US900458A - Telephone testing system for party-lines. - Google Patents

Telephone testing system for party-lines. Download PDF

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US900458A
US900458A US26302805A US1905263028A US900458A US 900458 A US900458 A US 900458A US 26302805 A US26302805 A US 26302805A US 1905263028 A US1905263028 A US 1905263028A US 900458 A US900458 A US 900458A
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line
circuit
testing
relay
cord
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US26302805A
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Charles S Winston
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Kellogg Switchboard and Supply Co
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Kellogg Switchboard and Supply Co
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    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04MTELEPHONIC COMMUNICATION
    • H04M1/00Substation equipment, e.g. for use by subscribers
    • H04M1/71Substation extension arrangements
    • H04M1/715Substation extension arrangements using two or more extensions per line

Description

c. s'. WINsToN. l TELEPHONE TESTING SYSTEM FOB PARTY LINES.
' PPLcA'rIol Hmm 11u31, 1905.
9O,458. Patented oct. 6,1908.
Cil'.
l ,touch theV tip of ingsubscriber.
CHARLES S. WINSTON,
OF CHICAGO, ILLINOIS, ASSIGNOR TO KELLCGC- ric.
SWITCHBOARD t SUPPLY COMPANY, CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.
- TELEPHONE TESTING SYSTEM FOR PARTY-LINES.
Specification of Letters Patent.
Patented Oct; 6, 1908.
Application sled may a1, 1905. serial No. 263,028.
To all whom t may concern: i y
Be it known that I, CHARLS S. WINSTON,
acitizen of the United StatesV and State of Illinois,
and useful Improvement in Telephonev Testing Systems for Party-Lines, of which the following is a specification.
.My invention relates to a special test sys tem for use on party line telephone systems.
In telephone systems having moreV than,
one station upon a single line when a subscriber calls central and desires to commu nicate withl another subscriber whose station 'is located. upon the same telephone line the operator upon noticing thesignal of the. calling subscriber will insert an answering `plug in the answeringu jack 'of the line of .the call- After ascertaining the num` ber of the station desired the. operator will her calling plug to the test terminal of a multiple jack ofv thelne called for, in the usual manner, to ascertain the idle or -bnsycondition of the line. the fact that the line tested is the line of the calling subscriber as well as the line of the called subscriber,y and tothe fact that the answering plug is connected with the answerline. Peach succeeding time a subscriber upon a denied the provision' of a 4to flowwhen a party line is v'sponse toa call 'from' one of 50 in'gejack of the line, the line will'test busy in the usual manner and the calling subscriber will be informed of the'busy'condition of the The above busy test Willbe .received party line attemptsto call another subscriber upon the saine line unless th'e operator should notice from the numbers of the callving'and calledfor stations that said stations are located upon the same line. During the busy hours of the day the operator would probably not notice tlat suchI was the case and parties upon thesame line would be intel-communication.
inwhich testing current of a special charfacter,4 o r'current adapted to produce ,a special tonein the operators receiver is adapted tested 'in rei the stations upon sa1d'l1r1e..linder such circumstances, in accordance with my invention, a special testingcircuitis closed, which is adapted to 'produce aspecial tone ,in the operators receiver, and notify the operator that the called "station is locatedlupon the same line of, America,v land resident of Chicago, county of Cook,- have' invented a new.
Due to the winding of the line relay being adapted to cont-rol through its normallyopen contacts 22 and 23 the circuit line having as the station of the calling subscriber. The operator upon receiving the test of. special tone will notify the calling subscriber to hang up his receiver the station called for. Upon the response of thecalled subscriber the two stations will lbe in connection for conversation, due to the fact that .the `answering plug inserted in the answering jack of the line.
For the purpose of of my invention, I have illustrated in lthe accompanying` drawing a party line .telephone system, a central office equipment and one method or circuit arrangement for the testing current of special tone.
` In the drawing only two subscribers sta tions-l and 2 are shown although any number of stations may be provided, each of said. stations having a call bell 3 and condenser 4,-- preferably. connected in a permanent bridge f the line conductors, a transmitter 5 and receiver (being connected in a second bridge of the line7 said second bridge having the normal continuity of its circuit broken at the contact point 7 by the" switch hook 8 when the receiver 6 is not in use. It will be revealing the principle f:
until she has signaled 'i understood'that any suitable substation apparatus may be used in lieu of that described. The line 'conductors 9 andA 10 extend from the substations tothe central oflice, said conductors terminating in Contact sprin s 11 and 12, said springs being normally dlsconnected from the tip and sleeve terminals 13 and 14 of the answeringjack 15 of the line. Av Suitable cut-olf relay 16 is legge/d 'to ground from the sleeve terminal lil of the answering jack as shown, said relay being adapted(` to connect the'ljaek. terminals with the -external'line circuit, throughA front contacts 17 and 18 thereof and said line springs 1.1 and 12. One of the back contacts 19 of said relay is connected to ground, the other back contact 20 thereof being connected with relay 21, said line of the line signall 24. The answering jack -15`is shown opposite the answering plug of the cord circuit, themultiple jacks 25 of the their tip contacts 2Gand sleeve contacts 2 legged from the opposite sides thereof, are shown opp0site-the calling plug ofthe cord circui f.
" The operators 'cord 'circuit which I have-'iv shown for the purpose of illustrating the' operation of my invention, is provided with a calling and an answering plug, the tip contact 28 of the answering plug being connected to the tip contact 29 of the calling plug by means of a flexible cord strand 30 containing a condenser 31, the sleeve contacts 32vand 33 of said plugs being similarly united by means of the ileXible strand 34 containing the condenser 35. A central source of current consisting of the battery 36, adapted to furnish current to the substation transmitters and-for operating the signals at the central otlice, is preferably bridged between the strands 39 and 34 of the cord circuit, said bridge consisting of conductors 37 and 38 connecting one pole of said,
battery with the cord strand 30, said conductors including the coils of supervisory relays 39 and 40. The opposite pole of said battery is connected with the cord strand 34 by means of conductors 41 and 42 containing respectively the coils of supervisory relays 43 and 44. One pole of the battery 36 is grounded at 45. A pair of supervisory signal lamps 46 and 53 are connected with one pole of said battery by means of conductors 41 and 47, the circuit of the lamp 46 being controlled through the normally-open contacts 49 and 50 of the supervisory relay 44 and the norn'ially-closed contacts 51 and 52 of the supervisory relay 40. The circuit of supervisory signal 53 is similarly controlled over a circuit including the normally-open contacts of the supervisory relay 43 andthe normally-closed contacts of supervisory relay 39. Theline relay 21 is connected with the battery 36 by means ofconductors 41, 47 and 54.
The operators telephone set, consisting of a transmitter and a condenser included in a local circuit with the primary winding 55 ot an induction coil, is adapted to receive current from the battery 36 over-conductors 56 and 57, a retardation coil 58 preferably being included. in conductor 57. The secondary winding 59 of the induction coil, the oper ators receiver and a condenser, are adapted to be bridged across the strands of the cord circuit by means of a suitable listening key, `one contact of said key being connected with the cord strand 30 by a conductor 60. Cord strand 30 is normally severed by contacts 61 and 62 of the supervisory relay 43, said contacts being adapted to move with but being insulated from the contacts of said relay for controlling the circuit of the supervisory signal 53. A tertiary winding 63 is provided for theoperators induction coil, one ter-` minal of saidwinding bein connect-ed by conductor 64 with one pole o the battery 36,
the opposite pole of whlcb is grounded. The
other side of the tertiary winding is con nected through conductors 66 and 67, normalty-open contacts 68 and 69 of the test re- 6f,lay 70 and conductor 7l, containing impedance coil 7 2, to the ground 7 6. Test relay 70 is preferably of high resistance and high impedance, and 'is connected between the ground 76 and the tip of the calling plug 29 through conductors and 73, a pair of normally-open contacts 74 of the listening' key, conductor 77, normally-closed contacts 7 8 and 62 of the supervisory relay 43 and cord strand 30 to the tip 29. A condenser U3 is bridged between conductors 67 and 73 as shown. A suitable ringing generator 79 is adapted to be bridged across the calling end of the cord circuit for sending ringing current over the line in the usual manner.
In the present instance, in accordance with my invention I provide a rotating current iliterrupter 80, said interrupter being shown in series with primary winding 81 `ot' an induction coil and being preferably connected between the live pole of battery 36 and ground, by means of conductors 41, 47 and 82. The secondary winding 84 of said induction coil is preferably connected with the sleeve cord .strand 34 through a condenser 86, conductor 85, a second pair of normally open-contacts 87 and 88 of the test relay 70 and conductor 65. Contact 88 is adapted to move with but is insulated from, contact 68 of said relay. lt-will be understood that I do not wish to limit my invention to the current interrupter shown nor to the particular method of connecting the saine in circuit above described.
The operation of my invention is as follows: Assuming that subscriber 1 desires to communicate with subscriber 2, he will :re--
move his receiver from the hook 8, thus 36 which may be traced as follows: conductors 41, 47 and 54, winding of line relay 2], back contacts 20 and 11 ot the cut-ott relay 16, line conductor 9, switch hook 8 and contact point 7, transmitter 5, line conductor 10, back contacts 12 and 19 of the cut-olf relay to the grounded pole of the battery 36. The line relay 21 will attract its armature 22 and close the circuit of the line signal 24 from the battery36 in an obvious manner. Upon noticing the signal the operator will insert an answering plug into the answering jack 15. Current will then iiow from battery 36 through conductor 42, supervisory relay 44, sleeve contacts 32 and 14 of the plug and jack and through the cut-off relay 16 to ground, said relay attracting its armatures 11 and 12 and connecting the jack terminals with the limbs of the telephone line through front contacts 17 and 18 of said relay. Cui rent will also flow over line conductor 9 through the substation apparatus, line conductor 1.0, contacts 12 and 18 of the cut-oli` relay, tip contacts 13 and 28 of the jack and plug, cord strand 30, supervisory relay 40 and conductor 38 to battery. The energization of the cut-od relay 16 breaks the circuit 24, and current -29 of the callingv plug,
oogiss l of the line relay 21 at contacts 1l and 2() of the cut-off rela thus retiring the line signal lioiving through the coils of the supervisory relay 44 closes the circuit of the supervisory signal 46 through the normally-open contacts 49 and 50 ofsid relay, but since the subscribers receiver is off its hook the circuit of said supervisory signal is opened at contacts 51 and 52 of the supervisory relay 40, by current the .substation apparatus and through said relay as above described. The supervisory lamp 46 therefore remains inert. The operator then throws her listening key to ascertain the number of the station desired. The operators transmitter may be supplied` with current as shown, from the battery '36.
Assuming that the operator does not notice that-the station with which connection is de fjsired is 'located upon the saine-line as the station of the calling subscriber, ,she will proceed to test .the idle orbusy Vcondition of the line. Due to the fact that the calling subscribers receiver is olf the hook and the answering plug of the cord'circuit is inserted in the answering jack of the line,`the sleeve contacts of the multiple jacks will be raised to a potential above of current from the as above described. 29 to the sleeve, 27 fore, current will flow from'thefisleeve con# tact 27 of the multiple jack, through the tip tip strand 30, norinally-closedcontacts 62 and 78 4of superi battery l36 over the line Upon touching the tip .visory relay 43, conductor 77 contacts74 of the listening key, conductors 73 and 7,5, through the Winding of the .test relay to ground. The test `inlay 70 will attractfits armature 68 which Will close a. path for current from battery 36, over-conductors 41 and 64, tertiary winding '63, conductor-S66 and 67, contacts 68 and 69 of the test ,relay 70,
and conductor I71, including `the re 'ardation coil 72, 'to ground and back tothe battery. The `flow o-f .the above current through the tertiary Windingof the operatorsjinduction coil, `as the tip of the plug is touched tothe test terminal 27, will producethe usual click notifying h er -that .be noted thatthe separates but inthe l-ine is busy. It willcondenser 83 conductively ductively unites, the two paths for current last described.
Upon receiving'a click in her telephone as above described, and failing to notice that the. called station is located upon the samen' line vas the station of the calling subscriber, a
connectionbetween subscribers located upon the same line would-be denied. To remedy such a' contingency and in order to notify thepperator whenever such a condition ex# ists, I ,provide a test duce va testelfect or receiver of a special circuit adapted to proclick 'in the o erators krupter 8() flowing through groundfdue to the flow.4
of the multipleljack therefies the operator tone. It will e :noted- `finto a that a battery 36 over conductors 41, 47 and 82, primary winding 81 of an induction coil, the brushes and contacts of the current interlto ground, and back tothe battery. T is current, due to the action of the rapidly- 'revolving interruptor4 80 or an equivalent circuit breaker, is'inducedin the secondarywinding 84 of said induction coil. When the ltip of the calling plug is touched to the" sleeve of a multiple jack in testing and the,
test relay 70 is energized `as above described, a path for said induced current is closed by contacts 87 and 88 of said relay, being traced as follows: from the winding 84 through condenser 86, conductor 85, contacts 87 and '88 ofthe test relay, c0nductor 65, sleeve conductor'34, sleeve contacts 32 and 14 of the answering plu and jack, contacts 17 and 11 of the cut-o relay, line conductor 9, test ter'ininal 27 of the multiple jack, tip 29 of the 'calling plug, cord conductor 30, contacts 62 and 78 of the supervisory`relay 43, conductor 77, contacts 74 of the listening key, conductor 73, condenser 83,
secondary conductor 66, tertiary winding 63, conductor 64 and battery 36 to ground. It will be noted that while the condenser 83 is opaque to the direct current -flowing in the two paths heretofore described, between which said condenser is bridged, parent to the high frequency induced current above'described, the high impedance of the -test relay 70 preventing said current from 'passing to ground upon one side of said con- A`denser and the impedance coil 72 preventing the induced currentv from passing to the :ground 76 upon the other sideof said condenser. `TheV induced current flowing from the secondary Winding-84 through the tertiary 4Winding of the operators induction coil produces a click in her receiver different in .path for current is provided from thel said path j said condenser is trans.
tone from the click produced therein by the t .flow of direct .current from the battery 36,
said difference being due in part to the rapidity at which the current interrnpter is rotated, said click of special tone serving to notify the operator that the station is upon th It will be desired e saine l'ine as the calling station.' noted that Vas the path of said test circuit ,of-special tone is through the contacts of the answering jack and over a line conductor to the test terminal ofoa multiple jackl ofthe line, said special test would not be received'by the operator when the answering plug was 'inserted in the jack of a different line from the one tested.
Upon receiying the special test which notithat sthtien-2 is upon the saine line as the station ofthe calling sub scriber, -she will request. the callii'ig sub, scriber to replace his receiver u 'the .hook unti the subscriber at station -2Ihas' been nale She will then insert the calling plug` multiple jack of the line, depress hei.'
ringing key and send ringing current over the line in the usual manner to operate the `bell of the called subscriber. After signaling the called subscriber, the operator will withdraw the calling plug from the multiple ack of the line and the 'subscribers will then he connected for conversation, current flowing from the battery 36 over4 the line, as above described, and through substations l and 2 in multiple, for the actuation of the substation transmitters.-
lVhen diit'erent lines are connected for coiiversation by means of the central station apparatus illustrated, current iows through supervisory relays 39 and 43 and over the ip and sleeve cord strands from battery 3G in the saine manner as that. described with reference to supervisory relays LO and Llc-ZL, but as said portion of the central station apparatus is inoperative during a connection between subscribers upon the same line, it is not thought advisable to describe the circuits of suoli part of the central station apparatus in detail, the' circuit of the other portion of said apparatus clearly illustrating the operation of the special test circuit. Upon the conclusion of the conversation the subscribers return their receivers to their respective hooks, thus breaking the circuit flow over the line and through the supervisory relay 40, which releases its armature 52, closing the circuit of the supervisory lamp 46. Upon noticing the signal the operator will remove the answering plug 28 from the ack 15 'which will restore all parts to normal condition. v
It will be understood that the special test circuit illustratecLis intended to represent only one method of embodying my invention in a practical form and said circuit arrangement as illustrated may be changed without departing fromftlie spirit of my invention.
that claim as new and desire to secure by Letters Patent is: e
1. In a testing system, the combination with a telephone .line having a busy testing terminal, of an operators testing contact for testing the busy condition of the line, a testing circuit including a portion of the talking circuit of the answering end of the cord adapted to .be closed when a busy line is tested, and means associated with said circuit .for interrupting the current low therein,
circuit for interrupting the current Illow therein, whereby when a busy line tested a special tone is produced in the operators receiver, substantially as described.
3. In a testing system, the combination with a telephone line hafving a busy testing terminal, ot an operators testing contact for testing the busy condition of the line, an alternating current testing circuit, an elect romagnetic device itor connecting said circuit with the answering end olE the sleeve voice current conductor when a 'busy line is tested, said circuit being` adapted to produce a special tone in the operator`sl receiver, substantially as described.
4. T.n a testing system, the combination with a telephone line having a busy testing terminal, of a cord circuit for making connection with the line, an ope ators testing contact for testing the busy condition of the line connected with the tip strand of the cord circuit, and an alternating current testing circuit including a portion of the answering end of the sleeve talking strand, said circuit being adapted to -produce a special (one in the operators receiver when a busy line is tested, substantially as described.
In a testing system, Athe combination with a telephone line having a busy testing terminal, ol a cord circuit for making connection with the line, an operatoi"s testing contact for testing the busy condition otI the line, an alternating current testing circuit including a portion of the sleeve strand of the c ord circuit and a line conductor, and means for closing said circuit when a busy line is tested, said circuit being adapted to produce a special tone in the opcrators rcceiver, substantially as described.
(3. ln a testing system, the combination with a telephone line having a busy testing terminal, of a cord circuit for making connection with the line, an oporators testing contact associated with the tip strand of the cord circuit for testing the busy condition of the line, and an induced alternating current testing circuit including a sleeve strand of the cord circuit and a line conductor, said circuit being adapted to produce a special tone in the operato1"s receiver when a busy line is tested "ubstantially as described.
7. In a testing system, the combination with a telephone line having a busy testing terminal, of a cord circuit. for making con nection with the line, an operators testing contact for testing the busy condition of the line, a .direct current. testing circuit, an aL ternating current testing circuit including a sleeve strand of the cord circuit and a por tion of one line conductor,-'and electro-magnetic means for closing both Asaid circuits when a busy line is tested', said alternating current circuit being adapted to produce a special tone in the operators receiver, substantially as described.
'ffrupte'd current testing circuit, substantially phonel line extending from said stations to ai central oliice, a plurality of connecting'coning end of the cord circuit, only'. when said with said 'cord'ciruit,'a signal .circuit adapt'- tially as described.
. with said cord Vcircuit,a signal circuit adaptthe answering end of with the test contact of `thecalling line, and y al of dierent charac- Va cord circuit having tip and sleeveistrands for making connection with the line for conversation, a direct current testing circuit and and the energizing circuit for said relay, said `10. In a! iisysteiiif'tlie"combination with a pluralitybf substation'slocated upon a' telephone line, bfa pluralityof. connecting 'nal anda portion ofthe ltalking circuit of stations upon said line, an
.line has been`tested,- substantially as ,de-
f 900,45e y 8. Ina testing system, the'combinationiof a telephone line having a testing terminal, vof
an interrupted current testing circuit a test relay for-closing saidcircuits energizeover the tip cord strand, and a condenser bridged etween' said directcurrent testing circuit condenser being 1n the i path lof. said interas described.
9. In a testing system, 4the combination with apluralityl of substations, of .a telecuit will be -v completed over said testing' terminal associated Wit-h said cord circuit, a testing circuit and means `whereby said circuit will. be completed over said testing terminal and atalking strand .of the answer-` line is 1n connection with the answering end.' ofsaid cord circuit, substantie. y as des` scribedyp" contacts -for said .linelat the central oiiice, `a cord circuit, a testingl terminal associated ed to be closedover l'saidlv testing terminal when said line is in connection with, a second cordcircuit, and a different. signal c1rcu1t adapted. to be closed over said testing termithe answering end of the cord circuit, when said line is in connection with fthe answering end. of said li'rst cord circuit, said testing cir'` cuits transmitting signals of diii'erent characteristic sounds tothe pperator, substan- 11. In a test' system, the combination with a telephone ine, of a lurality of subd a plurality iof test contacts for said line at the central oce, a cord circuit, a testingterminal associated ed to be closed over said testing terminal andthe sleeve talking strand of a 'cord circuit when it is connecte means whereby as' ter will indicate whena different telephone scribed. system, the comblnatlon 1a. In a testing'.` with a telephone me, of a lurality of substations upon said` line, 'an
a plurality of 'substantially as described.
with a telephone testinggcontaets fori said line at the central `oiiicefa cord circuit, a testing terminal associate with said cord eircuit, a busytest circuit adapted-to be closed-When the cord test terminal is connected to the test'terminal of the busy line, and a tone'` signal circuit adapted to be closed over a portion pf the answering end of the sleeve talking strand when said line is busy by its connection with tivesign'al one beino' completed over the an I swering end of the s eeve talking strand of acircuit said circuits being adapted to' 'be closed under different busycondi'tions of the condition of cord said telephone line whereb the line-may be determine by the busy test,
14'.. In a testing system, the combination with a .cord circuit, sof a testing conductor -for said cord circuit,"'including the coil of a .test relay, a distinctive current-adapted by the' actuation ofsaidtest' relay to be connected with the answering end of one of the talking strands of" said cord circuit, and means when the answering end of said cord circuit-isfconnected to Vone of the jacks of 'the telephone 'line,vwhereby said distinctive current will be inductivel the operator-s receiver w en said testing conductor isfconnected to another terminal of said line, substantially as described. g 15. Ina testing the combination ine having a plurality of subscribers connected. therewith, of a plutransmitted to rality of testing terminalsconnected with'.
one'of the talking strands of said line during conversation, and means for connecting a distinctive current with the test contact of said telephone line whenv one subscriber of said rio line requests connection with a second sub# scriber of the same line, substantially as described.
witnesses.
n CHARLES S. WINSTON.-
Witnesses:
C.l B. CAMP, E. F. Garan.
Signed by vme at Chicago, county of Cook, and State of Illinois, in the presence of two
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