US3140353A - Party line identification system - Google Patents

Party line identification system Download PDF

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US3140353A
US3140353A US187306A US18730662A US3140353A US 3140353 A US3140353 A US 3140353A US 187306 A US187306 A US 187306A US 18730662 A US18730662 A US 18730662A US 3140353 A US3140353 A US 3140353A
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relay
stations
line
rotary switch
circuit
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US187306A
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Sherstiuk Boris
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Automatic Electric Laboratories Inc
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    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04MTELEPHONIC COMMUNICATION
    • H04M1/00Substation equipment, e.g. for use by subscribers
    • H04M1/26Devices for calling a subscriber
    • H04M1/53Generation of additional signals, e.g. additional pulses
    • H04M1/54Arrangements wherein a dial or the like generates identifying signals, e.g. in party-line systems

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  • This invention relates to arrangements for identifying calling stations on multi-party lines in automatic telephone systems and more particularly, to impulse detecting circuits in such arrangements.
  • each of the party subscribers on a multiparty line is provided with a conventional dial operated impulse transmitter in which a main impulsing cam periodically opens the line circuit to transmit a series of impulses in a well-known manner to operate an impulsing relay.
  • the line circuit is normally closed through one winding of an electropolar relay, the current in the line circuit and through this winding supporting the action of a second current through a second winding of this relay which second current holds the armature of the electropolar relay in a first operated position.
  • This periodic opening of the line circuit when no current flows through the said first winding will have no effect upon the second winding and the said armature will remain in its first operated position.
  • an auxiliary impulsing cam co-rotatable with the main impulsing cam and adapted to periodically close an identification impulsing circuit in a predetermined sequential relationship with the peri odic opening of the line circuit.
  • This identification impulsing circuit is also periodically closed through the said one winding of the said electropolar relay, the current in the last-named identification impulsing circuit however flowing in a direction opposing the action of the current through the said second winding of the electropolar relay.
  • the current in the said one winding is now effective to move the said armature to a second operated position and registering circuits controlled by the armature of the electropolar relay can be energized in accordance with the identification impulses generated by the auxiliary impulsing cam.
  • stations three and four are equipped with spotter dials of the type described in Patent No. 2,822,424 issued to J. E. Ostline on February 4, 1958, which application and patent are made a part hereof by reference.
  • the station number two dial is equipped with a tip ground leak.
  • This arrangement requires that the spotter pulse from the spotter dial be detected when the dial impulse repeating relay is operated and the leak to ground when the impulse repeating relay is released. With this arrangement there is a possibility of mistaking the tip ground leak for a spotter pulse should the impulse repeating relay fail to release fast enough. As a result severe adjustment requirements are placed on the impulse repeating relay to prevent this possibility.
  • the primary object of the present invention is to provide an improved identification circuit operated in response to the operation of the identification impulsing cam of the dial operated impulse transmitter.
  • an impulse counting device such as a rotary switch discriminating between the numbers of impulses received.
  • the present invention theresixty milliseconds.
  • the four party line stations are shown only as dials designated as SP1, SP2, SP3 and SP4, connected via the common line conductors 13 and 14 and the switching equipment shown symbolically only as banks and associated wipers to the party detecting equipment.
  • This equipment which requires only 3 relays and a rotary switch may be part of a complete ticketer circuit as disclosed for example in the Edward J. Glenner application.
  • a pulse is a sudden change of brief duration produced in a current or voltage of a circuit in order to actuate or control a switch or relay.
  • a typical dial pulse in telephony is produced by opening the loop circuit for a period of approximately Where pulses are generated in a series, such as the ten pulses generated by the dialing of zero, the sixty millisecond open periods are separated by closed periods of approximately forty milliseconds.
  • a dial operated impulse transmitting device represented at SP3 is provided with a digital impulsing cam 11 with which are operatively associated the break contacts 12, the contacts 12 are included in series with a conventional line circuit by means of the conductors 13 and 14. Also included in the line circuit after connection through the switching equipment to the register circuit is an impulsing relay AA having the make contacts AAl associated therewith.
  • the relay AA is well-known and may be of the type disclosed in the Edward I. Glenner application.
  • Completing the line circuit are a suitable source of potential 15, a resistance lamp 16 and a polar-relay PA having the make contacts PA1.
  • an identification impulsing cam 10 with which are operatively associated the make contacts 17.
  • the contacts 17 are included in series with an identification impulsing circuit which may be traced from ground through the contacts 17, conductor 14, polar-relay PA, the resistance lamp 16, and spotter battery 18, to ground.
  • party number one and two employ a subset equipped with a dial without the identification cam, and springs such as 10 and 17, however the party number twos subset is equipped to provide a tip ground leak from the dial shunt springs during dialing.
  • This tip resistance ground mark for party number two is placed on the line during the line breaks to close the circult to relay PA.
  • Relay PA operates on the first line break and closes a circuit at contacts PAl from ground potential via other circuits shown only as a dotted line to the B" wiper of rotary switch PSW, associated contact N to the motor magnet of switch PSW and also to the winding of relay PB through the off normal springs 0N2 of switch PSW.
  • the rotary switch PSW operates its armature to step the associated wipers A and B upon deenergization, and also opens the circuit to the winding of relay PB.
  • Relay PB will release since the circuit completed at contacts P131 is open due to the released condition of relay AA.
  • Relay PA will operate to attempt to step the rotary switch PSW for as many steps as there are open periods for the digit dialed by the calling subscriber.
  • parties 3 and 4 transmit only a single marking pulse during the dialing of any digit and the party identity is received after the second digit is dialed, it is obvious that the receipt of more than two pulses signifies party number two.
  • the rotary switch PSW bank level B has its first three contacts strapped with the switch normal position, to stop the switch from stepping beyond the third step for a party number two determination.
  • the party is then marked from a ground potential via other circuits through the Wiper on the third contact of the bank level A to terminal P2 indicating the detected partly as number 2.
  • the rotary switch is reset from other circuitry not essential to this disclosure and shown only as a ground potential RS1 through the N1 contacts.
  • Party number three employs a special dial that sends out a ground pulse during the next to last line break which remains on the line when the line loop is closed and relay AA is operated.
  • Relay PA operates when the ground mark is present and closes a circuit to rotary switch PSW and relay PB.
  • Relay PB operates, but is released during the following line break when the 0N2 contacts are open and relay AA falls back.
  • the rotary switch PSW operates its armature to step the associated wipers A and B upon deenergization.
  • Party number four also employs a special dial but this time one that sends out a ground pulse at the end of the first digit when relay AA is operated.
  • Relay PA operates from this ground pulse and closes the circuit to rotary switch PSW and relay PB.
  • the rotary switch PSW operates its armature to step the associated wipers A and B upon deenergization.
  • Relay PB operates from the ground potential via bank level B and the 0N2 contacts and momentarily locks to the ground potential from contacts AAll.
  • HG is applied from other circuitry to hold relay PB operated.
  • relay PB is now held from HG.
  • the detected calling party is then marked from a ground potential via other circuits through the wiper on the first or second contact of the bank level A through make contacts PBZ to terminal P4, indicating the detected party as number 4.
  • the calling party identity can be determined reliably even if the first or second digit dialed into the register is 2 or greater.
  • the circuit after utilization of the calling party information is reset to normal in any well known manner, such as the application of ground potential through olf normal contacts such as 0N1 to step it home.
  • a system for identifying the calling stations of a party line during the interval of the dialing of the first two digits of a called number including a line having four stations connected thereto, each of said stations having a pulsing device and an identifying designation, a first one of said stations pulsing device including marking means for applying a ground potential to said line during each line break of said pulsing device, a second one of said stations pulsing device including a marking means for applying a ground potential to said line during the penultimate impulse of said pulsing device and a third one of said stations pulsing device including a means for applying a ground potential to said line during the last impulse of said pulsing device;
  • a calling station identity detecting means including a digital impulse responsive first relay including a pair of make contacts controlled by said pulsing means, an identification impulse responsive second relay controlled by said marking means, make contact means controlled by said second relay, a rotary switch including an actuating magnet and a first and a second wiper and bank assembly, an operating circuit for said magnet including said make contact means on said second relay, said second wiper and a normally made contact of said second bank assembly to step said rotary switch once for each operation of said second relay, a party discriminating circuit means including the strapping of the first two bank contacts of said second bank assembly whereby said rotary switch operating circuit is interrupted after a third ground potential pulse, and circuit means for indicating said first station upon the rotary switch taking a third step, including said first wiper and third contact of said first bank assembly of said rotary switch to mark said first station as the calling station.
  • the combination as claimed in claim 1 including a pair of off-normal break contacts on said rotary switch, a third relay including a pair of make contacts and a set of transfer contacts, an operating circuit for said third relay including said make contacts on said second relay, said second wiper a normally made contact of said second bank assembly and said pair of off-normal contacts, means including said rotary switch and said third relay operated in response to the ground impulse of said dial at said last-mentioned station to complete a station marking circuit including said first wiper and bank assembly and said operated transfer contacts.
  • the combination as claimed in claim 2 including a holding circuit means for said third relay comprising said pair of make contacts of said first relay, said pair of make contacts of said third relay and a second winding of said third relay operated upon operation of said third relay.
  • the combination as claimed in claim 2 comprising a circuit means including the circuit of said line relay make contacts opened in response to the ultimate digital pulse following said ground impulse upon initiation of a call from said other station to release said third relay to complete a corresponding station marking circuit including said first wiper and bank assembly and said released transfer contacts.

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  • Engineering & Computer Science (AREA)
  • Signal Processing (AREA)
  • Monitoring And Testing Of Exchanges (AREA)

Description

July 7, 1964 B. SHERSTIUK PARTY LINE IDENTIFICATION SYSTEM Filed April 13, 1962 INVENTOR. Boris Shersfiuk Affy United States Patent tric Laboratories, line, Northlake, Ill., a corporation of Delaware Filed Apr. 13, 1962, Ser. No. 187,306 4 Claims. (Cl. 17917) This invention relates to arrangements for identifying calling stations on multi-party lines in automatic telephone systems and more particularly, to impulse detecting circuits in such arrangements. In one arrangement heretofore known each of the party subscribers on a multiparty line is provided with a conventional dial operated impulse transmitter in which a main impulsing cam periodically opens the line circuit to transmit a series of impulses in a well-known manner to operate an impulsing relay. The line circuit is normally closed through one winding of an electropolar relay, the current in the line circuit and through this winding supporting the action of a second current through a second winding of this relay which second current holds the armature of the electropolar relay in a first operated position. This periodic opening of the line circuit when no current flows through the said first winding will have no effect upon the second winding and the said armature will remain in its first operated position.
In the dial operated impulse transmitter of the known arrangement is also provided an auxiliary impulsing cam co-rotatable with the main impulsing cam and adapted to periodically close an identification impulsing circuit in a predetermined sequential relationship with the peri odic opening of the line circuit. This identification impulsing circuit is also periodically closed through the said one winding of the said electropolar relay, the current in the last-named identification impulsing circuit however flowing in a direction opposing the action of the current through the said second winding of the electropolar relay. The current in the said one winding is now effective to move the said armature to a second operated position and registering circuits controlled by the armature of the electropolar relay can be energized in accordance with the identification impulses generated by the auxiliary impulsing cam.
In a four party identification scheme according to a modification of the above arrangement disclosed in the copending application of Edward I. Glenner, Serial No. 70,526, filed November 21, 1960, stations three and four are equipped with spotter dials of the type described in Patent No. 2,822,424 issued to J. E. Ostline on February 4, 1958, which application and patent are made a part hereof by reference. The station number two dial is equipped with a tip ground leak. This arrangement requires that the spotter pulse from the spotter dial be detected when the dial impulse repeating relay is operated and the leak to ground when the impulse repeating relay is released. With this arrangement there is a possibility of mistaking the tip ground leak for a spotter pulse should the impulse repeating relay fail to release fast enough. As a result severe adjustment requirements are placed on the impulse repeating relay to prevent this possibility.
The primary object of the present invention is to provide an improved identification circuit operated in response to the operation of the identification impulsing cam of the dial operated impulse transmitter. According to the principal feature of this invention there is substituted in the aforementioned identification impulsing circuit the combination of an impulse counting device such as a rotary switch discriminating between the numbers of impulses received. The present invention theresixty milliseconds.
by provides an identification impulsing circuit responding to a dial operated identification cam which will be positive in operation and will at the same time be relatively simple.
It is another object of this invention to provide an identification impulsing circuit the components of which are economical to procure, are durable and will require a minimum amount of adjustment.
Other objects and features of this invention will become apparent from a perusal of the detailed description of the invention which follows. Illustrating one embodiment of the present invention is the single figure of the drawings showing in schematic form the relationship of the circuit components.-
The four party line stations are shown only as dials designated as SP1, SP2, SP3 and SP4, connected via the common line conductors 13 and 14 and the switching equipment shown symbolically only as banks and associated wipers to the party detecting equipment. This equipment which requires only 3 relays and a rotary switch may be part of a complete ticketer circuit as disclosed for example in the Edward J. Glenner application.
For purposes of this specification, a pulse is a sudden change of brief duration produced in a current or voltage of a circuit in order to actuate or control a switch or relay. A typical dial pulse in telephony is produced by opening the loop circuit for a period of approximately Where pulses are generated in a series, such as the ten pulses generated by the dialing of zero, the sixty millisecond open periods are separated by closed periods of approximately forty milliseconds.
In my invention a dial operated impulse transmitting device represented at SP3 is provided with a digital impulsing cam 11 with which are operatively associated the break contacts 12, the contacts 12 are included in series with a conventional line circuit by means of the conductors 13 and 14. Also included in the line circuit after connection through the switching equipment to the register circuit is an impulsing relay AA having the make contacts AAl associated therewith. The relay AA is well-known and may be of the type disclosed in the Edward I. Glenner application. Completing the line circuit are a suitable source of potential 15, a resistance lamp 16 and a polar-relay PA having the make contacts PA1. Also provided in the dial impulse transmitting device SP3 is an identification impulsing cam 10 with which are operatively associated the make contacts 17. The contacts 17 are included in series with an identification impulsing circuit which may be traced from ground through the contacts 17, conductor 14, polar-relay PA, the resistance lamp 16, and spotter battery 18, to ground.
In four-party identification, party number one and two employ a subset equipped with a dial without the identification cam, and springs such as 10 and 17, however the party number twos subset is equipped to provide a tip ground leak from the dial shunt springs during dialing. This tip resistance ground mark for party number two is placed on the line during the line breaks to close the circult to relay PA. Relay PA operates on the first line break and closes a circuit at contacts PAl from ground potential via other circuits shown only as a dotted line to the B" wiper of rotary switch PSW, associated contact N to the motor magnet of switch PSW and also to the winding of relay PB through the off normal springs 0N2 of switch PSW. The rotary switch PSW operates its armature to step the associated wipers A and B upon deenergization, and also opens the circuit to the winding of relay PB. Relay PB will release since the circuit completed at contacts P131 is open due to the released condition of relay AA. Relay PA will operate to attempt to step the rotary switch PSW for as many steps as there are open periods for the digit dialed by the calling subscriber. However, since parties 3 and 4 transmit only a single marking pulse during the dialing of any digit and the party identity is received after the second digit is dialed, it is obvious that the receipt of more than two pulses signifies party number two. Therefore the rotary switch PSW bank level B has its first three contacts strapped with the switch normal position, to stop the switch from stepping beyond the third step for a party number two determination. The party is then marked from a ground potential via other circuits through the Wiper on the third contact of the bank level A to terminal P2 indicating the detected partly as number 2. The rotary switch is reset from other circuitry not essential to this disclosure and shown only as a ground potential RS1 through the N1 contacts.
If this is party number one, no resistance ground is present on the T side of the line and relay PA will not be operated. The calling party is then marked from the ground potential through the wiper on the normal contact of the bank level A to terminal P1, indicating the de tected party station as number 1.
Party number three employs a special dial that sends out a ground pulse during the next to last line break which remains on the line when the line loop is closed and relay AA is operated. For a detailed disclosure of this dial see Patent No. 2,822,424 issued to J. E. Ostline on February 4, 1958. Relay PA operates when the ground mark is present and closes a circuit to rotary switch PSW and relay PB. Relay PB operates, but is released during the following line break when the 0N2 contacts are open and relay AA falls back. The rotary switch PSW operates its armature to step the associated wipers A and B upon deenergization. During the dialing of the second digit switch PSW will again take a single step as described but relay PB will not operate since its circuit is held open at contacts 0N2. The detected calling party is then marked from a ground potential via other circuits through the wiper on the first or second contact of the bank level A to terminal P3, indicating the detected party as number 3.
Party number four also employs a special dial but this time one that sends out a ground pulse at the end of the first digit when relay AA is operated. Relay PA operates from this ground pulse and closes the circuit to rotary switch PSW and relay PB. The rotary switch PSW operates its armature to step the associated wipers A and B upon deenergization. Relay PB operates from the ground potential via bank level B and the 0N2 contacts and momentarily locks to the ground potential from contacts AAll. During the interdigital pause before the second digit is dialed locking ground HG is applied from other circuitry to hold relay PB operated. During the dialing of the second digit switch PSW will again take a single step as described, but relay PB is now held from HG. The detected calling party is then marked from a ground potential via other circuits through the wiper on the first or second contact of the bank level A through make contacts PBZ to terminal P4, indicating the detected party as number 4.
Thus it can be seen that the calling party identity can be determined reliably even if the first or second digit dialed into the register is 2 or greater.
The circuit after utilization of the calling party information is reset to normal in any well known manner, such as the application of ground potential through olf normal contacts such as 0N1 to step it home.
While a specific embodiment of the invention has been described, it is to be clearly understood that this description is made only by Way of example and not as a limitation to the scope of the invention.
What is claimed is:
1. In a system for identifying the calling stations of a party line during the interval of the dialing of the first two digits of a called number, including a line having four stations connected thereto, each of said stations having a pulsing device and an identifying designation, a first one of said stations pulsing device including marking means for applying a ground potential to said line during each line break of said pulsing device, a second one of said stations pulsing device including a marking means for applying a ground potential to said line during the penultimate impulse of said pulsing device and a third one of said stations pulsing device including a means for applying a ground potential to said line during the last impulse of said pulsing device;
the other end of said line provided with a calling station identity detecting means including a digital impulse responsive first relay including a pair of make contacts controlled by said pulsing means, an identification impulse responsive second relay controlled by said marking means, make contact means controlled by said second relay, a rotary switch including an actuating magnet and a first and a second wiper and bank assembly, an operating circuit for said magnet including said make contact means on said second relay, said second wiper and a normally made contact of said second bank assembly to step said rotary switch once for each operation of said second relay, a party discriminating circuit means including the strapping of the first two bank contacts of said second bank assembly whereby said rotary switch operating circuit is interrupted after a third ground potential pulse, and circuit means for indicating said first station upon the rotary switch taking a third step, including said first wiper and third contact of said first bank assembly of said rotary switch to mark said first station as the calling station.
2. In a system for identifying the calling stations of a party line, the combination as claimed in claim 1 including a pair of off-normal break contacts on said rotary switch, a third relay including a pair of make contacts and a set of transfer contacts, an operating circuit for said third relay including said make contacts on said second relay, said second wiper a normally made contact of said second bank assembly and said pair of off-normal contacts, means including said rotary switch and said third relay operated in response to the ground impulse of said dial at said last-mentioned station to complete a station marking circuit including said first wiper and bank assembly and said operated transfer contacts.
3. In a system for identifying the calling stations of a party line, the combination as claimed in claim 2 including a holding circuit means for said third relay comprising said pair of make contacts of said first relay, said pair of make contacts of said third relay and a second winding of said third relay operated upon operation of said third relay.
4. In a system for identifying the calling stations of a party line, the combination as claimed in claim 2 comprising a circuit means including the circuit of said line relay make contacts opened in response to the ultimate digital pulse following said ground impulse upon initiation of a call from said other station to release said third relay to complete a corresponding station marking circuit including said first wiper and bank assembly and said released transfer contacts.
References Cited in the file of this patent UNITED STATES PATENTS 2,619,546 Myers Nov. 25, 1952 2,785,228 Gulbrandsen Mar. 12, 1957 3,024,316 Ostline Mar. 6, 1962 3,046,349 Molnar July 24, 1962

Claims (1)

1. IN A SYSTEM FOR IDENTIFYING THE CALLING STATIONS OF A PARTY LINE DURING THE INTERVAL OF THE DIALING OF THE FIRST TWO DIGITS OF A CALLED NUMBER, INCLUDING A LINE HAVING FOUR STATIONS CONNECTED THERETO, EACH OF SAID STATIONS HAVING A PULSING DEVICE AND AN IDENTIFYING DESIGNATION, A FIRST ONE OF SAID STATIONS PULSING DEVICE INCLUDING MARKING MEANS FOR APPLYING A GROUND POTENTIAL TO SAID LINE DURING EACH LINE BREAK OF SAID PULSING DEVICE, A SECOND ONE OF SAID STATIONS PULSING DEVICE INCLUDING A MARKING MEANS FOR APPLYING A GROUND POTENTIAL TO SAID LINE DURING THE PENULTIMATE IMPULSE OF SAID PULSING DEVICE AND A THIRD ONE OF SAID STATIONS PULSING DEVICE INCLUDING A MEANS FOR APPLYING A GROUND POTENTIAL TO SAID LINE DURING THE LAST IMPULSE OF SAID PULSING DEVICE; THE OTHER END OF SAID LINE PROVIDED WITH A CALLING STATION IDENTITY DETECTING MEANS INCLUDING A DIGITAL IMPULSE RESPONSIVE FIRST RELAY INCLUDING A PAIR OF MAKE CONTACTS CONTROLLED BY SAID PULSING MEANS, AN IDENTIFICATION IMPULSE RESPONSIVE SECOND RELAY CONTROLLED BY SAID MARKING MEANS, MAKE CONTACT MEANS CONTROLLED BY SAID SECOND RELAY, A ROTARY SWITCH INCLUDING AN ACTUATING MAGNET AND A FIRST AND A SECOND WIPER AND BANK ASSEMBLY, AN OPERATING CIRCUIT FOR SAID MAGNET INCLUDING SAID MAKE CONTACT MEANS ON SAID SECOND RELAY, SAID SECOND WIPER AND A NORMALLY MADE CONTACT OF SAID SECOND BANK ASSEMBLY TO STEP SAID ROTARY SWITCH ONCE FOR EACH OPERATION OF SAID SECOND RELAY, A PARTY DISCRIMINATING CIRCUIT MEANS INCLUDING THE STRAPPING OF THE FIRST TWO BANK CONTACTS OF SAID SECOND BANK ASSEMBLY WHEREBY SAID ROTARY SWITCH OPERATING CIRCUIT IS INTERRUPTED AFTER A THIRD GROUND POTENTIAL PULSE, AND CIRCUIT MEANS FOR INDICATING SAID FIRST STATION UPON THE ROTARY SWITCH TAKING A THIRD STEP, INCLUDING SAID FIRST WIPER AND THIRD CONTACT OF SAID FIRST BANK ASSEMBLY OF SAID ROTARY SWITCH TO MARK SAID FIRST STATION AS THE CALLING STATION.
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Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2619546A (en) * 1946-05-29 1952-11-25 Bell Telephone Labor Inc Party line identification system
US2785228A (en) * 1955-06-06 1957-03-12 Automatic Elect Lab Party line identification and checking circuit
US3024316A (en) * 1956-12-03 1962-03-06 Automatic Elect Lab Calling line and station identification system
US3046349A (en) * 1959-04-27 1962-07-24 Automatic Elect Lab Station identification apparatus

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2619546A (en) * 1946-05-29 1952-11-25 Bell Telephone Labor Inc Party line identification system
US2785228A (en) * 1955-06-06 1957-03-12 Automatic Elect Lab Party line identification and checking circuit
US3024316A (en) * 1956-12-03 1962-03-06 Automatic Elect Lab Calling line and station identification system
US3046349A (en) * 1959-04-27 1962-07-24 Automatic Elect Lab Station identification apparatus

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