junctions.



  The TFS-1 selector is released as described above.



   9. Total occupancy at manual interurban line selectors.



   If all trunk lines in the selected group are busy, the brushes continue to advance until they reach the last trunk line. Pins B and C of the last trunk line in the group are connected to each other in order to establish the drive circuit of relay 1007, so that wire C of the last trunk trunk line is grounded, as a result, relay 1008 cannot attract.

   Relay 1007 attracts under the action of this earth, it disconnects the brush C-1050 to prevent any subsequent attraction of relay 1008 when

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 that the brooms will pass on the trunk lines of other groups of the same level. When the switch reaches the eleventh position, the limit switches 1016 close which stops the operation of the rotation electromagnet 1010 and attracts the relay 1003 to give a momentary impulse. Additionally, contacts 1015 close to connect the signal wire to the EC wire to produce a supervisory lamp flicker on the calling side.



   This selector is released in the usual way by removing the positive connected to the incoming C wire, allowing relays 1007 and 1008 to be released.



   10. Blocking of a faulty manual trunk line.



   If the TL-1 trunk line is seized and found to be defective, the operator can cause it to be permanently blocked to prevent it from being taken at the Sao Paulo office, she alerts the test table by pressing the K- key. 4 and momentarily maneuvering the key K-7. The K-7 key places a positive on the lower talk wire and a negative through a 100 ohm 526 resistor on the upper wire.



  The lower coil of the relay 404 is therefore energized, it locks in series with the lamp 417 at the test panel 416.



  Relay 404 turns relay 403 off; it keeps the junction against any subsequent seizure by disconnecting wire C from junction T-2 by which the trunk line can be reached by the selector; it connects the common wire 415 of the guard tone to the conversation wires of the inter-city line to send a tone on this line, this tone will be perceived if the interurban line is seized at the other end. When the line is repaired, the relay 404 is released by opening the blocking circuit at the test panel, the lamp 417 goes out.

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   B. Communication from Jundiahy to Sao Paulo.



   We will now explain the different phases of the progression of a call made from Jundiahy to a line in Sao Paulo. When the TL-1 trunk line is seized at Jundiahy's office and inrush current is initiated on it, relay 407 pulls in and releases relay 406 which closes the circuit of relay 408. Relay 408 closes its own blocking circuit through its upper winding, it disconnects wire C from junction T-2 of relay 409 to prevent the seizure of the trunk line by the selectors, by removing from wire C the polarity marking the line as free . Relay 408 also places a ground on wire 412 to start a finder looking for 450 pins, it places a call polarity on pin C-450 as well as on the multiple of that pin by connecting relay 409 to the C-450 spindle.



   Seeker F-1 searches for the calling circuit.



  When brushes 500 come into contact with pins 450, relay 502 attracts and the consequences of this action have been discussed above.



   In the circuit of the trunk line TLC-1, the relay 409 attracts when this is found by the finder F-1, it unlocks the relay 408 and opens the starting circuit.



   After speaking to the long distance operator at Jundiahy's office and being notified of the destination of the call, the operator in fig. 6 returns the conversation key K-3 to the rest position and introduces the call device CD into the CCI cord circuit by activating the key K-6 as explained previously, then it emits the desired digits and replaces the K-6 key in rest position.



   The primary interurban selector TFS-1 operates under the action of the pulses of the first digit transmitted 2 and

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 searches for a free long distance office selector, such as the TOS-1 long distance office selector. Relay 901 attracts to attract relays 902 and 903.



   The line number of extension A being 84161, the digit 2. whose transmission is necessary to extend the connection to a long distance office selector, is followed by the number 84161.



   Relay 901 momentarily releases eight times and brushes 950 are driven to the eighth level of bank contacts. When relay 903 releases at the end of sending the pulse train it disconnects the ascent electromagnet 909 and turns on the rotation electromagnet to rotate the brushes 950 in search of a free trunk line between offices such as the one leading to the incoming TMS thousands toll selector. When this junction is reached, relay 904 draws and places a direct earth on the C-950 brush to keep the junction chosen against any subsequent seizure.

   Relay 904 also closes its blocking circuit through its guard winding at its upper interior contacts; it stops the rotational movement and prepares a blocking circuit at its lower contact, at its highest contacts it disconnects the incoming conversation wires from relay 901 and extends them to the conversation circuits (not shown) of the junction between offices which leads to the long distance selector of the thousands TMS of fig. 2.continues
When the following digits are output the connection as a result of the operation of the TMS thousand toll selector in fig. 2, the operation of a long distance selector hundreds such as THS and the operation of a combined local and long distance connector such as C-1 to extend the connection to the line at station A.

  <Desc / Clms Page number 24>

 



   If we admit that the line is free, the long distance selector of the thousands TMS reverses the direction of the current in the wires of the junction between offices which attracts the relay 906, this one short-circuits its line winding to remove it from the conversation circuit; it turns on the contact of relay 907, finally it attracts relay 905.



  The relay 905 closes its blocking circuit which passes through its lower winding, it introduces the windings of the translating coil 951 between the incoming conversation wires and the positive and negative brushes 950; it connects relay 908 to the incoming positive talk wire through the lower-left / windings of the translator coil 951. Relay 907 draws and makes a connection between the incoming grounded C wire and the incoming EC wire. Earth is therefore returned to the EC wire to power the lamp 509 of the CC-1 cord circuit when it is connected to the EC wire.



   It should be noted that the loop leading to the TOS-1 selector remains energized and that the connection protection is ensured through the right windings of coil 951 and through relay 907. Under these conditions, relay 521 in position d The operator releases and allows relay 505 to pull when relay 523 releases.



   When the automatic call control pulse is sent the TOS-1 toll office selector relay 908 momentarily pulls in to send the inrush current over the toll trunk and transmit it, intermittently as usual, to the called line.



   1. Line supervision.



   The earth placed on the EC wire causes the lamp 509 to burn to inform the operator of the state in which the connection is located.



   2. The called subscriber answers. '
When the called subscriber answers, the current does not flow

  <Desc / Clms Page number 25>

 no longer in the long distance trunk between offices, the connection remains maintained by the called subscriber during the course of the conversation. When this occurs the TOS-1 long distance office selector relay 907 releases and removes the ground of the EC wire associated with it, which turns off the lamp 509.



   It should be noted that relay 907, when releasing as we said above, closes the selector blocking circuit by applying a ground to wire C of this device so that the selector is not released if the attendant cuts communication on the called side if the receiver is still off hook at the called station.



   During the conversation, relay 402 remains attracted to keep the circuit of relay 401 open to keep the bypass on.



     # Callback of the operator by the calling long distance office.



   If the calling long distance operator wishes to call back the operator in fig. 6 At any time after communication has been established, it momentarily sends inrush current over the TL-1 trunk line to pull relay 407 and release relay 406. Relay 406 closes the circuit of relay 408. With relays 408 and 409 both attracted, resistor 410 of 2,000 ohms is inserted into wire C terminating at pins 450 which releases relay 504, the conversation key K-3 now being returned to the normal position. .



   It should be noted that relay 408 does not block when it pulls in in this case, which is the reverse of what happens under identical circumstances when the call is sent in the reverse direction. Therefore, relay 408 releases and disconnects the resistance from the circuit again.



  Relay 504 does not attract again when relay 408 releases and returns the current to its normal value because this relay is set such that it cannot attract in series with

  <Desc / Clms Page number 26>

 relay 409. Relay 504 being released, lamp 507 turns on and off when the operator manipulates key K-3 to attract relay 503.



   Relay 504 follows the movements of the switching fork when the finder scope is interconnected with the CLR-1 circuit. This occurs because the 500 ohm winding of relay 302 is shunted by 500 ohm resistor 308 which allows sufficient current to flow to pull relay 504 again under the action of its sound. 10 ohm winding after it released when resistor 309 was turned on. The absence of such a resistor bypassing relay 409 changes flicker supervision to straightforward supervision when finder F-1 is brought to pins 450.



   4, Releasing the connection.



   When the called subscriber hangs up his receiver, the train of switches of the called office causes the power cut in the wires of the junction between offices, which attracts relay 907 again, which again connects the grounded C wire to the wire EC which is associated with it and causes the lamp 509 to light, which gives the end signal.



   The operator of FIG. 6 can cut the connection by operating the keys K-1 and K-2. The F-1 finder and the TFS-1 trunk selector are released as previously described.



   In the TOS-1 office long distance selector relays 904, 905 and 906 return to idle due to the removal of ground from pin C-900 when the preceding selector is released. The release of the relays 904 and 905 cuts the blocking circuit borrowing the brushes 950, negative and positive, to allow the release of the selectors of the called office.

  <Desc / Clms Page number 27>

 



   5. Call to a manual office in Sao Paulo.



   At least one of the offices in Sao Paulo is of the manual type with call announcers. Although positions equipped with call annunciators can provide standard supervision of long distance communications, there is an unavoidable delay between when it appears and when the attendant can insert a plug into the jack of the called line and transfer it. therefore put line supervision towards the caller.



  To satisfy this special condition, the upper winding of relay 905 is connected to the incoming EC wire when relay 904 attracts. CC-1 Cord Circuit Relay 506 places a ground to the EC lead through an 1800 ohm resistor.



  Relay 905 then pulls under the direct control of the trunk circuit cord to cause switching and thereby allow relay 521 to be released and the relay circuit 505 closed.



   6. Total occupancy in a long distance office selector,
If all the junctions to which the TOS-1 trunk selector has access on the chosen level are occupied, the brushes are brought to the fully occupied position. When they have reached this position the contacts 916 disconnect the upper winding of the relay 905 to prevent this relay from inadvertently drawing into the circuit of the EC wire, the operations. later are in principle identical to those which have been described except that the supervision by flickering is returned from the common wire giving the supervision pulses through the contacts of relays 904 and 905 attracted and the wire EC to flash the lamp 509 of the junction long distance.



   The TOS-1 selector is released when ground is removed from its incoming C wire to allow release of relays 903 and 904.

  <Desc / Clms Page number 28>

 



     7. Calls to busy lines.



   When the called line is occupied the connector which must establish the link finds the pins occupied at the time of the test, the direction of the current is reversed in the junction line between offices and interrupted at the rate of 120 times per minute, that is to say , at a rate double that of the jitter when all the junctions are occupied as described previously. If the TOS-1 interurban office selector of FIG. 10 is turned on, the reversal of the current has the effect of attracting relay 906 which attracts relay 905 as previously described.



  Then the pulling and intermittent release of relay 907 at the rate of 120 times per minute causes a rapid and characteristic flicker of lamp 509 to alert the operator that the called line is busy.



   Under these conditions, when the attendant cuts the connection, the selectors return to idle as previously described because the TOS-1 inter-city office selector releases between two successive operations of relay 907. The switches of the called office return to operation. in normal position due to the opening of the loop when the TOS-1 selector is returned to its place.



   C, Communication from Rio de Janeiro to Campos,
It can be assumed that the subscriber of set B in FIG. 3 wishes to get in touch with a Campos subscriber.



   When he picks up his receiver his line is connected through a finder, such as finder F1, to an office selector, such as OS-2, and a recorder-transmitter, such as RS-3, is associated with the receiver. connection circuit through a finder scope such as F-6. When the subscriber transmits the characteristic Rio de Janeiro digit, the OS-2 selector is set under the control of the transceiver to transfer.

  <Desc / Clms Page number 29>

 the call to the long distance office through the CLR-2 circuit.



  The recorder-transmitter is then released.



   Referring to fig. 33 we can see that the call lamp associated with the J-4 jack lights up, the attendant then inserts the AP answer plug, of a free cord circuit, into the J-4 jack. The call light goes out.



   The operator activates the key K-9 to attract the relay 2002 which separately extends the two ends of the cord circuit towards the components of the position shown in fig. 34 and disconnect the third wire from the AP plug of the 2001 lamp and substitute a resistance of 500 ohms.



   When she learns that the call is intended for the Campos office, the operator tests the jacks, such as the J-3 jack, as usual, using the CP plug.If we assume that the J-4 jack has been found free, it pushes the CP plug into it, the relay 2109 attracts, it disconnects the test lead 2110 and connects the TC lead to the station 2190.



   The Campos office is called by sending the inrush current over the trunk line in a manner identical to that which has been described in the case of fig. 5. When the Campos operator answers, she takes note of the desired number and establishes communication. The 2001 and 2003 supervision lamps are reconnected to the body of the AP and CP plugs respectively when the attendant puts the K-9 key back into the rest position to release the 2002 relay.



   At the end of the conversation, the interurban operator receives the end signal at one or the other of the two lamps 2001 and 2003 or at both lamps at the same time.



   D. Communication from Campos to Rio de Janeiro.



   It can be assumed that the call comes from Rio de Janeiro through the TL-5 trunk line to terminate at the TLC-2 trunk line circuit of Fig. 33. The line lamp

  <Desc / Clms Page number 30>

 illuminates to give a call signal and an attendant inserts the AP answer plug of a free cord circuit into jack J-5.



   The operator activates the K-9 key to associate her 2190 telephone with the circuit in question under the action of the 2002 relay. When the operator has read the desired number, she inserts the CP call card in a free jack such as the J-5 jack. Relay 2001 then draws in series with relay 2109.



   When the 2011 relay attracts, a tag is sent to the searcher bench, such as F-4 in fig. 3, and the relay 2010 circuit closes, thereby a finder, such as F-4 in fig. 3, goes in search of the La-1 line circuit. The attendant then activates the key K-12 to disconnect the TC and RC wires from her telephone and to connect them to the T and R wires of the 2100 call keypad, but she does not activate these keys until the 2104 lamp lights up.



   When finder F-4 arrives at pins 2050 the 2013 relay pulls in to open the starter circuit, but the 2012 relay is not pulling at this time.



   The operation of the F-4 finder is accompanied or followed by the operation of a finder, such as F-5, which connects a recorder-transmitter, such as RS-2, to the connecting circuit. When these two seekers have completed their functions, relay 2103 attracts and closes the circuit of lamp 2104 which lights up. The negative of a 24 volt battery and the positive of a 60 volt booster battery are connected to the keys of the keyboard through resistors, therefore so called "weak" or "strong" pulses of both polarities can be sent on the two wires according to a combination chosen from those given in the table in fig. 35.



   After sending the digits, the operator gives the

  <Desc / Clms Page number 31>

 K-12 and K-9 keys at rest to release the 2002 relay.



   When the link is established and the requested line is found free, supervision is returned to the body wire. This causes more intense current to flow through the S-500 pin and the 2013 and 2012 relays.



  The latter attracts and bypasses the 1700 ohm winding of the 2011 relay to light the 2003 lamp and inform the operator that the connection has been established to the called subscriber's line and let him know that this line is free. Sending of inrush current takes place as described above.



   When the called subscriber answers, the current in the plug body wire is reduced again to cause the release of the 2012 relay and reinsert the 1700 ohm lower winding of the 2011 relay to turn off the 2003 lamp.



   When the conversation is finished and the called subscriber hangs up his receiver, the value of the current in the body wire of the plug of the established connection is increased again to light the lamp 2003. The attendant then sends the end signal to TL-5 trunk line and cut the connection.



   1. Sending of the occupancy indication.



   If the called line is busy, an intermittent busy indication is given by lamp 2003, but if all the trunks in the desired group are busy, the jitter rate is only 60 pulses per minute.



   E. Communication from Sao Paulo to Rio de Janeiro,
In this case the subscriber of the Sao Paulo office calls the trunk table through the CLR-1 circuit of fig. 2 and 5, it is answered by means of the CC-1 cord circuit of FIG. 6.

  <Desc / Clms Page number 32>

 



   1. Transmission of the long distance line number to
Rio de Janeiro.



   The operator introduces the CD calling device into the circuit as described above and sends the digits (4 and 6) assigned to the Rio de Janeiro office followed by the digits of the subscriber's line number in the office from Rio de Janeiro.



   The TFS-1 primary interurban selector operates under the action of the pulses of the first digit (4), it raises its brushes to the fourth level and keeps them connected to the terminals of a free trunk selector, terminals 800 of the TLS-2 trunk line selector in fig. 9, for example. When this selector is entered the relays 801 and 803 attract followed by the relay 802.



   The next digit is repeated through a contact from relay 801 to the rotation solenoid 808.



   Relay 804 draws, at the first step upwards, to open at a point the control circuit of the automatic ascent which supplies the electromagnet 808. The relay 804 remains attracted, during the ascent, to prevent the ascending. premature attraction of relay 805 when test brush 821, during ascent, passes over grounded contacts. The relay 803 also remains attracted during the vertical movement.



   2. Research the level.



   At the end of the sending of the pulse train, the brushes 850 are in front of the sixth level. Relay 803 releases with a certain delay and prepares the circuit, for automatic level search, of the ascent electromagnet 808, at the same time it opens the primitive circuit of relay 804.



  The relay 804 releases or not at this moment depending on whether all the junctions of the sixth level are occupied or not, If all these junctions are occupied, the relay 822 is attracted,

  <Desc / Clms Page number 33>

 it removed the earth from the sixth level test contacts in the banks of all brushes, such as 821, switches with automatic trunk line access. There is therefore no blocking circuit for relay 804 or supply circuit for relay 805 through brush 821 and relay 804 releases to send an additional pulse to the electromagnet of climb 808, the switch rises to the next level where the same busy test recurs.



   If there are one or more free junctions in the chosen level, relay 822 is not attracted and when relay 803 releases and the primitive supply circuit of relay 804 is cut, the latter remains momentarily drawn in series under the action of its winding connected in series with the upper winding of relay 805. Relay 805 draws in series with relay 804, it closes its blocking circuit which borrows its lower winding and ends at the earth taken at the contacts of the relay 802. The relay 805 also opens at another point the automatic control circuit of the ascent electromagnet 808 and it establishes the own control circuit of the rotation electromagnet 809. The brushes 850 do not rotate at not looking for a free junction.



   At the first step in rotation, the brush 821 is released from the vertical test bench and the circuit of relays 804 and 805, connected in series, is cut. Relay 804 releases but relay 805 remains attracted by the action of its blocking circuit.



   3. Commissioning of the IR-2 repeater.



   Assuming that the TL-4 trunk line associated with the IR-2 repeater, fig, 12 to 15, is free, when brushes 850 arrive at pins 1100, the upper test winding of relay 806 is placed in the circuit. which includes the negative taken through relay 1105 and the contacts of the

  <Desc / Clms Page number 34>

 relay 1105, 1113, 1125, 1121 and 1120. The relays 806 and 1105 draw in series and the relay 806 opens the circuit of the electromagnet 809, it shunts its own test winding to place a direct earth on the brush 0 -850; it extends the incoming EC wire to the IR-2 repeater and disconnects the incoming conversation wires from the 801 relay windings and extends them to the IR-2 repeater. Therefore the relays 801, 802 and 805 release.



   In repeater IR-2, relay 1105 attracts with a certain delay due to the shorted winding which is connected in series with the lower winding when this relay is energized. When relay 1105 attracts, it closes the circuit of relay 1103 which draws into the incoming line circuit but relay 1102 is not attracting at this time because it is a differential relay.



   The relay 1105 also successively attracts the relays 1106 and 1107. When the relay 1107 attracts it places an earth on the wire 1150, and puts the supervision relays 1109 to 1111 under the control of the relay 1123; it removes the earth from one of the contacts of each of the relays 1123 and 1124 to remove the relay 1131 from the influence of these relays.



   4. Send the activation pulse on the trunk line.



   In order to send a commissioning pulse on the TL-4 trunk line the relay 1107 closes, at its lower contact, the circuit of relay 1127 which attracts and at its lower contact temporarily blocks to the blocking wire 1150 independently. contacts of relay 1113. Relay 1127 also closes the circuits of relays 1128 and 1129. Relay 1128 prepares the emission of the start-up pulse by opening the circuit of the conversation wires to prevent the emission of this pulse to the translator coil 1175 and the wires 1162, it removes the earth from the

  <Desc / Clms Page number 35>

 wire 1200 to transfer the TU-2 vocal frequency current generator apparatus from the receiving position to the transmitting position.



   Transmit relay 1129 connects wires 1161 of cable 1200 to trunk line TL-4; it attracts the sequence relay 1113; it closes the circuit of the auxiliary relay 1130 and places a ground on the wire 1167 of the cable 1200.



   In the device TU-2 vocal frequency current generator, of fig, 16, the relay 1202 releases and a voltage of half a volt at 1000 periods brought by the wire 1242 is connected to the control grid 1211 of the A two-way amplifier lamp, this causes a 1000 period component to be superimposed in the circuit of the plate through the impedance 1206 connected to the 130 volt source providing the plate current. At the same time, wire 1241 connected to a 40 volt, 60 period source connects to the second grid of lamp 1211 to modulate the current of the plate by means of the 60 period current. As a result, a current of 1000 periods modulated at 60 periods is passed through the capacitor 1226 of the circuit of the plate and the primary winding of the step-down transformer 1217.

   The current supplied by the secondary of this transformer passes through contacts of the released relay 1202 and ends up at the output wires 1161, then through contacts of the relay 1129 drawn to the wires of the TL-4 trunk line. .



   At the end of sending the start pulse, when relay 1130 attracts it closes the circuit of relay 1131, which attracts after a very short time and opens the circuit of relay 1127. Relay 1127 releases after a short moment and opens the circuits of relays 1128 to 1130 therefore relays 1128 to 1130 release followed by relay 1131.



   Relay 1128 closes the wire circuit again

  <Desc / Clms Page number 36>

 conversation and attracts relay 1202 again.



   Relay 1129 disconnects wires 1161 and also removes ground from wire 1167 allowing relay 1201 to draw into a circuit comprising contacts of relays 1113, 1101, 1105, 1109 and resistor 1142.



   Before describing the sending of the selection pulses, a detailed description will be given of the apparatus for generating voice-frequency currents TU-2.



   5 The TU - 2 vocal frequency current generator,
The vocal frequency current generator comprises the lamps 1211, 1212, 1213 and 1214. The lamps 1211 and 1213 are each provided with a filament supplied at a nominal voltage of 6.3 volts at which they consume 0.3 A.



  Lamp 1212 is a double diode which functions as a differential detector. This lamp has a two-section filament that requires a potential difference of 6.3 volts to pass through / to a current of 0.3 amps.



   Amplifier 1214 has a filament supplied at 25 volts to allow 0.3 Ampere to pass. All the filaments of these lamps are supplied in series in a circuit comprising the resistor 1225 of 4 ohms, the contacts of the key 1237 placed normally in position working, the negative pole of the 48 volt office battery connected through relay 1233. This relay is normally energized but it can release and close the signal lamp 1236 circuit in the event that one of the lamps is removed from it. its socket or that its filament is burnt or cut.



   Lamp 1211 is used as a two-way amplifier, it is used as an output amplifier for signal transmission on TL-4 trunk line. The screen grid is connected to the positive pole of a source at 130

  <Desc / Clms Page number 37>

 volts, supplying the circuit board current, through 50,000 ohm resistor 1227 which is shunted by 0.1 MF capacitor 1228. Between the control grid and the plate is shown the auxiliary grid which can be connected either to the earth or to the source of 40 volts - 60 cycles by means of wire 1241, depending on the state in which is found. relays 1201 and 1202.



   For the reception of the signals the primary winding of the step-up transformer 1224, of ratio 1 to 30, is connected to the reception wires 1162 through two capacitors.



  The secondary winding of this transformer is normally switched on to act on the voltage applied to the control grid of lamp 1211, a negative bias voltage, 1.2 volts, being applied to the control grid of lamp 1211. lamp 1211 to account for the drop of 1.2 volts in the 4 ohm resistor 1225.



   With relay 1202 attracted as it should normally, the secondary winding of transformer 1217 is connected to the terminals of wires 1243 and 1244.



   It should be understood that when the 1000 period current is modulated by a 60 period current the resulting signal comprises frequencies of 940, 1000 and 1060 cycles. In order to correctly receive these signals, chokes 1219, 1221 and 1223 and capacitors 1218, 1220 and 1222 have been grouped together and connected between wires 1243 and 1244. Choke 1222 and capacitor 1223 are tuned to a frequency of 1000 periods, choke 1221 and capacitor 1220 are tuned to a frequency of 1100 cycles in principle. The choke 1219 and the capacitor connected to its terminals to constitute a detour circuit are granted, in principle, to 100 periods.

   The currents at 1000 periods will therefore flow through the inductor 1223 and the capacitor 1222; the currents at 1060 periods flow through choke 1221 and the condenser

  <Desc / Clms Page number 38>

 capacitor 1220 but will not pass through capacitor 1218 due to the presence of the circuit trap. The currents at 940 periods will however flow through the capacitor 1218 since the trap circuit is not tuned at this frequency and through the inductor 1221 since the value of the capacitor 1218 is such as with the inductor 1221 it forms a circuit tuned, in principle, to 900 periods.



   The pulse amplifier 1213 check grid as it is connected to the filament circuit is normally connected to the negative of a 20.1 volt bias battery which represents the voltage drop at through filaments 1213, 1212 and 1211 and through resistor 1225 of 4 ohms. This grid bias is given to the control grid of lamp 1213 through the 0.6 megohm mid-tap resistor comprising sections 1229 and 1230, each section of the resistor being shunted by a 0.1 MF stabilizing capacitor. wire 1244 is connected to the middle tap of the grid resistor, the negative voltage of 20.1 volts is normally applied to each of the plates of the differential detector 1212.

   The cathode associated with the plate connected to coil 1223 is also supplied by a negative bias voltage of 20.1 volts.



   The cathode associated with coil 1221 is connected to the filament circuit at a negative voltage point, hence the plate connected to coil 1221 is normally less negative by 18.9 volts than the cathode associated with it so that no Current does not flow through the left side of the differential detector until the bias voltage of 18.9 volts is compensated.



   During the reception of a signal, the existence of a voltage at 1000 periods at the terminals of the coil 1223 causes the birth of a current which circulates in the cathode and the anode

  <Desc / Clms Page number 39>

 of the lamp 1212 in series with the section 1229 of the gate resistor, the upper terminal of this resistor is therefore made more positive than the lower terminal, correspondingly reducing the negative voltage normally applied to the control gate of the lamp 1213.

   On the other hand, when the signal contains a component at 900 periods or at 1100 periods sufficient to create, at the terminals of the coil 1221, a voltage capable of compensating for the bias voltage of 18. 9 volts, a current flows in the section. left of 1212 through the lower section 1230 of the gate resistor and therefore makes the midpoint of this resistor more negative than the lower terminal thereof due to the voltage drop across section 1230.

   So when we receive a signal other than the one we expect and which falls in the neighborhood of 900 periods or 1100 periods, the current flowing through the coil
1221 and the section of the differential detector which is associated with it and which passes through the section 1230 tends to make the grid of the lamp 1213 more negative than normal, which prevents the operation of the lamp 1213 under the action of the signal itself if it contains a component with 1000 periods which in other circumstances would be active.



   When the TU-2 generator apparatus is to be used to receive select pulses from a remote office relay 1214 pulls to substitute relay 1203 for delay coil 1207 in the lamp plate circuit 1213.



   The signal amplifier, 1214, is designed to amplify the 60 period modulations received on the pulse amplifier plate 1213, it is a pentode whose control gate is normally negatively biased at 20.1 volts across the 100,000 ohm gate resistor 1232. At this bias voltage, a plate current

  <Desc / Clms Page number 40>

 large enough circulates in the circuit of the lamp plate, through the impedance coil 1208, it comes from the source at 130 volts. The 0.1 MF 1231 coupling capacitor is used to couple the plate of lamp 1213 to the control grid of lamp 1214.



   After amplification, the signal pulses pass through relay 1205 via capacitor 1234 of 0.3 MF, it is chosen as well as the winding of relay 1205 to constitute a resonant circuit with approximately 60 periods to prevent the operation of the relay at receiving selection pulses.



   The 0.006 MF capacitor 1235 is intended to divert from relay 1205 the carrier current at 1000 periods, amplified and one half-wave of which is rectified, because it has been found in practice that otherwise this voltage at 1000 periods, amplified, is high enough to cause disturbing discharges.



   The description will now be given of the establishment of a communication from Sao Paulo to Rio de Janeiro.



   6. Transmission of selection pulses on the trunk line.



   When the call device CD in fig. 6 for sending the next digit after entering the trunk line TL-4 and the IR-2 pulse repeater, releasing relay 1103 when sending the first digit closes the circuit through the earth taken from the contacts of relay 1107, the contacts of 1101 and 1109 and the lower winding of relay 1128. This lower winding is very powerful, it attracts relay 1128 without any delay.



  This relay cuts the receive wires 1162 and removes ground from wire 1166 to allow relay 1202 to release. Relay 1201 also attracts, it follows that a current at

  <Desc / Clms Page number 41>

 1000 periods, unmodulated, circulates in the transmission wires 1161. The relay 1104 is supplied in parallel with the relay 1128 through the contacts of the relay 1105. Because it is delayed on attraction, the relay 1104 remains attracted. while sending the pulses, at its lower contacts it closes its blocking circuit borrowing its upper winding.



   As a result of each release of relay 1103, the circuit of relay 1129 closes at the internal contacts.



  Relay 1129 draws and sends a momentary pulse of 1000 period current (through transmit wire 1161) over the trunk line each time relay 1103 is released.



   At the end of the sending of the pulse train, relay 1104 releases and opens the circuit including the upper winding! relay 1128 which releases. In addition, relay 1129 releases and consequently relay 1202 also releases to put the device back in the reception position.



   Each of the remaining digits is transmitted over the TL-4 trunk line in the same way.



   7. Removal of current in the loop.



   When the relay 522 in the equipment shown in fig. 6 releases as a result of placing the K-6 pulse sending key in the rest position and the return to the normal position of the CD call device at the end of sending the last digit, the opening of the wire loop positive and connecting the negative wire to earth through relay 521 causes imbalance of relay 1102 which attracts and closes the circuit of relay 1101. When relay 1101 attracts it closes its blocking circuit and disconnects the earth from lower contacts of relays 1103 and 1104.

   Relay 1101 also disconnects wire 1150 from the internal contacts of relay 1103; it disconnects the resistor 1142 of the wire 1167 to release the relay 1201 of the apparatus generating the currents at vocal frequencies;

  <Desc / Clms Page number 42>

 it disconnects the relays 1103 and 1102 from the terminals of the incoming conversation wires; it finally extends the conversation wires to the left windings of the translator coil 1175, thereby relays 1125 and 1126 are placed under the control of the conversation wires.



   8, Transmission over the trunk line of the pulse causing the inrush current to be sent.



   When the pulse causing the inrush current to be sent is automatically transmitted through resistor 526, relay 1126 attracts and causes relay 1127 to be drawn followed by relays 1128, 1129 and 1130. Consequently a current pulse with 1000 periods, modulated at 60 periods, is transmitted over the trunk line in a manner identical to that described for the start-up pulse.



   During the time taken by relays 1127 to 1131 to complete one cycle of operation, the inrush send pulse transmitted to relay 1126 has ended and relay 1126 has released.



   The IR-2 repeater remains in this state until the connection has been extended to the called line in the Rio de Janeiro office; a supervision pulse is then received on the trunk line.



   How the devices in the Rio de Janeiro office operate when the trunk line is put into service and the inrush current selection and send pulses are issued will be explained below.



   9. Commissioning of the CR code transmitter.



   The apparatus TU-4 of fig, 17, generator of currents at vocal frequencies is identical to the generator apparatus TU-2 of fig. 16, so that when the arming pulse, with 1000 periods modulated at 60 periods, is received by the TU-4 device, this pulse activates the signaling relay, when the device arrives TU-4

  <Desc / Clms Page number 43>

 corresponding to relay 1205 of the TU-2 device. As a result, wire 1463 is momentarily grounded and relay 1423 momentarily pulls. Relay 1423 closes the circuit of relay 1431 which attracts but has no effect at this time. A branch of this circuit extends to relay 1404 which draws to prepare the circuit for relay 1419.



  Relay 1423, signal repeater, also opens the circuit of relay 1421, delayed in operation, and closes the circuit of the lower coil of relay 1420 which is a differential relay, storing energy. A relatively large current is established in the lower winding of relay 1420 while the reverse current which passes through the upper winding of this relay is somewhat reduced due to the presence of the 300 ohms connected in series. in this winding. As a result, energy is stored in the lower winding of relay 1420, but the relay does not attract as long as the circuit remains closed through the two windings whose effects are opposite.



   When the momentary start-up impulse is terminated and the relay 1423 releases, the energy stored in the relay 1420 causes the attraction of the latter under the action of the induced current flowing in the two windings connected in series when the primitive circuit is cut. When relay 1420 attracts, it closes its blocking circuit through its two windings connected in series. At the same time the associated resistor is connected so that the relay does not draw too high a current to remain blocked. Relay 1420 places a ground on blocking wire 1450 and a ground on wire-1451.



   To put the code transmitter in fig. 23, 24 and 25, which has been preselected, relay 1420 closes the circuit of the lower winding of relay 1419 which therefore attracts and

  <Desc / Clms Page number 44>

 prepares its blocking circuit, borrowing its lower winding, through the upper contacts of relay 1420, at the same time relay 1437 attracts, it blocks by means of wire 1450.

   Relay 1457 connects the head and neck wires T and R of cable 0-1 to the head and neck wires T and R of the line circuit of fig. 33; it transfers the head and neck wires associated with relay 1419 of the head and neck wires leading to the line circuit of FIG. 33 and connect them to pulse wire P, cable C-1 and body wire S respectively; it places a ground on wire 0 of cable 0-1, this wire ends at the CO-1 relay passing through the relay 101. The CO-1 relay is a differential relay, it is not attracting at this time, but relay ICI attracts and prepares its blocking circuit which closes at the time of the subsequent release of relay 1501.

   The ICI relay also extends the head, neck and pulse wires of the C-1 cable to the transmitter and the head, neck and pulse wires of the / code CL-1 circuit. Relays 1604 and 1606 draw in series, in the circuit of the pulse wire in series with the top winding of relay 1419, to keep the loop closed.



   Relay 1605 closes the circuit of relay 1606, these relays together remove the earth of the ground wire C which opens the wire blocking circuit 1501. Relay 1501 therefore releases to allow the preselection of the next code transmitter. and to allow release of CAl relays.



  CB1 and CC1 The ICI relay is now blocked through contacts of relay 1501, relay C01 attracts under the action of its lower winding and remains attracted to keep cut the extension of wire 0 of cable C-12 which prevents in service of another code transmitter via this channel.



   10. Guard of the interurban line in Rio de Janeiro.



   It also results from the attraction of relay 1420

  <Desc / Clms Page number 45>

 a negative is placed on the S body wire terminating at jacks J-2, through which long distance calls are made, to mark the jacks as busy jacks.



     11. Commissioning of a long-distance office selector.



   Relay 1422 is connected to the S body wire terminating at relay 2021 of the LC-2 line circuit, fig. 33.



   Relay 2021 draws in this circuit but relay 1422 does not draw. Relay 2021 closes the circuit of relay 2010 for the purpose of starting a finder, such as F-4 in fig. 3 to find pins 2000.



   12. Commissioning of the pulse receiver relay.



   Relay 1419 also places a ground on the wire
1466 leading to the TU-4 apparatus, fig. 17, to cause the operation of the relay corresponding to relay 1204 of the TU-2 device. This relay attracts and switches on the incoming pulse relay corresponding to relay 1203 of the device.
TU-2.



   Relay 1419 also attracts relay 1418 to connect wire 1468 to wire 1432 and cause the circuit to be released if the select pulses are not sent. At its lower contacts, relay 1418 extends earth to the windings of relay 1409. Relay 1409 is a differential relay, storing energy.



     13 Receipt of selection impulses: cut of the end of communication signaling wire.



   The pulses of alternating current enter the device. TU-4 through 1462 receive wires.



   For each current pulse at 1000 periods, unmodulated, received on wires 1462, the relay of the TU-4 device corresponding to the 1203 relay of the TU-2 device transmits a momentary pulse to the 1424 relay, through wire 1464. The first time relay 1424 attracts it closes the relay circuit
1416, who draws to close his preliminary contact. At the time

  <Desc / Clms Page number 46>

 from releasing relay 1424, relay 1416 draws at the second time to cut wire RD, sending the end of communication, which leads to the incoming line circuit of fig. 32, this prevents the lighting of the 1907 lamp.



   At each momentary attraction of relay 1424, the circuit which borrows wire P to end at relay 1605 is cut. Relay 1419 remains engaged while sending pulses because relay 1404 is operating while receiving pulses.



   14. Control of selection pulses.



   When the received digit has been returned to the code transmitter, relays 1604 and 1605 release. Relay 1605 immediately draws back into the P pulse wire circuit when this circuit closes again, but usually relay 1604 does not draw again while receiving a pulse train because its 10 ohm winding has only a small number of turns, but it attracts again at the end of the sending of the pulse train.



   When relay 1605 releases for the first time it closes the circuit of relay 1607 which attracts and remains attracted while sending the pulses. It places a ground on wire 1650 which closes the circuit of relay 1621.



   In addition, each time relay 1605 is released, the circuit of relay 1608 closes. When relay 1608 first pulls it locks in series with relay 1611 through the 1650 grounded wire.



   When relay 1605 releases at the end of the first pulse, it cuts off the primitive circuit of relay 1608, but the latter remains momentarily attracted by the action of its blocking circuit which includes the upper winding of relay 1611. relay 1608 has a fairly hard setting but the spring tension is insufficient to release the

  <Desc / Clms Page number 47>

 relay immediately after its circuit is cut by relay 1605.



   When relay 1611 attracts it locks out via grounded blocking wire 1650. Because relay 1611 remains attracted it cuts off its original circuit and transfers the power wire to the next control relay 1612. As relay 1608 is about to release as a result of the high tension given by the springs it re - loose when its circuit is transferred from one control relay to another. During this transfer all current must cease in the winding of relay 1605 and this relay will release before current can be restored following transfer of the circuit to the next control relay.



   In order to understand which functions are fulfilled by the control relay and the relays 1615 and 1616, the manner in which they behave during the sending of a train of ten pulses will be described below.



   The numbers 1 to 4, surrounded by a circle and placed next to relays 1611 to 1614, show that these relays operate when the first four pulses are sent; the numbers 5 to '8, surrounded by a circle, show that these relays are still operating when the next four pulses are sent; finally the numbers 9 and 10, surrounded by a circle, show that the relays 1611 and 1612 operate for the third time when the ninth and tenth pulses are sent respectively.



  * At the end of the second, third and fourth pulse, relays 1612, 1613 and 1614 draw in the blocking circuit of relay 1608 and relays 1612 and 1613 extend the power wire to the next control relay as described for relay 1611. However when relay 1614 attracts it opens the blocking circuits

  <Desc / Clms Page number 48>

 relays 1611 to 1613 which release.

   When releasing relay 1611, the lower winding of relay 1615 is connected in parallel with the blocking winding of relay 1614, thus relay 1615 attracts and blocks directly through wire 1650 , at the same time it prepares new blocking circuits for relays 1611 to 1613, moreover it transposes the blocking circuit passing through the lower winding of relay 1614 so that it includes the upper contacts of relay 1612 .



   Relay 1611 attracts again at the end of the fifth pulse, it locks up through contacts of relays 1615 and 1613.



   When relay 1612 draws again at the end of the sixth pulse it closes its blocking circuit through its lower winding in parallel with that of relay 1611 and cuts the blocking circuit of relay 1614 at its upper contacts, which allows to this relay to release.



   When relay 1613 attracts again at the end of the seventh pulse, it blocks through contacts of the attracted relay 1615 and transfers the blocking circuit of relays 1611 and 1612 to its lower contact so that they remain blocked. in the circuit passing through the lower contacts of relay 1614, the internal contact of relay 1615, the middle contact of relay 1613 attracted, wire 1650 grounded.



   When relay 1614 draws at the end of the eighth pulse it goes off and cuts off the blocking circuit of relays 1611 and 1612 to allow them to release so that they can draw again on the ninth and tenth pulses. When relay 1611 releases, the circuit of relay 1616 closes in parallel with the blocking winding of relay 1614, this circuit borrows the contacts

  <Desc / Clms Page number 49>

   upper contacts of relay 1611 and the upper contacts of relays 1613, 1614 and 1615. Relay 1616 closes its own blocking circuit at its upper contacts, at its lower internal contacts it prepares a new blocking circuit for them. relay 1611 and 1612.



   Relay 1611 draws again at the end of the ninth pulse in the train, relay 1612 draws again at the end of the tenth pulse, each relay closing its own blocking circuit through wire 1650.



   15, Recording of received digits.



   Operation of the control relays prepares the circuits through code wire 1651, AB, and code wire 1652, CD, to transfer the temporarily stored digit to the first of six DS-1 registration devices through DS-6 of fig. 24. The transfer takes place only after all the pulses have arrived and after the relays 1604 and 1605 have pulled, so the relay 1617 attracts when it cannot attract during a pulse train due to its retardation characteristics. The attraction of relay 1617 takes place before relay 1617 releases.

   Relay 1617 establishes a multiple connection to earth for wire 1650, at its lower contacts the transfer takes place through code wires 1651 and 1652 to relay pairs A and B, C and D of the DS device. -1 digit record. These four relays are arranged to be drawn according to a combination chosen from a group of ten in order to register any number in a set of ten numbers, this combination is reproduced in fig. 27.



   To allow the selective operation of relays A and B via the code 1651, A-B wire, a positive polarized sensitive relay was taken for relay A and a

  <Desc / Clms Page number 50>

 unpolarized marginal relay for relay B. Likewise, relay C is a positive polarized sensitive relay while relay D is an unpolarized marginal relay.



   When you want to attract relay A through wire 1651 without attracting B, you send a weak positive pulse through this wire, but a pulse is emitted from the positive pole of a 60 volt battery through a resistor. 150 ohms when you want to send a strong positive pulse to attract relays A and B together.



  On the other hand, when it comes to attracting B without attracting A, a strong negative impulse is sent to this relay.



  In an identical manner, by sending weak and strong pulses of the desired polarity, the selection of relays C and D is made or they are attracted together.



   The table in fig. 26 shows the combination of relays which attract under the action of a train of pulses corresponding to any number taken between 1 and 0 and the character of the pulses transmitted on the code wires 1651 and 1652.



   When relay 1607 releases, relay 1617 circuit opens, this relay releases with a slight delay. When the relay 1617 releases, it disconnects the code wires 1651 and 1652, at the same time it removes the earth from the wire 1650. At this moment the relays of the group 1611 to 1616 which have drawn are released; relay 1621 attracts under the effect of the energy accumulated in its lower winding. When relay 1621 attracts it locks up through wire 1662.

   It disconnects the 300 ohm resistor normally inserted in the circuit to decrease the current consumption, and to allow the relay to release without delay it extends the 1650 power wire to the junction of the two windings of the relay. 1622; it disconnects the wires of code 1651 and

  <Desc / Clms Page number 51>

 1652 of the relays of the DS-1 digit registration device and extends them to the DS-2 device, identical to DS-1 and represented by a dotted rectangle.



   16. Transfer of stored digits.



   In the same way the following digits are temporarily recorded and transferred to the recording devices DS-2 to DS-6. Researchers, such as F-4 and F-5, fig. 3, have during this time connected a group of four receive relays (identical to the relays of the RG group, fig. 28) to the head and neck wires, a circuit therefore closes from the selected recorder-transmitter to the wires of head and neck T and R of the code circuit CL-1, fig. 25, and the ground which is connected to neck wire R through two of the receive relays is active enough to cause relay 1636 to draw in series with the 4,000 ohm resistor.

   The current flowing through relay 1636 at this time is insufficient to attract the recorder-transmitter relays connected to the neck wire and to impede their release if they have worked.



  When relay 1636 attracts, it extends the earth, taken at blocking wire 1600, up to wire 1660. Under these conditions, as soon as the second digit of the number has been received and registered the earth taken at wire 1660 is extended up to wire 1661 and relay 1635. When relay 1635 attracts it locks up through wire 1661, it temporarily connects wire 1660 to grounded wire 1600, it opens the circuit of relay 1633 and closes the relay circuit 1634.



   In addition, relay 1635 connects the head and neck wires T and R of the recording devices DS-1 to DS-6 to the head and neck wires T and R of the code circuit CL-1 for the purpose of transmitting by this route the same combination of pulses as that which was received through the code wires 1651 and 1652. This is shown in the table of fig. 27.

  <Desc / Clms Page number 52>

 



   When relay 1633 releases, when turned off by relay 1635, it disconnects relay 1635 to complete sending the pulse.



   When relay 1635 releases it closes the circuit of relay 1631. When relay 1631 attracts, it locks up through wire 1600 and places a guard polarity on wire 1633 at the same time it removes a guard polarity. wire 1662. Relay 1621 then releases and transfers the blocking circuit of relay 1622 to wire 1663. In addition, relay 1621 transfers the head and neck wires T and R, from the relay contacts of the device DS-1 to registration of digits, to the working contacts of the DS-2 registration device to prepare for the transfer of the second registered digit.



   Relay 1633 pulls again when releasing relay 1635 to prepare the circuit for pulse relay 1635 when gap relay 1634 releases.



  When relay 1635 attracts again, it transmits the combination of the code set by the DS-2 device, furthermore it opens the circuit of relay 1633 and closes the circuit of relay 1634.



   Relay 1635 again closes the circuit of the upper winding of relay 1632 which attracts and prepares its own blocking circuit through its lower winding and transfers the circuit of relay 1631 so that it passes. by contacts of the attracted relays 1632 and 1635 and leads to the wire 1600. Under these conditions, when the relay 1635 releases after releasing the relay 1633 it again opens the circuit of the relay 1634 and makes the relay 1652 attract again, moreover , it closes a new blocking circuit through the lower winding of relay 1632, at the same time it opens the primitive circuit of this relay, which passed through its upper winding, and it opens the transfer circuit of relay 1631.

   Relay 1631 therefore releases and transfers the earth

  <Desc / Clms Page number 53>

 from wire 1663 to wire 1662. When this occurs relay 1662 releases and transfers the head and neck wires T and R from the contacts on the DS-2 device to the contacts on the DS-3 device.
At the same time, relay 1622 transfers the blocking circuit of relay 1633 so that it encompasses the grounded wire 1662.



   At the end of the transfer of the sixth and last digit, releasing relay 1635 has the effect of closing the blocking circuit of relay 1632 and opening the blocking circuit, transferred, of relay 1631, this allows the release of the relay
1631 which transfers ground from wire 1663 to wire 1662. In this instance relay 1626 releases and disconnects wire 1660 from wire 1661 to prevent re-pulling of pulse relay 1635 when spacer relay 1634 releases.



     The RS-2 recorder-transmitter, fig. 3, having received the full number of digits, advances its sequence switch (not shown) to disconnect the head and neck wires from the code receiving relays. When this occurs, relay 1636 releases and at an additional point opens the circuit of relay 1635 to prevent any further attraction of that relay during the current communication.



   17. Recording of the inrush current sending pulse.



   In the IR-4 repeater, when the 1000 period current pulse, modulated at 60 periods, is received through the trunk line, relay 1423 draws into the circuit the signaling wire 1463 coming from the TU-4 device. , fig, 17, at its lower contacts it causes the attraction of the relay
1404, and it closes the circuit of relay 1415. Relay 1415 therefore attracts and locks to wire 1450, at the same time it prepares the circuit of relay 1414.



   To prevent the transfer of any indication that might have been established by the control relays

  <Desc / Clms Page number 54>

 of fig. 23, if relay 1424 follows 60 period modulation, relay 1415 at its lower contacts introduces 1000 ohm resistor 1441 into the wire, connected to earth, of the loop of the pulse circuit which results in the output - CR code reader. When this resistor is turned on, relay 1604 releases but the current in the loop remains above the value necessary to attract relay 1605. As a result, relay 1617 cannot attract and put the wires of code 1651. and 1652 in circuit.



   18, Transmission of the supervision pulse,
The circuits associated with the IR-4 repeater remain unchanged when the indication to send the inrush current is registered by the drawn relay 1415, until the connection has been extended to the called line and until 'until a supervision signal has been received. As the current increases through the 2023 and 2022 relays, it reaches a sufficient value to allow the 2022 relay to attract and cause an increase in the value of the current in the 2021 relay by bypassing its lower 1700 ohm winding. Relay 1422 therefore attracts and transfers the line of the working contact from the lower spring of relay 1410 to the idle contact to open the circuit of relay 1409.

   When this circuit is open, relay 1409 attracts and closes its blocking circuit, through its two windings in series, via wire 1450. Relay 1409 disconnects the 600 ohm resistor 1443 from the terminals of the right windings of the translator coil 1475; cuts the circuit of the relay 1433 which releases and allows the relay 1434 to attract through the blocking wire 1450, finally it prepares the power supply circuit of the relay 1410 through its two windings so that this relay can attract under the action of the next pulse.

  <Desc / Clms Page number 55>

 



   In addition, the attraction of relay 1422 opens the loop which is extended through the upper winding of relay 1419 and the impulse wire to the code transmitter of fig. 23, 24, and 25. Relay 1419 almost immediately releases and removes ground from wire 1466 to turn off the incoming pulse relay of the TU-4 device. Relay 1418 now releases to prepare the circuit for switching relay 1417.



   The attraction of relay 1422 also has the effect of closing the circuit of relay 1427 which attracts relays 1428, 1429 and 1430. A current pulse at 1000 periods modulated at 60 periods, is therefore transmitted on the wires of transmit 1461 in a manner identical to that described for the repeater IR-2, the end of the pulse being placed under the control of relay 1431.



   The relay 1428 also closes the circuit of the relay 1417 which attracts and blocks through the wire 1450, it disconnects the relay 1404. In addition, at the internal contact of the relay 1450, the circuit of the two windings of the relay 1410 closes. Energy is therefore stored in this relay, which prepares its attraction for the moment when its primitive circuit is open, when the relay 1430 releases at the end of the cycle of operations. When relay 1410 attracts it disconnects the circuit of relay 1427 from the closed, grounded contact of relay 1422 and transfers this to the non-grounded, ungrounded contacts of the same spring, which prevents attraction of relay 1427.



   The attraction of relay 1417 during the transmission of the supervision pulse also has the effect of partially extending the talk circuit to its highest springs, it cuts the blocking circuit of relay 1437 which releases and it disconnects the 0 wires. , T, P and R of cable 0-1 of

  <Desc / Clms Page number 56>

 IR-4 repeater, thereby terminating the association established between the CR code transmitter and the IR-4 pulse repeater. When this happens the CO-1 relay of the PS preselector in fig. 22 releases, but nothing happens after this release because the CA-1 relay has released, as we said previously, to disconnect the CO-1 relay from the ICI relay.



   19. Release of the CR code transmitter.



   In the CR code transmitter, when relay 1605 releases the relay 1606 circuit opens. Relay 1606 releases soon after, it removes the earth connected to the blocking wire 1600 and the polarity connected to the special blocking wire 1654 which allows the release of all the relays which drew in the CR code transmitter. The relays 1607 and 1608 release after the release of the relay 1606. The earth is replaced on the ground wire G of the transmitter of code CR which prepares the subsequent attraction of the relay 1501.



   20. Retransmission of the inrush current sending pulse.



   In repeater IR-4, relay 1417 opens the blocking circuit of relay 1415 and closes the circuit of relay 1414, through contacts of relay 1415, relay 1414 momentarily pulls. It opens the head and neck wires ending in the switch train and places a negative on the head wire through the 1444 500 ohm resistor, at the same time it applies a ground to the neck wire to prevent unwanted attraction of the wire. relay by induction in the neck wire R. Under the action of this momentary connection of an earth to the lead wire T, the inrush current is automatically sent to the called line in the usual way.

   With relay 1417 pulled in and relay 1437 released, the talk circuit is extended from the trunk line, through translator coil 1475, to the LC-2 line circuit of FIG. 33. Relay 1433

  <Desc / Clms Page number 57>

 Now draws into a circuit including the talk wires, it disconnects the circuit from relay 1434. Relay 1434 reinserts lead 1460 into the circuit to adapt the trunk line to interconnect with a subscriber line.



   21. Reception of the supervision pulse.



   In the Sao Paulo office, the 1000 period current pulse, modulated at 60 periods, transmitted by the IR-4 repeater in Rio de Janeiro causes the attraction of relay 1205 which connects a ground to wire 1163 to make attract relay 1123 which closes the circuit of relay 1109. This relay stores energy when the impulse is received, it attracts when the impulse is terminated, at this moment its blocking circuit is closed, it borrows its two windings. Relay 1109 disconnects 500 ohm resistor 1142 and places a ground on the incoming EC wire, in addition it transfers the power wire to relay 1116.

   The earth placed on the incoming wire EC is returned to ignite the supervision lamp 509, so the operator serves the position of fig. 6, is informed that the connection has been extended to the called line which is free and has been switched on. The automatic call of the called line having been activated, the attendant must not activate his call key to perform this maneuver,
22. Supervision of the response,
When the called subscriber answers, the well-known supervision takes place through the selection train of the called office and the current which flows through relays 2023 and 2022 of the LC-2 line circuit of fig. 33 is reduced again by an amount sufficient to release relays 2022 and 1422.

   The earth is then extended to relay 1427 to cause the attraction of relays 1427 to

  <Desc / Clms Page number 58>

 1430 which carry out the transmission of the supervision pulse. This is recorded in the IR-4 repeater by the attraction and blocking of relay 1411 when relay 1430 releases at the end of the cycle. Relay 1411 also closes the circuit of relay 1412 which attracts to unblock and release relays 1410 and 1411.



   In the Sao Paulo office, when this supervision signal is received, relay 1123 pulls and closes the coil circuit of relay 1110. Relay 1110 draws at the end of the signal and locks, earth is disconnected from the EC wire. incoming call to turn off the supervision lamp 509 of the long distance position to notify the attendant that the call has been answered.



   The conversation can now begin through the connections that have been made.



   23, End supervision.



   When the conversation is over and the Rio de Janeiro subscriber hangs up his receiver, the current in the body wire increases again by an amount sufficient to attract relay 2022 of the LC-2 line circuit, Fig. 33. When this happens, repeater IR-4 relay 1422 draws again, it closes relay 1427 circuit to cause a supervisory pulse to be sent on trunk TL-4. At the same time as this pulse is sent, relay 1410 attracts again to transpose the circuit of relay 1427 from the on contact to the off contact of the spring of the relay 1422.



   At the Sao Paulo office, the supervision pulse is received as before except that relay 1111 attracts at the end of the pulse instead of relay 1110. Relay 1111 closes the circuit of relay 1112 which attracts and opens the circuit of blocking of relays 1110 and 1111 which release followed by relay 1112. Relay 1110 being released an earth is applied

  <Desc / Clms Page number 59>

 again on the incoming wire EC through contacts of relay 1109. Lamp 509, giving supervision of the calling side in the long distance office, turns on again and gives the end of communication signal.



   24. Release of organs.



   The operator can cut the connection by activating her release keys K-1 and K-2, which releases the CC-1 cord circuit of fig. 6 and the TFS-1 primary interurban selector in fig. 7 as described above.



   In the TLS-2 trunk line selector, fig. 9, when earth is removed from pin 800-C when selector TFS-1 returns to idle, relay 806 releases and disconnects brushes 850, at the same time it closes the circuit of release solenoid 810. When the electromagnet 810 is attracted, the brushes 850 are returned to the normal position in the usual manner.



   In the IR-2 repeater relay 1105 drops due to removal of ground from pin 1100-0 when the previous TLS-2 switch returns to idle. Following the release of relay 1105, relay 1106 releases and makes its weighted spring vibrate with a decreasing amplitude, therefore relay 1107, delayed in operation, remains attracted for about a second, at the end of the operation. this period he relaxes.



   Note further that relay 1105 disconnects its windings from the incoming 0 wire when it releases and keeps them off as long as relay 1113 remains attracted. In this way, the TL-4 trunk selector remains kept in Sao Paulo until the transmission of the release signal is completely terminated.



   When relay 1105 releases and relay 1107

  <Desc / Clms Page number 60>

 is still attracted earth is connected to the drive circuit of relays 1128 and 1129. When relay 1128 pulls, wire 1165 is disconnected to allow relay 1202 to be released and current to be sent to 1000 periods, modulated to 60 periods, on the transmission wires 1161, the relay 1201 having been released following the attraction of the relay 1101 at the end of the sending of the selection pulse. When relay 1129 pulls, transmit wires 1161 connected to trunk line TL-4 wires to transmit the release extended pulse on the trunk line.



   At the end of the time interval determined by the setting of relays 1106 and 1107, relay 1107 releases and again opens the circuit of relays 1128 and 1129, which allows these relays to release and the generating device to high frequency tone to place itself in receive condition. Relay 1107 also removes ground from blocking wire 1150 allowing relays 1109 and 1113 to release.



   The JR-2 repeater is now in normal condition, it is marked as free repeater at pin 1100-C and multiples thereof as a result of the connection of release relay 1105 to wire C at the time of release of sequence relay 1113.



   In the Rio de Janeiro office when the extended release pulse is received, relay 1423 attracts for a sufficiently long time to allow relay 1421 to release, this in addition to causing the release of the relay 1415, cuts the blocking circuit of relay 1420, this one releases and removes the ground of wire 1451 and relay 1416 releases. When relay 1423 releases at the end of sending the release pulse, ground is removed completely from wire 1450 allowing relay 1417 to release. Relay 1421 attracts again when its circuit closes after releasing relay 1423, it again prepares the circuit for

  <Desc / Clms Page number 61>

 blocking of relay 1420. Relay 1431 releases after releasing relay 1423 and relay 1409 releases after removing the earth from wire 1450.

   At its lower contacts it again closes the local circuit of relay 1433 which keeps this relay attracted locally.



   The IR-4 repeater is fully released at this time.



   When the body wire S, terminating in the LC-2 line circuit of fig. 33, is cut at the contacts of relay 1417, relay 2021 of the line circuit LO-2 releases and allows relays 2022 and 2023 to release, the selectors of the selection train to return to idle and the calling line to return to free.



   25. Special precautions in the event that the called party shakes the pitchfork of his station.



   Interestingly, IR-2 repeater relay 1131 and IR-4 repeater relay 1431 each have a contact in one of the conversation wires. This is to prevent pulses from being sent to the receiving wires of the high frequency current generating apparatus when the called party shakes the fork of his post. It has been found in testing that these current pulses tend to paralyze the two-way amplifier so that wiggling the fork while sending the sustained release pulse will interfere with release.



   An overview will now be given of some additional features which have not been mentioned in the foregoing description.



     26. Total occupancy at the TLS-2 selector.



   If there is a case of full occupancy at an automatic trunk line selector, such as the TLS-2 selector, fig. 9, which is a level search selector, relay 822 draws, through wire 823, into a

  <Desc / Clms Page number 62>

 Chain circuit comprising contacts of chain relays, such as relay 1135 of fig. 12, so that the brush 821 is not able to find a ground to attract the relay 805. As a result the ascent electromagnet 808 attracts again to raise the selector brushes up to the next level. The seventh level is also provided with a relay, with a / such as relay 822, but such a relay is not provided for the eighth level, because this level is the last of the group of junctions characterized by the number 6.

   The eighth contact of the vertical test broom 821 bank is connected directly to earth, therefore the relay circuit 805 is always closed when the selector is moved to the eighth level during its search.



   If a free junction is not found in this level, the brushes turn to the end of their travel, the fully occupied contacts 815 close and cause relay 803 to be drawn in series with relay 806 again. control of the rotation solenoid 809 opens at the lower contacts of relay 806.



   The relays 801 and 802 release when the relay 806 attracts, the relay 806 remains attracted by the action of its middle winding inserted in the incoming C wire. Relay 803 remains drawn through the incoming, grounded C wire in series with the top winding of relay 806 and through contacts 815.



   During the time required for the release of relay 805 a count pulse is sent, through contacts of relays 802 and 803, to brush 850-C. Supervisory pulses are sent back to the incoming wire EC through full busy contacts 814 to notify the calling trunk operator that the entire trunk group is busy.

  <Desc / Clms Page number 63>

 



   When the previous selector releases and removes the earth from the incoming C wire, the relays 803 and 806 release, thus the selector is returned to the rest position by the normal operation of the release solenoid 810.



   27. The PS preselector.



   The operation of the preselector PS of fig. 22 and its cooperation with the repeaters with which it is associated will be explained more fully below. When the code transmitter is put into service, it is known that the earth, marking the transmitter as free, is removed from the G ground wire and the blocking circuit of relay 1501 is cut. When relay 1501 releases, the ICI relay blocking circuit closes. Likewise after the attraction of relay 1501, relays cAl, CB-1 and CC-1 release to disconnect the supply wires of the 25 repeaters from the 25 relays associated with the circuit of the CL-1 code transmitter. at the same time the earth is extended to attract the next group of connection relays associated with a free code transmitter.

   When each of the first five preset relays has released and the relay
1506 is the only one that remains attracted, the chain circuit is extended through contacts of the attracted relay 1506 to attract the connection relays CA-6, CB-6 and CC-6. These relays switch on the 25 supply wires of the 25 relays associated with the OL-6 code transmitter circuit and including relays 106 to 2506. The preselector remains in this state until the call is called. next is received and the sixth code transmitter is activated.



   Although the time required for the transmission of digits to the code transmitter and for the transfer of these to the recorder-transmitter is only a small part of the time taken for the establishment of a long distance call. it is quite possible that one or more of the five

  <Desc / Clms Page number 64>

 Previous code transmitters was released before the sixth device was put into service. In order to preselect the code transmitters again to see if they have become free, relay 1507 releases when all the preselection relays 1501 to 1506 are in the normal position, it extends the supply circuit to each of the relays 1501 to 1506 in order to completely attract again each of these relays which is associated with a free code transmitter.

   At this moment these relays only attract at the first time and at the preliminary contacts of relay 1501 the circuit of the lower 2000 ohm winding of relay 1501 is closed, this winding becomes active if there is an earth, indicating that the device is free, on the ground wire G of the transmitter CR. Under these conditions, relay 1501 completely attracts and again attracts relays CA-1, CB-1 and CC-1. A similar operation is performed for the preselection relay associated with the other free code transmitters. The main relay 1507 attracts again to cut the supply circuit of the upper windings to make relays 1501 to 1506 and to / release all the relays which only attracted at the first time.



   Relay 1508 normally draws under the control of main relay 1507 and ordinarily when relay 1507 releases it draws again almost immediately because one or more of relays 1501 to 1506 performs a preset.



  However, when all of the code transmitters are on at the same time, as may occasionally occur, relay 1507 does not immediately pull in but remains released until one of the code transmitters becomes. free.



  Under these conditions, the CAB, CBB and CCB relays attract as a result of releasing relay 1508. These relays being drawn in, the 25 power wires are extended to the 25 relays, 1CB to 25CB, occupancy, thereby the appropriate relay among

  <Desc / Clms Page number 65>

 this group, attracts if a call is received while the connecting circuits are busy.



   As soon as a connection circuit becomes free, a relay, such as relay 1501, pulls fully to pull relay 1507 again. Relay 1508 pulls again to release relays CAB, CBB and CCB. Note that alarm wire 1509 remains connected to ground to give an alarm signal while all connection circuits are busy and relay 1508 is released.



  It can now be assumed that a call is received on the TL-4 trunk line when all code transmitters are on and therefore relays 1508 is released and relays CAB, CBB and COB attracted. All the preset relays are released and the associated groups of three connection relays are released as well.



   28, Total occupancy at Code transmitters.



   When the arming pulse is received by the IR-4 repeater, when all the code transmitters are busy, the functions performed by the relays are performed as described previously.



   When the code transmitter on relay 1437 attracts, the power wire 0 of the C-1 cable is grounded and since all the code transmitters in service and the relays CAB, CBB and CCB are attracted, this closes the circuit of relay 1CB which passes through the upper coil of relay CO-1. Relay 1CB is blocked and as a result the upper winding of relay CO¯1 is short-circuited which allows the relay to attract under the action of its lower winding and cut the supply wire.



   The 1CB relay also connects wire 1510, giving the wobble occupancy, to the body wire S of cable C-1, thereby the positive polarity pulses initiated on the

  <Desc / Clms Page number 66>

 body wire S, at a rate of 60 per minute, causes the attraction of relay 1422 and its release sixty times per minute. These pulses are preferably of short duration so that the application of the earth to the body wire S is of insufficient duration to release the relay 2021 of the line circuit LC-2.



   As no blocking circuit is closed, by the intermediary of the impulse wire P of the cable C-1, through the upper winding of the relay 1419 the latter releases after the release of the relay 1409 and after its release the earth is disconnected from wire 1466 which terminates at the TU-4 apparatus; it also allows relay 1418 to release and relay 1409 to attract.



   When relay 1422 attracts, in. the circuit of the body wire S of cable C-1, it extends the earth to relay 1427 which attracts and causes the emission on line TL-4 of a supervision pulse, of current modulated at 1000 periods, as previously described. Relay 1417 pulls when relay 1428 pulls, it closes its own blocking circuit and cuts the blocking circuit of relay 1437 which releases. The CO-1 relay of the PS preselector releases at this moment because the power wire 0 of the cable C-1 is no longer connected to the earth, however the relay 1CB remains attracted, through the blocking wire L of the cable C-1, to keep relay 1422 connected to wire 1510.

   Relay 1410 receives a pulse through the contacts of relay 1430, it attracts when releasing relay 1430 to disconnect the circuit of relay 1427 from the contacts' at work of the spring of relay 1422 and transfer them to the idle contact . If relay 1422 is released, pulling relay 1410 has the effect of preparing a new excitation circuit for relay 1427.

  <Desc / Clms Page number 67>

 



  This circuit remains open, however, for a determined time, under the control of relay 1431 which is provided to introduce, between the transmitted pulses, sufficient spacing. to allow proper control of the pulses at both ends of the trunk line.



   When relay 1431 releases, relay 1427 attracts again to transmit a new supervision pulse. While sending this additional pulse, the circuit of the control relay 1411 closes, it pulls when the relay 1430 releases at the end of the pulse, as described previously. When relay 1411 releases, release relay 1422 attracts to release relays 1411 and 1410, relay 1410 prepares to send an additional supervision pulse on the trunk line during the momentary pull of the relay. supervision 1422.

   With relay 1422 pulling in and releasing at a rate of 60 times per minute, 120 pulses are transmitted, per minute, on the TL-4 trunk line since a supervisory pulse is sent each time relay 1422 attracts and another every time he releases.



   In the Sao Paulo office, when relay 1123 first attracts supervision pulses and then releases, relay 1109 attracts and blocks; relay 1110 attracts under the action of the following supervision pulse and relay 1111 attracts under the action of the third pulse to cause its release and that of relay 1110 under the action of release relay 1112, it is It follows that the relays 1110 and 1111 follow the alternating pulses, the relay 1110 releasing each time the relay 1111 attracts.



   When relay 1109 attracts, the circuits passing through the contacts of relay 1103 open. At the same time,

  <Desc / Clms Page number 68>

 relay 1109 cuts the line relay bridge and closes the conversation wires through the windings of the translator coil 1175 by removing the 600 ohm resistance from the artificial loss 1143. In this way, the current flows through the loop on which the pulses were emitted, ceases immediately upon receipt of the first pulse from the supervisory pulse train.



   If we assume that the call comes from the interurban table of FIG. 6, we can see that when the attendant has finished sending the digits and has returned the key K-6 to the rest position, the conversation circuit closes and if the attendant has left her conversation key K -3 in the working position so that the wires of her headset telephone are connected to the conversation wires, she hears the pulses, of current at 1000 periods modulated at 60 periods, which are sent on the trunk line. On the other hand, if the attendant has returned her conversation key K-3 to the rest position, the lamp 509 is connected to the EC wire of the connection established and the lamp flickers under the action of the intermittent current flowing through the EC wire.



   When the attendant activates the release key, she releases relay 505 and the primary selector. trunk TFS-1, trunk line TLS-2 selector and repeater IR-2 return to idle as described above, at the same time an extended release signal is emitted on trunk line TL-4 to release devices at the far end.



   In the IR-4 pulse repeater, if a supervisory pulse is sent from Rio de Janeiro to Sao Paulo at the time the release pulse begins, the release pulse is not registered until for relay 1427 to release and allow relay 1428 to release

  <Desc / Clms Page number 69>

 and reconnect wire 1465 to ground to place the amplifier of the TU-4 device in the receive position.



  When this occurs, relay 1423 attracts and opens at one point the circuit of relay 1427 to keep this relay off during the entire transmission of the release pulse without having to take into account an attraction. relay 1422. Relay 1423 also closes the circuit of relay 1431 which attracts and opens the circuit of relay 1427. The set of relays for sending the release pulse is set so that the pulse of release is long enough to cause release even if it is somewhat shortened, when transmitted, because a pulse is received on the trunk line, in the reverse direction.



  Relay 1421 releases due to the prolonged pull of relay 1423, it cuts the blocking circuit of relay 1420 which releases and removes the earth from wire 1451. When this happens and since the blocking wire L of cable C0-1 is an extension of wire 1451, relay 1CB in fig. 22 relax. Therefore, no other supervision signal is received on the body wire S of the cable c-1 In addition, removing the earth from the incoming control wire 1451 has the effect of preventing the relay from being pulled. 1427 whatever the relative positions of the lower springs of relays 1422 and 1410.



   At the end of the release signal, relay 1423 releases and completes removing the earth connection from blocking wire 1450, thereby relay 1417 releases and disconnects relay 1422 from body wire S ending in an LC line circuit -2 of fig. 33. The LO-2 line circuit can therefore return to the normal position and allow the primary interurban selector and the transceiver to be released.



   29, Total occupation in one level of a selector.



   If all connection circuits are occupied in

  <Desc / Clms Page number 70>

 the chosen level of the Rio de Janeiro switches during the flow of an incoming call on the TL-4 trunk line, the current flowing through the test lead of the established connection increases and decreases at the usual rate of 60 times per minute.



  The sending of the group occupancy supervision pulses is carried out as previously explained.



   30. Busy of the called line.



   When the called line is busy the effect is the same, i.e. pulses are transmitted on the test wire of the connection established, except that the rate is 120 per minute instead of 60, to allow the operator to distinguish between the occupation of a line and the occupation of a group of junctions.



   31 The distributor AL,
The functions of the distributor AL will now be described in more detail, FIG. 28.



   The relays 1705 and 1709 are associated, respectively, with five seekers, such as the finder F3 and when these relays are attracted the incoming starter wire 6 is extended to the finder F3 through the contacts of the relay 1705.



  When this finder is put into service, the relay 1705 is unblocked and released under the action of the relay 1701, it transfers the starting wire, which passes through the contacts of the relay 1706, to the finder which is associated with it. Likewise, relay 1706 is released and released when the searcher with which it is associated is put into service.



   When all seekers have been turned on and relay 1709 releases, the circuit of relay 1710 opens fully, relay 1711 draws to record the number of times that relay 1710 operates.



   When relay 1710 attracts it switches on the coil of relays 1705 to 1709 which attract at the first beat.

  <Desc / Clms Page number 71>

 



  The blocking contacts of relays 1705 to 1709 being closed, each of these relays, associated with a free finder, operates fully via the corresponding test wire, therefore relay 1710 attracts and relays which have no attracted only partially release.



   F. Call from Sao Paulo to Campos.



   It will be assumed that the interurban operator of Sao Paulo is called to establish a connection to a line in the Campos office through a junction taken from a group of interurban lines, the TL-5 line in fig, 1, 3 and 33 'being one of them.



   1, Commissioning and calling on the TL-4 trunk line.



   In this case, the operator in Sao Paulo sends the digits 4 and 6 (see fig. 2) which are necessary to extend the connection to the Rio de Janeiro office, then she puts her transmission key back in position. idle to allow the transmission of the automatic sending pulse of the inrush current to the operator serving the interurban table in Rio de Janeiro.



   When the K-6 transmission key has returned to the normal position, after sending the digits 4 and 6, the relays 1102 and 1101 pull so that the junction is no longer energized.



  The relay 521 then releases and causes the attraction of the relay 505. The relay 1126 attracts under the action of the momentary impulse to automatically send the inrush current, it closes the circuit of the relay 1127 to its lower interior contact. The relays 1127 to 1131 perform a cycle of operations to ensure the transmission, on the TL-4 trunk line, of a current pulse at 1000 periods, modulated at 60 periods.



   In the IR-4 pulse repeater, relay 1424 attracts, under the action of the pulse to send the inrush current,

  <Desc / Clms Page number 72>

 before relay 1423 attracts. When relay 1424 pulls, it closes the circuit of the lower winding of relay 1416 which attracts and blocks under the action of its two windings connected in series when relay 1424 releases.



   2. Commissioning of the line circuit of fig. 32.



   When relay 1423 attracts a signal pulse is transmitted via wire RD to relay 1901 which draws and closes its own blocking circuit, in series with relay 1902, via wire 1451 grounded. Relay 1902 does not draw until the initial pulse is completed.



   At the end of the signal, the relays 1424 and 1423 release.



  Relay 1423 ends the pulse sent to the RD wire, and the relay 1424 allows the relay 1416 to attract at the second time and open its blocking circuit, at the same time it transfers the RD wire of sending the 'inrush current pulse to relay 1415.



   3 Signaling to the called operator.



   In the line circuit of fig. 32, relay 1902 draws in series with relay 1901 at the end of the pulse to send the inrush current. The 1902 relay attracts to warn the operator by causing the 1907 lamp to light.



  Relay 1902 does not attract under these conditions because wire 1451 is not connected to earth, during the transmission of the release pulse, so as to open the blocking circuit of this relay.



   The pull of the 1902 relay also has the effect of transferring the S test lead from the repeater to the lead terminating in the LC-2 line circuit, fig. 33 and connect it to earth through contacts of relay 1905. Relay 2021 therefore releases and the incoming selector and associated recorder-transmitter are released if they have been connected to the line circuit.

  <Desc / Clms Page number 73>

 



   4. Line supervision.



   In the IR-4 repeater, relay 1422 draws into the circuit of the test lead because a ground is connected to this lead through relay 1902. A 1000 period, modulated current pulse is fed back over the TL trunk line. -4.



  Relay 1417 attracts while sending the supervision pulse and relay 1437 releases. Relay 1409 pulls immediately and relay 1410 pulls at the end of the supervisory pulse.



   In the event that the attendant has returned the conversation key K-3 to the rest position, the lamp 509 of the CC-1 cord circuit lights up under the action of the supervision pulse.



   It can be assumed that the operator serving the long distance position of FIG. 33, responds to the call, marked by the lighting of the 1907 lamp, by inserting the response plug AP of the 00-2 cord circuit into the J-l jack. When this occurs, the 1800 ohm top winding of the 1905 relay is fed through the plug body and jack barrel in series with the 2001 lamp, but the lamp does not light up at this time because the current flowing in this circuit is very low. The 1905 relay closes the circuit of the 1903 relay, this relay attracts to extinguish the 1907 lamp, at the same time it is blocked by means of the earth taken at the contacts of the 1902 relay.



   5. Response supervision.



   The 1905 relay also removes the earth placed on the test lead leading to the 1422 relay, this relay releases to cause a response supervision pulse to be sent on the TL-4 trunk line to give the op- failing caller a response supervision, by turning off the lamp, when she replaces her conversation key in

  <Desc / Clms Page number 74>

 rest position.



   The operator serving the long distance position of FIG. 33 activates her conversation key K-9 to make the 2002 relay attract and connect her headset telephone in the CC-2 cord circuit when she answers the call, thus resistor 2101, of 44,000 ohms, A middle tap, supplies sufficient current in the conversation wires to keep relay 1433 attracted after its local circuit has been closed to the lower contacts of relay 1409.



   6. Establishment of the connection to Campos.



   When she learns that the connection must be established to the Campos office, the operator inserts the CP call plug of the CC-2 cord circuit into the J-3 jack of a free TL-5 trunk line. , she activates the keys K-10 and K-15 to transmit the inrush current on the TL-5 interurban line and alert the operator of Campos. When the Campos operator answers the Rio operator returns the K-9 key to the rest position to release the 2002 relay and disconnect her equipment from the cord circuit. The Sao Paulo operator enters into direct conversation with the Campos operator who establishes communication to the requested line.



   Relay 1433 releases when the operator of fig. 30 returns its conversation key to the rest position, relay 1434 then removes bypass 1460 so that interurban line TL-4 can work in tandem with another trunk line.



   7. Callback of the operator from Rio de Janeiro.



   If the Sao Paulo operator wishes to call back the interurban operator in Rio de Janeiro, she momentarily activates her call key to transmit a current pulse at 1000 periods, modulated at 60 periods, on the TL interurban line. -4, which causes a momentary attraction of relay 1423.

  <Desc / Clms Page number 75>

 



  Relay 1415 then draws to prepare the circuit of relay 1414, which closes momentarily, when relay 1423 releases.



  An earth is then momentarily disconnected from the RR wire sending the pick-up current which momentarily removes the short circuit of the top winding of relay 1904 which draws into a circuit where it is connected in series with a 1000 ohm resistor. Relay 1904 is blocked by the action of its lower winding, while at its upper contacts it opens the circuit of its upper winding. Lamp 2001 lights up in series with the lower windings of relays 1904 and 1905, respectively, to give a boost signal.



   When the attendant responds, by activating her K-9 key to attract relay 2002, lamp 2001 is switched off and the associated body wire is transferred into the circuit comprising the 590 ohm resistor. This transfer has the effect of reducing the current in the body wire by a sufficient amount to allow the 1904 relay to release and open its blocking circuit, but the 1905 relay remains attracted by the action of its winding. higher than 1800 ohms.



   8. End and recall supervision.



   When the conversation is over, the operator in Rio de Janeiro receives end supervision from the Campos office. She cuts off the communication by removing the plug from the J-1 jack which has the effect of releasing the 1905 relay which causes the sending of the end signal to the operator of the Sao Paulo office.



   The Rio de Janeiro operator can make the Sao Paulo operator's lamp flicker by removing and reinserting the card in the event that she wishes to call the operator back from the original office.



   Or the operator in Rio de Janeiro can activate her call key to attract the call relay 1426

  <Desc / Clms Page number 76>

 which transmits a 60-period modulated current pulse on the trunk line to remind the operator of the home office.



   9. Release of organs.



   The operator at the Sao Paulo office may be the first to cut the line. When this occurs a sustained release pulse is transmitted over the TL-4 trunk line, from the Sao Paulo office, to the Rio de Janeiro office. When relay 1423 pulls at this moment, relay 1421 releases followed by relay 1420 which cuts the circuit of relay 1422 to prevent pulling of relay 2021 when the line circuit of fig. 32 returns to rest.



   Relay 1420 removes the earth connected to wire 1451 and relays 1901 and 1902 release followed by relay 1903.



  Earth is then placed at the barrel of jack J-1, at the contacts of relay 1902, through the lower 85 ohm winding of the 1905 relay, in parallel with the upper 1800 ohm winding of this relay, which increases the value of the current which circulates in the body of the plug and the barrel of the jack in a sufficient proportion to ignite the lamp 2001 of response supervision and give an end signal.



   When the attendant removes the AP response form from jack J-1, relay 1905 releases.



   G. Call from Rio de Janeiro to Sao Paulo.



   To explain how communications are established in the reverse direction on the interurban lines between Rio De Janeiro and Sao Paulo, we can assume that a call is received at the interurban table in fig. 33 and that it is intended for a subscriber in the Sao Paulo office.



   1. Commissioning of the TL-4 trunk line.



   We can assume that the operator finds the J-2 jack free and that she inserts the CP call card into it. When this happens, He-

  <Desc / Clms Page number 77>

 presents the relay 1435 of the IR-4 repeater attracts and closes the circuit of the relay 1436. At the upper group of its contacts, the relay 1436 disconnects the head and neck wires T and R, from the J-2 jack, from the trunk line TL -4 and transfers them, through code wires 2 and 4 of cable 1700, to the contacts of the researcher bench F-3, fig. 21, and the multiples of these contacts in the benches of other researchers. At the same time, pulse wires 1 and 3 of cable 1700 are connected to the portion of the talk wires associated with relay 1403 to prepare for transmission of the pulse.

   In addition, relay 1436 places, on cut-off wire 5 of cable 1700, a polarity marking the device as being free, this polarity is brought through the 400 ohm winding of relay 1405, normally shunted by the resistance of 200 ohms. Relay 1436 also applies a ground to wire 6 of cable 1700 through the contacts of relay 1407 which determines the length of the release pulse.



   2. Starting the F-3 finder.



   If we assume that the relays of the distributor AL, fig. 28, are in the position shown on the plan, it can be seen that the application of an earth to the starting wire 6 closes the circuit of the relay 1703. At the same time the relay 1701 attracts at the first time only, it places an earth at the start. junction point of the windings of relay 1702 and consequently on the brush 5 of the researcher F-3.



   When the relay 1703 attracts, it closes the circuit of the control electromagnet 1704 which cooperates with the relay 1703 to rotate the seeker brushes.



   When the finder brushes reach the pins assigned to the IR-4 repeater, the lower winding of relay 1702 is energized. When the relay 1702 attracts, it opens the circuit of the electromagnet and bypasses its

  <Desc / Clms Page number 78>

 upper winding to increase the effect of the earth connected to the cut-off brush 5. The relay 1702 also applies an earth to the blocking wire 1725, thus the relay 1701 at0 pulls all the way and opens the blocking circuit of the relay 1705 which releases and transfers the starter wire to the next seeker. With the 1705 relay blocking circuit off, this relay cannot re-attract to preselect seeker F-3 until the seeker has been released and relay 1701 has released.



   The 1701 relay also connects the RG group relay to the code 2 and 4 wires of the 1700 cable, it connects brushes 1 and 3, head and neck pulse, of the finder F-3 to the pulse contacts, normally closed, of relay 1838. Relay 1403 of the IR-4 repeater attracts and opens its contacts to prepare for sending the control pulses which are determined by the position taken by the recorder-transmitter of FIGS. 30 and 31
Repeater relay 1405 attracts Due to the pull of F-3 finder relay 1702, it closes the circuit of relay 1406. Relay 1406 attracts and closes the circuit of relay 1407.

   Relay 1407 disconnects the working contacts of the lower inner spring of relay 1423 and relay 1420 and connects them to the wire that controls relays 1409 to 1411; applies a ground to the blocking wire 1450 and it removes the ground from wire 6 of the cable 1700.



   3, Emission of the start-up pulse.



   Relay 1417 closes the circuit of relay 1427 which is blocked via wire 1450 and causes the pull of relays 1428 to 1430 as a result of sending, on trunk line TL-4, a pulse. current at 1000 periods, modulated at 60 periods.



   The relay 1413 attracts under the action of the relay 1429, it is blocked by the intermediary of the wire 1450 and opens the circuit

  <Desc / Clms Page number 79>

 initial energization of relay 1427 to prevent relays 1427 to 1431 from re-energizing. Relay 1413 also extends wire 1467 to resistor 1422 to cause the pull of the TU-4 device relay corresponding to TU-2 device relay 1201 and prepare for sending over the trunk line. pulses of unmodulated current.



   4. Switch on the modeling light.



   When the relays of the RG group, fig. 28, are connected to code wires 2 and 4 of cable 1700, the earth taken through relays B and A, is placed on lead wire 2 of cable 1700 and the earth, taken through relays D and C, is applied to wire 4. These wires now extend to the TC and RC wires at the head and neck of the calling side of the organs of the position, fig. 34, and the RG group relays are placed under the control of the keys of the 2100 call keypad. The earth connected to the RC neck wire from the operator position, through the windings of the code relays C and D, puts the 15000 ohm winding of relay 2103 energized. Relay 2103 attracts but code relays C and D of group RG do not attract.

   The relay 2103 causes the lamp 2104 to be turned on, to inform the attendant that she can start sending the desired number. If we assume that the call is for extension A, fig. 2, whose number is 84161, the operator sends this number preceded by the digit 2, which is necessary to extend the connection to a long distance office selector.



   5. Issue of number 284,161.



   When the key of number 2, of the 2100 keypad is activated, a strong negative impulse is transmitted on the neck wire through the lower contacts of the key, it is given by the negative pole of the current source at 24 volts, at through the 30 ohm protection resistor. In

  <Desc / Clms Page number 80>

 at the same time, a strong negative impulse is transmitted on the lead wire, it comes from the same source and passes through the upper contacts of the key of number 2. This agrees with the indications in the table given in fig. 35.



   In the RG relay group, relay B draws into the circuit of lead wire 2 of cable 1700, because the transmitted pulse is a strong pulse, but relay A does not attract because the transmitted pulse is a negative pulse . At the same time relay D attracts in the neck wire circuit because the received pulse is a strong pulse, but relay C does not attract because the received pulse is a negative pulse. Relays B and D close their own blocking circuits.



   The circuits of relays B and D of the digital recorder DS-1 of the RS-1 recorder-transmitter of FIG. 30 are therefore closed. When relays B and D attract, the contact placed at the top of the pyramid of contacts controlled by relays A and D is connected to the wire of number 2 in the group of wires of numbers 1 to 9.



   When the send key is returned to the rest position, relays B and D, of group RG, release, relay 1821 draws in the blocking circuit of this relay to disconnect wires A to D of the relays of the device. DS-1 for storing digits and transposing them to the identical relays on the DS-2 device to allow the second digit to be recorded by the second recording device.



   6. Starting the transmitter.



   Relay 1821 also places a ground on wire 1810 to turn on the switch made up of relays 1837 to 1839 and perform the retransmission of the stored digits.



   The 1822 relay attracts when the key is returned

  <Desc / Clms Page number 81>

 rest after sending the second digit, it transfers the control wires to the DS-3 digit logger and establishes a new ground connection for wire 1810.



   Likewise, the remaining digits are stored in devices DS-3 to DS-6 respectively.



     7. Switching off the modeling light.



   When relay 1826 draws at the end of the registration of the last digit, 1, it disconnects the earth of the RG group relays, in addition, it places an additional earth on wire 1810. When the relays A to D of the group are switched off, relay 2103 releases which switches off lamp 2104 and lets the operator know that all the digits have been recorded by the RS-2 recorder-transmitter.



   The calling operator can then return keys K-12 and K-9 to the rest position and wait for a signal giving online supervision.



   8. Retransmission of stored digits.



   When a ground is placed for the first time on wire 1810 the relays 1828 and 1829 successively attract to connect wire 1812 to wire 1822. Likewise relay 1837 draws and places additional earth on wire 1810, thereby cycling operation of the relays 1837 to 1839 is born. Relay 1837 attracts relay 1838 and the latter attracts relay 1839. Relay 1839 cuts the circuit of relay 1837 and allows it to release. When the relay 1837 releases it causes the release of the relay 1838; releasing relay 1839 releases relay 1839, relay 1839 again connects relay 1837 to the start wire to allow the cycle to be renewed.



   While relay 1838 is attracted the head and neck wires, 1 and 3 of cable 1700, are connected to each other to allow repeater relay 1403

  <Desc / Clms Page number 82>

 IR-4 pulses to release momentarily.



   Likewise whenever relay 1838 attracts, it closes the circuit of relay 1850 which attracts and blocks but no current flows through the blocking circuit as long as the excitation circuit remains closed. But when relay 1838 releases, relay 1851 pulls to connect the wire of digit 1 to the lower winding of relay 1840, sending the digit is done immediately in the case where it is precisely 1. In the example currently the first digit is 2 and the wire of digit 1 is not switched on.



   Relay 1851 also closes its blocking circuit which passes through its upper winding, it transfers the blocking circuit of relay 1850 from its lower winding to that of relay 1852.



   During the next cycle of operation of relays 1837 to 1839, another pulse is transmitted, to the upper contacts of relay 1838, to the line relay of the repeater to release this relay momentarily and to attract relay 1850 again. At this time, since relay 1851 is attracted, the blocking circuit of relay 1850 closes through relay 1852. As a result, relay 1852 attracts at the end of sending the second pulse. When relay 1852 pulls, it transfers the blocking circuit from relay 1850 to relay 1853. When this happens, relay 1850 releases again. The relay 1852 is blocked by the intermediary of its upper contacts in circuit and the wire 1811, at its lower contacts it puts / the wire of the number 2 which is energized.

   The circuit of the lower winding of relay 1840 is therefore closed. At its upper contacts, relay 1840 places a shunt on the upper contacts of relay 1838, thus preventing the transmission of another pulse when the relay 1858 is pulled.

  <Desc / Clms Page number 83>

 



  The pulse train constituting the number 2 is therefore terminated.



   Relay 1840 also blocks through the branching of the blocking wire and through the contacts of relay 1843. Relay 1840 also prepares the circuit through the lower winding of relay 1841 at the same time. connects a ground to wire 1723. This has the effect of attracting relay 1827 which locks up.



   In order to free the controller from the pulses, the relay 1840 disconnects the earth of the blocking wire 1811, thus all the relays which have drawn, in the group of relays 1851 to 1860, release, All these relays being released and the relay 1840 being blocked the blocking circuit of the relay 1850 is prepared, it will close at the moment of the next pull of the relay 1838. The relay 1841 attracts and is blocked when the relay 1838 releases at the next time; prepares the circuit passing through the lower winding of relay 1842 to attract the latter at the end of the time interval between sending two consecutive digits, it prepares a new circuit for starting the cycle of the relay. control chain and disconnects the earth from wire 1723 'and therefore from wire 1723.

   When this occurs, relay 1831 draws into a circuit including relay 1827. At its lower contacts, relay 1831 closes its own blocking circuit through its lower winding and the winding of relay 1812; it transfers the blocking circuit from relay 1827 to relay 1832, thereby relay 1827 releases; at its upper contacts it disconnects the earth of the blocking circuit of relay 1821 and of the contact placed at the top of the pyramid from the contacts of the DS-1 device for recording the number and transfers it to the contact placed at the top of the pyramid contacts of the DS-2 device. At the same time, the 1821 relay

  <Desc / Clms Page number 84>

 releases as well as relays B and D of the DS-1 device.



   With relays 1840 to 1841 pulled in and blocked and relays 1851 to 1860 released, the next time relay 1850 pulls under the action of relay 1838 it will block again in series with the lower winding of relay 1851 since wire 1811 has been connected to wire 1722 '. The relay 1851 therefore attracts at the time of the next release of the relay 1831 and prepares the circuit of the relay 1852. The following control relays attract successively under the action of successive attractions of the relay 1850 until the relay 1842 has attracted. When relay 1842 attracts depends on the position of the flying wire 1807. As shown in the plan, the flying wire 1807 connects terminal 1801, associated with relay 1842, to terminal 1804, connected to the upper winding of the relay of control 1854.

   Under these conditions when the fourth of the control relays (1854) attracts and locks, the circuit of the lower winding of relay 1842 closes through the flying wire 1807 and contacts of relay 1841 which is attracted, relay 1842 attracts to prepare for sending the pulses of the second stored digit. It should be noted that the flying wire 1807 can be connected to either of the terminals 1802 and 1803 if it is desired to obtain a smaller interval between the pulse trains and that it can be connected to either either of terminals 1805 and 1806 if a larger gap is required between pulse trains.



   When the 1842 relay attracts, it closes its blocking circuit through its upper winding, at the same time it prepares the attraction of the 1843 relay for when the 1850 relay will attract the next time. In addition, relay 1842 disconnects wire 1811 from wire 1722 'again, which causes the release of the control relays which have drawn in the group of relays 1851 to 1860.

   All relays

  <Desc / Clms Page number 85>

 control being released and relays 1840 to 1842 being pulled, on the next pull of relay 1850 the blocking circuit of relay 1850 closes through the lower winding of relay 1845. So when relay 1838 releases at the next time relay 1843 draws into the blocking circuit of relay 1850 and closes its own blocking circuit through its upper winding. The relay 1843 also cuts the circuit of its lower winding to allow the release of the relay 1850, at its upper internal contacts it cuts the blocking circuit of the relays 1840 to 1842 to allow them to release. When relays 1840 to 1842 release they disconnect wire 1722 'from wire 1724 and relay 1843 releases.

   The shunt placed on the send contacts (the upper contacts of relay 1838) is removed when relay 1840 releases.



   The relays 1840 to 1843 being released as well as all the relays 1851 to 1860, the transmitting device can re-transmit and control the pulses constituting the second stored digit of the requested number.



   In an identical manner the digits stored in the device DS-3 to DS-6 are retransmitted with a suitable spacing between the pulse trains constituting the digits.



   When relay 1836 draws at the end of transmission of the sixth and last digit stored, it blocks and opens the blocking circuit of relay 1826 associated with the sixth recording device. Relay 1826 releases and removes ground from wire 1810 to cut power to relays 1857 through 1839. Relay 1826 again applies ground to group RG relays so that they can be re-controlled by the set. keys for sending additional digits if the number to be sent contains more than

  <Desc / Clms Page number 86>

 digits than the six digits that the transceiver can register at one time.



   Relay 1828 releases when ground is removed from wire 1810, it opens the circuit of relay 1829. Relay 1829 releases after a short time to remove ground from wire 1812 and allow relays 1831 thru 1836 to release again. The relays 1821 to 1826 being released, the recorded part of the transmitter is in a position to receive other digits in the event that these are necessary.



   9. Repetition of selection pulses.



   The way in which the selection pulses transmitted to the line relay by the transceiver are repeated on the TL-4 trunk line will be explained below.



   The first time relay 1405 releases, the lower contact closes the circuit of relay 1428 which disconnects the receive wires 1462 from the TL-4 trunk line and at the same time removes the ground from wire 1465, to allow the release of the wire. TU-4 device transfer relay Corresponding to TU-2 device relay 1202, this causes the connection of a 1000 period polarity to the send wires 1461.



  At the same time, relay 1404 attracts and as it is delayed in operation, it remains attracted until the end of the sending of the pulse train. Relay 1404 closes the circuit of the top winding of relay 1428 to keep the relay continuously energized while the pulses are being sent.



   Each time relay 1403 releases it closes the circuit of relay 1429 which therefore momentarily draws in, it connects send wires 1461 to trunk line TL-4. In this way the pulses sent to the relay 1403 are repeated, in the form of current pulses at 1000 periods, on the trunk line TL-4.



   At the end of the transmission of the pulse train the

  <Desc / Clms Page number 87>

 relay 1403 remains attracted, relay 1429 returns to rest, relay 1404 releases after a short time and allows relay 1428 to release in turn.



   Each of the other pulse trains is repeated on the TL-4 trunk line in the same way.



     10. Establishment of communication in Sao Paulo.



   When the 1000-period current pulse, modulated at 60 periods, intended to put the components into service, is received on the TL-4 trunk line coming from Rio de Janeiro, the relay 1123 momentarily attracts as before to make the relay attract 1104 and to close the circuit of the relay 1120. The relay 1120 draws at first to close its blocking circuit passing through its two windings in series, this circuit becomes active when the relay 1123 releases.



  When the relay 1120 draws fully, it puts the wire 1151 to the ground, it disconnects the wire, controlled by the relay 1123, from the junction point of its windings and extends it to the relay 1116; it prepares the circuit of relay 1117; he places an earth on wire 1150; it disconnects terminal 1100-0 and its multiples of negative polarity indicating that the device is free and substitutes a protective earth for it; it places a ground on wire 0 of junction T-4, it connects relay 1122 to wire EC of junction T-4 and it closes the circuit of relay 1119.



   Relay 1119 closes the circuit of line supervision relay 1109 to prepare for the pull of relay 1109 when relay 1119 releases. Relay 1119 also closes the circuit of relay 1118. Relay 1118 disconnects the EC wire from the T junction -4 of the upper winding of relay 1122 and extends it to earth taken at wire 1150. In addition, relay 1118 connects the upper winding of relay 1119 to the terminals of the conversation wires of the junction. The winder-

  <Desc / Clms Page number 88>

 The upper ment of relay 1119 is energized in this circuit in series with the line relay (not shown) of the primary interurban selector TFS-3, fig. 8, which is identical to the TFS-1 long distance primary selector in fig. 7.



   The repeater is designed to receive the emitted pulses and to operate under their action in a manner identical to that which has been described previously. The relay 1124 beats according to the rhythm of the pulses and the relay 1104 remains attracted for the duration of the sending of a train. are the pulses / repeated to the next switch by the relay 1124, moreover this relay makes the relay 1116 attract at the first pulse, the relay 1116 causes the relay 1115 to attract.



   The TFS-3 interurban primary selector in fig. 8 therefore raises its brooms to the second level where offices are carried out the automatic search for a selector / free long distance.



   The TOS-1 interurban office selector operates under the action of the number 8, office code, to choose a junction leading to a thousand interurban selector in the called office; device operates under the control of the thousands digit, 4, of the requested number to extend the connection to a hundreds selector, interurban; the long-distance hundreds selector operates under the action of the hundreds digit 1 to extend the connection to a combined connector for local and long-distance service; the chosen connector operates under the action of the tens and units digits, 6 and 1, to extend the connection to the requested line, that is to say to station A in fig. 2.



   If it is assumed that the line of station A is free, at the end of the sending of the last digit of the number, the reversal of the direction of the current which takes place in the junction between offices,

  <Desc / Clms Page number 89>

 the moment the link is established with a free line, the TOS-1 selector relay 906 pulls in long distance offices, the relay 907 then attracts. At the same time, relay 905 attracts and closes the blocking circuit through the junction between offices, it puts the translator coil 951 in service and therefore cuts the power on the conversation wires to the TOS-1 selector of the switch. long distance offices. At the same time a ground is placed by relay 907 on the EC wire leading to the TOS-1 switch of long distance offices.



   He. Automatic sending of inrush current.



   When the relay 1104 releases at the end of sending the last digit, the relay 1119 alone remains attracted under the action of the current which runs through its upper winding. Therefore when the long distance office selector, TOS-1, fig, 10, operates when it receives line supervision from the called office and cuts the power to the conversation wires as we have seen. said above, relay 1119 releases and disconnects the ground from the control wire ending at relay 1109. Relay 1109 now pulls in and opens the local circuit of relay 1133 so that this relay can be controlled through the established connection. . Relay 1109 also opens the blocking circuit of relay 1116 which releases and opens the circuit of relay 1116, which momentarily closes the circuit of relay 1114.

   Relay 1114 momentarily pulls and places negative polarity on the positive talk wire terminating at the long distance office selector to attract relay 908 which sends the inrush current to the junction between offices to cause the subscriber to call. .



   12. Line supervision.



   Releasing relay 1119 also releases relay 1118 which closes the circuit of relay 1122.



  Relay 1122 therefore attracts to return a super-

  <Desc / Clms Page number 90>

 vision on the TL-4 trunk line. At the same time, the relay 1118 prepares the circuit of the relay 1117, it places the relay 1116 under the control of the relay 1123; it removes the earth from wire 1166 ending at relay 1204.



   After the attraction of relay 1122, the circuit of relay 1127 closes via wire 1151. The relays 1128, 1129 and 1130 therefore attract to cause the sending of a current pulse at 1000 periods, modulated at 60 periods, on the long distance line TL-4 ending at the calling office.



   At the same time as the pulse is sent over the trunk line, relay 1128 closes the circuit of relay 1117 which attracts and blocks.



   The relays 1107 and 1126 being released the circuit comprising the windings of the relay 1110 closes, this relay attracts when the relay 1130 releases, it transfers the circuit of the relay 1127 from the on contact of the relay 1122 to the rest contact of the latter.



   When relay 1117 attracts, relay 1104 is disconnected from the coil of relay 1131; the conversation threads are extended; additional earth is connected to wire C of junction T-4; the lower winding of relay 1122 is disconnected from relay 1114. Relay 1122 attracts under the action of its upper winding through the EC wire of junction T-4 before the lower winding of the relay is momentarily turned on energized in parallel with the winding of relay 1114.



   The line supervision pulse, current at 1000 periods, modulated at 60 periods, transmitted on the TL-4 trunk line is received in the TU-4 device, it attracts relay 1423 which closes the circuit of relay 1409 , this one attracts when this impulse is finished, it opens the local circuit of the relay 1433, established previously through

  <Desc / Clms Page number 91>

 resistors 1442 and 1445, to allow this relay to be controlled subsequently by the intermediary of the incoming conversation wires; it closes a new circuit for energizing relay 1405, it disconnects relay 1436 which releases; it disconnects relay 1403 from the closed bridge on the incoming conversation wires; at the same time it closes the conversation circuit and disconnects resistor 1443 of 600 ohms.



   13, Releasing the RS-1 transceiver.



   When relay 1436 releases when relay 1409 pulls, wire 5 of cable 1700 is cut and relay 1702 releases. When the relay 1702 releases it removes the earth from the ground wire 1722 to allow the release of the RS-1 recorder-transmitter of figs, 30 and 31.



   In the IR-4 repeater, with relay 1436 released and relay 1409 engaged, the head and neck wires from jack J-2 are extended to the windings of the trans- lator 1475.



   Relay 1409 by pulling places the lower 160 ohm winding of relay 1435 in parallel with the upper 1700 ohm winding, increasing the amount of current flowing through the barrel of jack J-2 and the body of the CP call sheet of a sufficient quantity to allow the lighting of the 2003 lamp.



   14. Response supervision.



   When the called subscriber answers and the current flowing through the trunk to the called office is cut, TOS-1 TOS-1 selector relay 907, fig. 10, releases and removes the supervisory ground of the incoming wire EC , therefore relay 1122 of the IR-2 repeater releases and closes the circuit of relay 1127 which attracts and causes the attraction of relays 1128 to 1130 when the response supervision pulse, with current at 1000 periods modulated, is transmitted sure

  <Desc / Clms Page number 92>

 line. The auxiliary relay 1130 closes the circuit of the relay 1111, through the contacts of the relays 1109 and 1110, at the end of this pulse. The relay 1112 therefore attracts to open the blocking circuit of the relays 1110 and 1111 which therefore release.



   In the Rio de Janeiro office, when the response supervision pulse is received, relay 1423 closes the circuit of the windings of relay 1410. Relay 1410 draws at the end of this pulse and disconnects the lower 100 ohm winding. of the relay 1435 of the shunt formed by the upper 1700 ohm winding, thereby the current flowing through the test lead of the connection is reduced by an amount sufficient for the supervisory lamp 2003 on the calling side of the CC-2 cord circuit is no longer receiving enough current to turn on. Therefore, the conversation key K-9 being released, the operator serving the position of FIG. 33 receives response supervision by switching off the lamp.



   15. End of communication supervision.



   When the called subscriber hangs up his receiver, relay 907 draws again and applies polarity to the associated incoming EC wire, relay 1122 of the IR-2 pulse repeater draws in again and closes the circuit of the relay 1127. An end supervision pulse, of current at 1000 periods modulated at 60 periods, is therefore sent on the TL-4 trunk line and, coinciding with the latter, a pulse is sent through contacts of relay 1109 to make attract relay 1110 again.



   In the Rio de Janeiro office, relay 1423 operates under the action of the end supervision impulse, it closes the circuit of relay 1411. Relay 1411 attracts relay 1412 which unlocks and releases relays 1411 and 1410 Relay 1410 again connects the lower winding of relay 1435 in shunt across the winding terminals.

  <Desc / Clms Page number 93>

 higher of this which establishes the power supply circuit of the 2003 lamp which, when lighting up, gives the end signal.



   16. Callback of the called subscriber.



   If the operator wishes to call back the called subscriber after he has hung up his receiver, she actuates the K-10 key (the K-9 key being in the working position) and then actuates the K-15 key to temporarily place a negative on the T lead wire that extends through the CP call plug head to the IR-4 pulse repeater lead wire.



  Relay 1426 then attracts and closes the circuit of relay 1427.



  A sending pulse of the inrush current, consisting of current at 1000 periods modulated at 60 periods, is transmitted on the TL-4 trunk line and relay 1123 attracts under the action of this pulse and closes the relay circuit. 1116.



  Relay 1114 attracts at the end of the pulse to apply a momentary negative to the positive talk wire of junction T-4, so as to attract relay 908 which transmits the inrush current on the wires of the junction. junction connecting. the offices to ring the called station again.



   17. Call back from the long distance operator.



   If the called subscriber wishes to attract the attention of the operator, he waves the fork of his set, this action causes the sending of a series of supervision pulses on the TL-4 line and the relays 1410 and 1411 attract and release intermittently by flickering the brightness of the supervisory lamp.



  * 18. Signaling of the occupation of a group.



   If at any given time all of the occupied junctions are found in a group, the intermittent application of polarity to the EC wire has the effect of causing relay 1122 to intermittently pull and release, causing a signal to be sent. succession of supervision pulses on the trunk line

  <Desc / Clms Page number 94>

 TL-4 to the IR-4 repeater. The first of these supervision pulses is received in the manner described for the reception of the on-line supervision pulse, the following pulse causes the brightness of the supervision lamp 2003 to flicker if the operator has handed over her key. conversation in rest position.



  The impulses are heard by the operator if her conversation key is left in the working position.



   19. Release.



   When the attendant cuts off the call, removing the CP call plug from the CC-2 cord circuit, fig. 33, of the J-2 jack of fig. 32, has the effect of opening the circuit of relay 1435, which releases and releases relay 1405. Relay 1405 opens the circuit of relay 1406 which releases, its weighted spring vibrates vigorously for about a second to delay the release of the relay 1407. When relay 1407 releases it removes the earth from ground wire 1450 and relays 1409 and 1413 release.



   After releasing relay 1405 and while relay 1407 remains engaged, the circuits of relays 1429 and 1428 close. Relay 1428 disconnects receive wires 1462 and removes ground from relay 1465, so the TU-4 device operates and applies a 1000 period, 60 period modulated current polarity to the 1461 transmit wires. until relay 1427 releases.



   In the Sao Paulo office, relay 1205 draws for a sufficient time to keep wire 1163 connected to ground. Relay 1123 then attracts for a sufficient time to allow relay 1121 to release. Relay 1121 releases and releases relay 1120 which also cuts off the earth connection at a point on ground wire 1150.



   When the sustained release pulse is over

  <Desc / Clms Page number 95>

 and the relay 1123 releases, the earth is completely removed from the ground wire 1150, and the relays 1109, 1110, 1113 and 1117 release. Relay 1121 attracts again when relay 1123 releases it again connects terminal C-1100 to relay 1105 making repeater IR-2 and trunk line
TL-4 available and allows them to be put back into service via terminals 1100 and multiples thereof.



   With relays 1117 and 1120 released, the guard ground is removed from wire C of the T-4 junction, terminating at the TFS-5 trunk primary selector. This selector therefore returns to idle and enables the next long distance office selector, TOS-1 of FIG. 9, to break free. Releasing the long distance office selector allows switches that have been put into service at the called office to be released in the usual way.



   The entire communication is now released.



   H, Call from Rio de Janeiro to Jundiahy.



   In order to explain a particular feature of the IR-2 supervisory / pulse repeater which is used only in the case of calls coming into the office in Sao Paulo and directed through this office to a long distance line. manual, we will assume that the operator serving the table in Rio de Janeiro receives a call intended for a subscriber of the office of Jundiahy that we reach from Rio de Janeiro through Sao Paulo.



   It is further assumed that the TL-1 trunk line of Figs, 1, 2 and 5 is turned on by the trunk line selector of Fig, 11, at terminals 460. The TLC-1 trunk circuit relay 409 attracts at the time of commissioning.



   1. Automatic line and answering supervision.



   Since there is no line relay connected to the terminals, wires from the T-2 junction, fig. 2 and 5, on which

  <Desc / Clms Page number 96>

 outgoing communications are established to interurban line TL-1, relay 1119 releases when this line is put into service and opens the circuit of relay 1118. Releasing relay 1119 under these conditions has the effect of opening the circuit. excitation of relay 1109 which attracts and opens the circuit of relay 1116 which releases.



   When relay 1116 releases, the circuit of relay 1115 opens and a circuit momentarily closes through contacts of relays 1115 and 1116 to attract relay 1114. Relay 1114 therefore momentarily attracts and applies a negative send pulse. of inrush current on the positive talk lead. At the same time the circuit of the lower coil of relay 1122 closes in parallel with that of the coil of relay 1114. Relay 1122 therefore attracts and closes the circuit of relay 1127. A line supervision pulse, of current at 1000 periods modulated at 60 periods, is therefore returned on line TL-4. Relay 1122 releases when this pulse is about to be sent, it prepares the circuit to send a second supervision pulse when relay 1110 draws.

   The circuit of relay 1110 closes at the lower contacts of relay 1130 and through contacts of relay 1109, so this relay attracts when relay 1130 releases and closes a new excitation circuit of relay 1127, through contacts of relay. relay 1122, and as soon as relay 1131 releases. A second response supervision pulse is therefore sent back to the Rio de Janeiro office to prevent the call supervision lamp from burning continuously throughout the duration of the communication because supervision is not received via the manual line called when the called subscriber answers.



   During the transmission of the response supervision pulse, relay 1111 attracts and causes relay 1112 to attract

  <Desc / Clms Page number 97>

 as described previously.



   When Jundiahy's operator answers, the two operators can enter a conversation and Jundiahy's operator can establish the connection to the requested line.



   2. Call back from the long distance operator at the home office.



   When the communication is established, if the operator of Jundiahy wishes to call back the operator of Rio de Janeiro, she can do so by sending inrush current on the inter-urban line TL-1 Each time a current pulse d the call is sent relay 407 attracts and releases the relay
406 which closes the circuit of the relay 405. The relay 409 being attracted, the blocking circuit of the relay 408 closes by means of its lower winding and through the wire.
EC of the connection established at the Sao Paulo office. This blocking circuit consists of the 800 ohm winding of relay 1122 of the IR-2 repeater. Relay 1122 therefore attracts whenever relay 408 attracts, but the latter does not get stuck in the blocking circuit due to the relatively high resistance of the upper winding of relay 1122.

   Thus, when the inrush current pulse ceases, relay 408 releases and opens the local circuit of relay 1122, which releases. Each time relay 1122 attracts it closes the circuit of relay 1127 through contacts of relay 1110, so that a supervisory pulse is sent over the trunk line. At the same time, relay 1110 attracts to transpose the circuit of relay 1127 so that it includes the normally closed contacts of relay 1122.



   In this way, each time relay 1122 releases at the end of an inrush current pulse, it closes the circuit of relay 1127, which causes an additional supervision pulse to be sent on the interurban line. , current at 1000 periods modulated at 60 periods.

  <Desc / Clms Page number 98>

 



   In the Rio de Janeiro office whenever a supervisory pulse is received, the resulting pull of relay 1423 has the effect of attracting relay 1411 which in turn pulls relay 1412 and releases relays 1410 and 1411. Therefore, whenever a supervisory pulse is received because relay 1122 has released, relay 1410 draws again. Each time relay 1410 releases it closes the circuit placing the 100 ohm winding of relay 1435 across the upper high resistance winding of that relay, causing the 2003 supervisory lamp to light on the calling side. in the CC-2 cord circuit. This lamp goes out when relay 1410 attracts again under the action of the supervision pulse indicating the end of the inrush current pulse.

   In this way, the 2003 lamp, supervising the call side, lights up momentarily each time the attendant at Jundiahy's office activates her call key, so this lamp can be made to flicker if you press in. - terminate the call key in Jundiahy's office to attract the attention of the operator in Rio de Janeiro.



   3, Call back from the long distance operator at the arrival office.



   The Rio de Janeiro operator can call back the Jundiahy operator at any time by activating her call key to send a pulse in the opposite direction on the TL-4 trunk line and momentarily attract the caller. Relay 1104 of the IR-2 repeater and start inrush current on the TL-1 trunk line terminating at Jundiahy's office.



   4, Release.



   At the end of the conversation when the interurban operator in the position of fig. 33 and 34 cut the TCC-2 cord circuit, the IR-4 repeater is released as described previously, it transmits a sustained release pulse to the IR-2 repeater, under the action of the repeater. releases as the primary selector does

  <Desc / Clms Page number 99>

 long distance TFS-3 in fig. 8. As a result of releasing the TFS-3 primary trunk selector, the TLS-1 trunk selector of fig, 1 returns to the normal position and releases the TLC-1 trunk circuit, fig. 5.



   I. Call from Rio de Janeiro to Campinas.



   To explain certain characteristics of the devices, which come into play only when a communication is established, through the office in Sao Paulo, from one automatic interurban line to another, it will be assumed that a call is made. received at the Rio de Janéiro table, fig. 33 and 34, to a subscriber of the Campinas office, fig, 1.



   When the operator in the Rio de Janeiro office inserts the CP call plug of the CO-2 cord circuit into the J-2 jack, fig. 32, the IR-4 repeater is put into service, the consequences / are explained below.



   1. Transmission of route figures.



   Since the communication must be established through the Sao Paulo office to a line in the Campinas office, the digit to be sent exceeds the maximum of digits (6) that can be recorded at once in the RS-1 transmitter recorder. . In this case the operator was instructed to record only part of the digits, for example, the three route digits, and to wait until they have been retransmitted before transmitting other figures.



   When the attendant transmits the first route digit using the appropriate key on her 2100 keypad, the group RG relays, fig. 23, operate as described previously, to have this number recorded by the relays of the DS-1 device, then the input relay 1821 of the distributor attracts to disconnect the DS-1 device and replace it with the DS- device. 2. The second route digit is therefore recorded in the DS-2 device and the third in the DS-3 recording device. The

  <Desc / Clms Page number 100>

 lamp 2104 will remain on after all three digits have been stored until they have been retransmitted.



   When the earth is removed from wire 1810, relay 1828 releases and opens the circuit of relay 1829. Therefore, earth is disconnected from relays C and D of group RG for the time necessary for relay 1829 to release. At this moment the relay 2103 releases and turns off the modeling lamp 2104.



   A moment later, relay 1829 releases and disconnects wire 1812 from wire 1722 allowing relays 1831 to 1833 to release to prepare for retransmission of additional digits that must be stored in devices DS-1 to DS. -3. At the same time, relay 1829 again extends the earth, taken at its upper contacts, to relays C and D of group RG, so relay 2103 attracts again and lights modeling lamp 2104.



   2, Transmission of the subscriber number.



   When this lamp comes on, the attendant sends all five digits constituting the number of the subscriber called from the Campinas office, the digits being received in the DS-1 to DS-5 registers. The transceiver operates as explained above to retransmit these five digits, then it remains connected to the LR-4 repeater through the F-3 finder until the line supervision signal is received from the called office.



   In the Sao Paulo office, the call flows through the TFS-3 primary interurban selector in fig. 8, the TLS-2 trunk line selector in fig. 9, and the TL-2 interurban line leading to the Campinas office and to which is added the IR-1 repeater of fig. 2, same as IR-2 pulse repeater.



   The IR-1 pulse repeater is ready to operate in the same way as the IR-2 repeater.

  <Desc / Clms Page number 101>

 



   Relay 1118 remains attracted through relay 1119 until the loop is opened. With relay 1118 attracted, the EC wire from junction T-4 (terminating at the incoming TFS-3 primary long distance selector switch in Fig. 8) extends, through the lower 250 ohm winding of relay 1108, to 1150 wire grounded. When the IR-1 pulse repeater in fig. 2 is put to work, it transmits a commissioning pulse to the remote office, meanwhile a relay attracts in this office, it corresponds to relay 1130 of the IR-2 pulse repeater.



  This relay places a negative on the EC wire entering this office, and corresponding to the EC wire entering the IR-2 repeater through the 1100 EC pin and multiples thereof. This negative is fed through the upper winding of the IR-1 repeater "long-to-long" relay corresponding to relay 1108 of the IR-2 pulse repeater. As a result, these two relays attract in series.



   When relay 1108 attracts, it disconnects wire 1150 from relay contact 1116 to release relay 1115; he cuts the wire 1136; it transfers the upper terminal of the upper winding of relay 1109 to earth and the relay immediately draws. Pulling relay 1109 has the effect of disconnecting leakage resistor 1143 and the line relay from the talk wire terminals. Relay 1109 also opens the blocking circuit of relay 1116 which releases, but without any effect because relay 1115 has already released. Relay 1109 also opens the local circuit of relay 1133 previously established through resistors 1142 and 1145, allowing that relay to release and pull.



   Relay 1108 closes, via wire 1150, the circuit of the lower windings of relays 1117 and 1119 in series. Relay 1117 therefore attracts and relay 1119

  <Desc / Clms Page number 102>

 who is attracted remains blocked locally. Relay 1117, at its two uppermost contacts, extends the connection, at the same time it removes the top winding of relay 1119 which formed a bridge across the conversation wires.



   In the outgoing repeater IR-1 of fig. 2, the pulling of the 'long-distance to long-distance' freight relay of this repeater, corresponding to relay 1108, has the effect of causing the attraction of the relay which is attached to it and corresponds to relay 1109. In the IR repeater -1 the line relay is therefore removed from the bridge placed at the terminals of the incoming conversation wires; the connection is extended to the wires coming out of the trunk line through the translator coil corresponding to the translator coil 1175; and the relay of disconnection of the blocking bridge attracts, in the repeater IR-1, to remove the bridge placed at the terminals of the TL-2 trunk line.



   The relay 1108 being drawn into the pulse repeater IR-2, and the corresponding relay into the repeater IR-1 of fig. 2 also being attracted, the two repeaters are no longer able to repeat other selection and / supervision pulses. The repeater at the far end of the TL-2 trunk line, in the Campinas office, is controlled directly by the IR-4 pulse repeater. All selection pulses transmitted by the IR-4 repeater pass through the TL-4 and TL-2 trunk lines in series, they are received and processed in the Campinas office pulse repeater as explained previously for the IR-2 repeater.



   When the connection has been established to the called line of the Sao Paulo office, following the transmission of the remaining trains of selection pulses, the line supervision pulse returned by the repeater in the Campinas office passes through the two interurban lines in series and has for

  <Desc / Clms Page number 103>

 effect of attracting relay 1409 in the IR-4 pulse repeater.



   The following operations are carried out as explained previously.



   4. Release,
When the attendant cuts the connection and consequently causes the sending of a prolonged release pulse by the IR-4 repeater, the IR-2 and IR-1 repeaters in the Sao Paulo office and the incoming repeater in the Campinas office operate, under the effect of this pulse, to release the connection in a manner identical to that described for the IR-2 repeater, in the case of an incoming call from Rio de Janeiro to a line from the Sao Paulo office.



  The "inteurbr ain to trunk" relays release following the release of relay 1118 which opens the circuit connecting these two relays in series.



   The conversation wire circuit remains however established between the calling office in Rio de Janeiro and the called office in Campinas for the duration of the sending of the release impulse because the relay 1117 remains attracted, thus maintaining connection made through the conversation wires and maintaining a ground on wire C of the T-4 junction after relay 1120 has released.



   When sending of the release pulse is complete and relay 1123 releases, relay 1121 draws again and ground is disconnected from blocking wire 1150.



  At this time, the relays 1109 and 1117 which were blocked release, which puts the repeater IR-2 back in the rest position.



  Relay 1117 removes the earth from wire C of the T-4 junction which allows the selectors of fig. 7 and 8 to return to the normal position and release the interurban line leading to the Campinas office.

  <Desc / Clms Page number 104>

 



   J. Call from Campinas to Rio de Janeiro.



   In order to complete the description of the characteristics of the system relating to connections in which two automatic trunk lines are connected to each other in the case of transit operation, the essential operations which are carried out during the establishment of the telephone will be explained below. 'a communication from the Campinas office to a line at the Rio de Janeiro office.



   It can be assumed that the connection is established from the Campinas interurban office to the TL-2 interurban line in Figs. 1 and 2 in the same way that connections are made from the Sao Paulo trunk office to an outgoing trunk line.



   When the TL-2 trunk line of fig. 1 and 2 is put into service at the Campinas office the IR-1 repeater is ready for operation and the connection is established through the TFS-3 primary trunk selector, the TLS-2 trunk selector and the TL-4 trunk line . Repeater IR-2 relay 1103 attracts as well as relays 1105 to 1107.



  As a result of the operation of relay 1107, the circuit of relay 1127 closes and this relay sends a momentary, energizing pulse on trunk line TL-4. Relay 1108 draws in the circuit that connects it in series with the lower coil of the corresponding "long distance to long distance" relay in the IR-1 pulse repeater of fig.2.



  The IR-1 pulse repeater is therefore suitable for working "long distance to long distance" as explained previously.



   At this time, when relay 1108 attracts and since wire 1151 is not grounded, the series lower windings circuit of relays 1117 and 1119 is not closed. Relay 1108 connects its top winding to

  <Desc / Clms Page number 105>

 incoming wire EC and is blocked, it disconnects the upper contacts of relay 1110 and attracts relay 1109 by means of its internal upper spring. The relay 1109 disconnects the leakage resistor 1143 from the bridge placed at the terminals of the left windings of the translator coil 1175 and extends the conversation wires, entering, to the trunk line via the translator coil, at the same time. time it disconnects the relays 1102 and 1103 of the bridge placed at the terminals of the incoming conversation wires.

   Relay 1109 also opens the circuit of relay 1133 to allow relay 1134 to pull through wire 1150 to cut the circuit of bridge 1160.



   The selection pulses received from the repeater leaving the Campinas office pass through terminals 1100 ,.



  positive and negative, and across the TL-4 trunk line without having any effect on the TU-2 device or the IR-2 repeater. The incoming signaling relay 1205 of the TU-2 device becomes active when supervision pulses are received from the called office, Rio de Janeiro, as well as when pulses to send the inrush current must be forwarded to the Rio de Janeiro office.



   The organs of the Rio de Janeiro office operate during this communication as explained in the case of a call from Sao Paulo to Rio de Janeiro.



   When the conversation is over and the call has to be cut off, the extended release pulse is transmitted by the repeater leaving the Campinas office, this pulse is received by the IR-1, IR-2 and IR-2 pulse repeaters. IR-4.



   In the IR-1 pulse repeater, this pulse has the same effect as that described in the case of a call, in the opposite direction, through the im- repeater.

  <Desc / Clms Page number 106>

 IR-2 pulses. In the IR-2 pulse repeater, the prolonged pull of relay 1123 causes relay 1121 to release. Since relay 1120 is released, the only result at this time is the opening of the first circuit d. Power to relay 1105 passing through incoming wire C and connected to the earth brought by the trunk line selector. Relay 1105 therefore releases and releases relays 1106 and 1107, the latter with a certain delay. During the delay time of relay 1107 the circuits of relays 1128 and 1129 close, they attract to transmit a prolonged pulse on the TL-4 trunk line.



   Relay 1113 attracts under the action of relay 1129, it locks to keep relay 1105 disconnected from terminal 1100-C until the repeater has completely returned to idle.



   When relay 1128 attracts, it opens the talk wire circuit to isolate translator coil 1175 and receive wires 1162 from the TL-4 trunk line, which ends sending the release current on the TL- trunk line. 4. At the same time, the relay 1128 causes the sending on the trunk line TL-4 of a signal with 1000 periods, modulated at 60 periods. In this way when the sending of the release current by the originating office stops, the release current is sent by the repeater IR-2, the / continuity between the two actions being so weak that the relay of release. incoming signaling and signal repeater relays from the Rio de Janeiro office do not have time to release.



   When the release pulse is about to be sent from the IR-2 repeater, the release pulse sent from the Campinas office is complete and the IR-1 repeater in fig. 2 reverts to idle and allows the associated TFS-2 primary trunk selector and the TLS-2 trunk selector to revert to idle as well.

  <Desc / Clms Page number 107>

 



   Relay 1107 remains engaged and the release pulse continues to be transmitted until relay 1107 releases and opens the circuits of relays 1128 and 1129. Relay 1107 also removes ground from blocking wire 1150 which completes the return to normal position of the repeater by allowing the release of blocked relays.



   The devices at the Rio de Janeiro office come back to rest in the usual way when the release pulse is sent.



   K. Automatic release of the IR-2 repeater after a determined time.



   Arrangements have been made to release the IR-2 repeater if a false arming pulse is received by the device. In this occurrence, relay 1123 can attract, as in the case where it receives a commissioning pulse, it causes relay 1120 to attract which causes the relays 1119 and 1118 to be drawn.



   The attraction of relay 1118, whether it is a genuine call or a false call, connects wire 1176 to relay 1132. Wire 1176 is momentarily connected to ground intermittently, after a few seconds, to pull relay 1132 at the end of the pulse. If, however, select pulses are received before the pull of relay 1132 the circuit of wire 1176 is opened as a result of the pull of relay 1116 and relay 1132 cannot pull. If relay 1132 has already drawn, and select pulses are received shortly thereafter, relay 1132 releases due to the opening of its blocking circuit by relays 1119 and 1109.



   If no select pulse is received relay 1132 pulls when the periodic pulse ceases and locks up through ground wire 1150. So the next time wire 1176 is connected to ground relay 1123 draws for a time long enough to

  <Desc / Clms Page number 108>

 allow the release of the relay 1121 which releases the relay 1120. The relay 1104 attracts incidentally following the closing of the lower contacts of the relay 1123, it closes the local blocking circuit of the relay 1119 by means of its lower winding, this circuit opens when relay 1120 releases. The relay 1119 remains attracted by the action of its upper winding in the control circuit of the loop.



   With relay 1120 released, ground is disconnected from blocking wire 1150 when relay 1123 releases at the end of the periodic pulse. Relays 1118 and 1132 are therefore slack. Relay 1118 disconnects wire 1172 from relay 1132 and opens the loop. The relay 1119 therefore releases and the incoming selector can be released.



   Note that periodic pulse wire 1176 is cut by "long distance to long distance" relay 1108 to avoid any initial pull of relay 1132 when an incoming long distance call is extended to a second automatic long distance line.



   The release of the IR-4 repeater after a determined time interval is carried out in a manner identical to that described for the IR-2 repeater.



   L Blocking of a defective automatic trunk line.



   Relay 1125 was provided in the IR-2 repeater to prevent the TL-4 automatic trunk line from being put into service in Sao Paulo when it became faulty.



  When this relay attracts it is blocked via wire 1147 terminating at the test panel; it transfers the C-1100 terminal of the coil of relay 1105 to earth to make the repeater IR-2 inaccessible and to attract relay 1136; it disconnects the earth of the inner lower spring of relay 1123 to prevent the attraction of relay 1120 if the line is

  <Desc / Clms Page number 109>

   commissioning at the remote office; connects the common wires bringing the guard tone to the TL-4 trunk line, on the office side, to send a warning tone on the line and notify the operator in Rio de Janeiro of. that the trunk line is faulty in the event that it is put into service at the other end.



   Relay 1125 can be powered from the test panel through wire 1146 when desired; can be blocked in the working position of the test panel by the intermediary of this wire after the blocking circuit of this relay has been cut on wire 1147, to extinguish the signal lamp which was supplied by that -this.



   Similar arrangements are also made at the IR-4 repeater.



   M. Testing automatic trunk lines.



   Provision has been made for the means enabling an operator from the Sao Paulo testing service to extend the connection to an interurban line leading to Rio de Janeiro, in order to test the line and its associated units in Rio de Janeiro.
To carry out the tests, the operator, after having put the trunk line into service, sends the number 9, the effects of these operations are described below.



   The IR-2 repeater transmits a wake-up pulse on the TL-4 trunk line to the IR-4 repeater. This repeater operates as described above and puts the CR code transmitter into service.



   In addition, the LC-2 line circuit of fig. 33, activates a primary interurban selector and a recorder-transmitter to allow the connection to be extended.



   The operator of the position of FIG. 6 then emits the number 9

  <Desc / Clms Page number 110>

 
The operator can then return keys K-6 and K-3 to the rest position, and wait for the supervision signal indicating that the organs of the Rio de Janeiro office are ready to operate properly.



   When the K-6 key is returned to the rest position the loop is unbalanced to allow relay 1102 to attract relay 1101 so that the line is no longer live and to extend the conversation wires. The relay 1126 then attracts momentarily, under the action of an automatic operation of the relays of the trunk table, to transmit a sending pulse of the inrush current on the trunk line and register it in the relay 1415.



   In the CR code transmitter reception of the digit 9 has the effect of attracting the recording relays A and C of the device DS-1. The operation of the code transmitter is identical to that which has been described except that since only one digit has been transmitted, no pulses are transmitted to the recorder-transmitter and, moreover, relay 1602 releases when the amplitude of the vibration of the spring of the relay 1601 is sufficiently reduced. This causes the cut of the pulse wire P and the release of the CR code transmitter. When the pulse wire is opened in the code transmitter the upper coil of relay 1419 is no longer energized, the relay releases and closes the circuit of the lower coil of relay 1422.



   When relay 1422 attracts, it closes the circuit of relay 1427. Relays 1427 to 1431 then complete a cycle of operations as described previously, during this time a line supervision pulse is returned through the line. interurban TL-4 to the Sao Paulo office. It is the reception of this supervision pulse at the test table that indicates to the operator that the TL-4 trunk line

  <Desc / Clms Page number 111>

 and the bodies associated with it in the Rio de Janeiro office are in a working position.



   Relay 1417 attracts under the action of relay 1428 during the transmission of the supervision pulse. Relay 1417 opens the blocking circuit of relay 1437, in addition it closes its own blocking circuit. When relay 1437 releases, it opens the local circuit of the lower winding of relay 1422 which remains off until the repeater is released. Relay 1422 therefore releases.



   With relay 1410 drawn another circuit now closes to energize relay 1427 and a response supervision pulse is returned to the test table.



  The relays 1411 and 1410 release as a result of the sending of the response supervision pulse, as a result the circuit of the relay 1427 remains open after this sending. When the line supervision pulse is received from the IR-2 repeater, relay 1109 draws and places a ground on the incoming EC wire to turn on the call supervision lamp at the table in fig. 5. This lamp goes out when relay 1110 attracts, under the action of the response supervision pulse, to remove the earth connected to the EC wire.



   When the operator of the tests service cuts the connection, the components put to work are released in the manner described above.



   0. RS-1 recorder-transmitter test.



   The arrangements for performing the RS-1 Recorder-Transmitter test, primarily for checking the frequency and pulse ratio, will be described below.



  When it is desired to perform the recorder-transmitter test, plug 1728 is inserted into jack 1727 to close the circuit of the upper coil of relay 1712 in series with test lamp 1729. Relay 1712 attracts. enough

  <Desc / Clms Page number 112>

 to close its blocking circuit by means of its two windings connected in series, it therefore draws fully and activates all its springs.

   The guard wire 1722 'is transferred from the guard wire 1722 to the ground; wire 1730 is cut to release relay 1705 and thereby keep the recorder-transmitter; wire 1723 'is disconnected from wire 1723 to prevent unnecessary operation of the relays; upper contacts of relay 1840 are made inactive to ensure continuous transmission of pulses through the contacts of jack 1726; a ground is placed on the 1810 starter wire to put the 1837 thru 1839 starter relays into service. Pulses are then transmitted from the upper contacts of relay 1838 through jack 1736 to an indicator device marking the relationship between the opening and closing times.



   Relays 1851 to 1860 are controlled by relay 1838 and under the action of relay 1850, as previously described, to control the first ten attractions of relay 1838, relay 1840 is then energized via the wire of guard 1722 'grounded so that it blocks through the contacts of relay 1843. Relays 1851 to 1860 release when relay 1840 attracts, then relay 1841 attracts to send pulses intended to attract relays 1851 to 1854 to control the spacing between digits as discussed previously.



   The 1842 relay then draws into a branch of the 1854 relay circuit to release the relays of the 1851 to 1860 group that would have attracted and to prepare the 1843 relay circuit.



   The relay 1843 then attracts under the action of the next pulse given by the relay 1838, it follows that the relays 1840 to 1843 release. The relays 1851 to 1860 being released at this time, the relays 1851 to 1860 and 1840 to 1843

  <Desc / Clms Page number 113>

 start again for a new operating cycle, the cycle repeating as long as the plug remains inserted in the jack 1727.



   In order to provide a safe means of obtaining the operating frequency of relay 1838 the wire 1724 is extended, through the contacts of the attracted relay 1712, to the lamp 1729. Therefore, when the relay 1840 attracts, the lamp turns on and remains on until relay 1843 attracts to release relays 1840 to 1842. This lamp turns on once for each complete operating cycle of relays 1851 to 1860 and 1840 to 1843. In observing the time required to obtain a determined number of flickers of the brightness of the lamp 1479 one can very simply and accurately determine the frequency of the pulses given by the relay 1838.



   When the 1728 plug is removed from the 1727 jack, the 1712 relay releases and allows the release of the recorder-transmitter.



   It can be seen that there is no problem in inserting the 1728 plug into the 1727 jack when the recorder-transmitter is in use, because at this moment the earth placed on the wire 1810 is short-circuiting the winding of the cable. test relay 1712, and cause lamp 1729 to glow steadily to give a busy signal.


    

Claims (1)

CLAIMS. ---------------------------- 1. A telephone system using alternating current signals to establish a connection , wherein, all supervisory signals take the form of one or more modulated alternating current pulse trains, the number of pulses of the train or trains or the spacing between the trains or one and the the other being different for the different signals. 2. A telephony system using alternating current signals for establishing a connection, in which., All supervisory signals take the form of one or more modulated alternating current pulse trains, and the characteristics of the trains with respect to the number of pulses of each train and the spacing of the trains are different for different signals. 3. A telephone system using alternating current signals to establish a connection under operator control, in which all signals take the form of modulated alternating current, those given during the correct establishment of a connection having the same characteristics and those given when establishment of the connection is not possible having characteristics different from those of the first signals and being different from each other depending on the point or connection is made impossible. 4. A telephony system using AC signals to establish a connection, in which the supervisory signals take the form of a modulated AC pulse train which is interrupted at different rates. in order to differentiate the signals from each other. 5. A telephone system using alternating current signals to establish a connection under the control of an operator in which supervisory signals take AT <Desc / Clms Page number 115> in the form of a modulated alternating current pulse train that is interrupted at different rates to give the operator distinct audible or visual signals. 6. A telephone system for establishing long distance communications under the control of an operator, in which the connection is extended to the long distance line by impulses sent by the operator, a signal then being transmitted automatically. on the trunk line to cause the addition to the trunk line of a pre-selected code transmitter, which allows the code transmitter to receive the impulses subsequently sent by the operator and to subsequently control the establishment of the connection in accordance with the recorded digits. 7. A telephone system for establishing long distance communications under the control of an operator, in which when long distance communication is to be established a long distance line is put into service, a recorder-transmitter is attached to the long distance line chosen for record the digits of the desired number and retransmit them on the trunk line, the end of the connection establishment causing the automatic forwarding of a signal on the trunk line to release the recorder-transmitter and make it available. - available for another call. 8. To be used in a telephony system, a recorder-transmitter controlled from an operator position and having the possibility of recording a given number of digits, in which the subscriber number comprising a certain number of digits in addition to the given number can be recorded because provision has been made for the recorder to be used a second time after the initially transmitted digits have been retransmitted, a signal being sent to the operator at the end of the retransmission to <Desc / Clms Page number 116> indicate that the remaining digits can be saved. 9. A telephony system as claimed in claim 1 or 2 wherein the supervisory signal which is transmitted to release the connection comprises pulses of alternating current modulated in a number different from that employed for the line supervisory, response and signal signals. the end. 10. A telephony system as claimed in claim 9 in which the currents induced in the conversation circuit when the called subscriber shakes his fork cannot be confused with the transmission of a release signal because it is the signal. talk circuit itself which is cut off when the release signal is sent. He. A telephone system as claimed in claim 1 to or 2 in which / upon completion of the sending of the pulses, a signal is sent automatically over the trunk line to cause the inrush current to be sent to the called subscriber. when the connection is established. 12. A telephony system as claimed in claim 11 in which the signal is stored at the incoming end of the trunk line until the connection has been established. A telephony system as claimed in claim 11 or 12 in which the signal has the same characteristics as the line supervision, answer and end signals. 14. A telephone system as claimed in claim 3 or 5 in which the operator at the home office can call back the operator located at the other end of the trunk line by activating a call key to call back. cause the sending of a signal having the same characteristics as the usual call signal, the time during which the key is actuated having no influence on the result to be obtained. 15. A telephone system as claimed in claim 3 <Desc / Clms Page number 117> or 5 in which when a connection is established by means of a long distance line to an operator position, the latter can call back the operator from the originating office by activating a call key, which causes sending two signals on the trunk line each time the key is operated, so as to flicker the brightness of a supervisory lamp from the operator position of the home office. 16. A telephone system as claimed in claim 3, 4 or 5 in which the signals transmitted when all the junctions are busy and when the called line is busy are interrupted at different rates. 17. A telephony system as claimed in claim 3 or 5 in which the operator of the home office puts a trunk line into service through a train of automatic switches in which pulses are transmitted by the line. operator to a repeater, assistant to the interurban line, through a balanced loop circuit, this circuit is unbalanced at the operator position at the end of sending pulses to cause the operation of a differential relay in the repeater and open the control loop. 18. A telephone system as claimed in claim 1, 2, 3, 4 or 5 and comprising repeaters of current at voice frequencies in which the hissing of the repeater is prevented by the addition of a leakage circuit at the incoming end of the trunk line, this circuit is disconnected when the communication is established. 19. A telephony system as claimed in claim 18 wherein the leak circuit is automatically disconnected when the line supervision signal is received, at the incoming end of the trunk line. 20. A telephone system as claimed in claim 1, 2, 3, 4 or 5 and comprising current-to-frequency repeaters <Desc / Clms Page number 118> voice in which an attenuation circuit is normally provided in the trunk line, it remains attached to it if it is connected to a local line, but it is switched off if the trunk line is connected to another trunk line. 21. A telephone system as claimed in claim 1, 2, 3 4, or 5 in which the translation of the signal currents into switch control pulses and supervisory pulses is carried out by repeaters installed at each end of the trunk line, the repeaters intermediaries inserted in the connection being rendered unfit to exercise their translator functions. 22. A telephone system as claimed in claim 1, 2, 3, 4 or 5 in which the translation of the signal currents into switch control pulses and supervisory pulses is carried out by repeaters installed at each end of the trunk line, if the trunk line leads to a manual office, the line supervision and response signals are returned automatically by the repeater located at the end of the interurban line where the manual office is located. 237 A telephony system as claimed in claim 6 in which if all code transmitters are in use a busy signaling device is preselected and put into service when a call occurs on the trunk line it transmits a busy signal. characteristic occupancy towards the operator through the trunk line. 24. A recorder-transmitter as claimed in claim 7 or 8 wherein the recorder is provided with a group of control relays which serve to terminate the sending of pulses from the recorder when the desired number of pulses have been completed. transmitted and which is used to control the pause time between <Desc / Clms Page number 119> the numbers take off, after which the transmission of the impulses can resume. 25. A telephony system as claimed in claim 24 wherein the number of control relays which are to operate to give the pause time between each of the digits can be set Immediately, 26. A telephony system as claimed in claim 7 in which the signal takes the form of a modulated alternating current, 27. A telephone system in principle as described and shown in the accompanying plans.