235:
346:
another extension, the operator places the front cord in the associated jack and pulls the front key backwards to ring the called party. After connecting, the operator leaves both cords "up" with the keys in the normal position so the parties can converse. The supervision lamps light to alert the operator when the parties finish their conversation and go on-hook. Either party could "flash" the operator's supervision lamps by depressing their switch hook for a second and releasing it, in case they needed assistance with a problem. When the operator pulls down a cord, a pulley weight behind the switchboard pulls it down to prevent it from tangling.
151:
20:
291:
97:
1560:
231:
would try alternate routings through intermediate cities. The operator would plug into a trunk for the destination city, and the inward operator would answer. The inward operator would obtain the number from the local information operator, and ring the call. Once the called party answered, the originating operator would advise him or her to stand by for the calling party, whom she'd then ring back, and record the starting time, once the conversation began.
1570:
1549:
1580:
259:(a fast busy signal), it could indicate "all circuits busy," or a problem in the destination exchange. The operator might be able to use a different routing to complete the call. If the operator could not get through by dialing the number, she could call the inward operator in the destination city, and ask her to try the number, or to test a line to see if it was busy or out of order.
266:(TSPS) and similar systems, which greatly reduced operator involvement in calls. The customer would, instead of simply dialing "0" for the operator, dial 1+NPA+7digits, after which an operator would answer and provide the desired service (coin collection, obtaining acceptance on a collect call, etc.), and then release the call to be automatically handled by the TSPS.
330:. Each of the keys has three positions: back, normal and forward. When a key is in the normal position an electrical talk path connects the front and rear cords. A key in the forward position (front key) connects the operator to the cord pair, and a key in the back position sends a ring signal out on the cord (on older manual exchanges). Each cord has a three-wire
230:
The long-distance operator would record the name and city of the person to be called, and the operator would advise the calling party to hang up and wait for the call to be completed. Each toll center had only a limited number of trunks to distant cities, and if those circuits were busy, the operator
273:
In the mid-1980s the Bell
Operating Companies (BOCs) opened their own Operator Services offices with a system called TOPS (Traffic Operator Position System) to act as local and intraLATA telephone operators. With this the BOCs took intraLATA call traffic from AT&T as well as services which were
200:
Early switchboards in large cities usually were mounted floor to ceiling in order to allow the operators to reach all the lines in the exchange. The operators were boys who would use a ladder to connect to the higher jacks. Late in the 1890s this measure failed to keep up with the increasing number
281:
As technology changed, so did the application of
Interflow. Interflow was implemented nationwide by AT&T. This allowed AT&T to close virtually every operator office throughout the US. As of 2004 the only AT&T operator offices remaining were located in Houston, Texas, and Jacksonville,
277:
In the early 1990s AT&T replaced TSPS with OSPS (Operator
Service Position System). The OSPS position was a computer terminal which the AT&T operator entered billing information. With the advent of OSPS a feature called Interflow allowed operators on a system to answer calls from anywhere
180:
In
January 1878 the Boston Telephone Dispatch company had started hiring boys as telephone operators. Boys had been very successful as telegraphy operators, but their attitude, lack of patience, and behavior was unacceptable for live telephone contact, so the company began hiring women operators
269:
Before the late 1970s and early 1980s, it was common for many smaller cities to have their own operators. An NPA (area code) would usually have its largest city as its primary toll center, with smaller toll centers serving the secondary cities scattered throughout the NPA. TSPS allowed telephone
250:
operator dialing, the operator would plug into a tandem trunk and dial the NPA (area code) and operator code for the information operator in the distant city. For instance, the New York City information operator was 212-131. If the customer knew the number, and the point was direct-dialable, the
254:
In the 1960s, once most phone subscribers had direct long-distance dialing, a single type of operator began to serve both the local and long-distance functions. A customer might call to request a collect call, a call billed to a third number, or a person-to-person call. All toll calls from coin
345:
When a call is received, a jack lamp lights on the back panel and the operator responds by placing the rear cord into the corresponding jack and throwing the front key forward. The operator then converses with the caller, who informs the operator to whom he or she would like to speak. If it is
357:
signals must pass in both directions. In a one-way trunk, the originating or A board sends a short for off-hook, and an open for on-hook, while the terminating or B board sends normal polarity or reverse polarity. This "reverse battery" signaling was carried over to later automatic exchanges.
176:
installed the first central office and switchboard that served both as a security service at night for banks and businesses, as well as a telephone system. The switchboard operated telephone instruments manufactured by
Charles Williams, a licensee of the Alexander Graham Bell company.
209:
for operators to work together, with a team on the "A board" and another on the "B". These operators were almost always women until the early 1970s, when men were once again hired. Cord switchboards were often referred to as "cordboards" by telephone company personnel. Conversion to
321:
On the table or desk area in front of the operator are columns of 3-position toggle switches termed "keys", lamps, and cords. Each column consists of a front key and a rear key, a front lamp and a rear lamp, followed by a front cord and a rear cord, making up together a
164:
Following the invention of the telephone in 1876, the first telephones were rented in pairs which were limited to conversation between the parties operating those two instruments. The use of a central exchange was soon found to be even more advantageous than in
381:
area required special billing arrangements to allow the rate for a local call to vary based on the distance called. In less densely populated regions, calls from payphones were handled by normal assistance operators without the use of dedicated coin boards.
326:. The front key is the "talk" key allowing the operator to speak with that particular cord pair. The rear key on older "manual" boards and PBXs is used to ring a telephone physically. On newer boards, the back key is used to collect (retrieve) money from
313:
The switchboard is usually designed to accommodate the operator, who sits facing it. It has a high back panel, which consists of rows of female jacks, each jack designated and wired as a local extension of the switchboard (which serves an individual
226:
operator in order to place a toll call. In large cities, there was often a special number, such as 112, which would ring the long-distance operator directly. Elsewhere, the subscriber would ask the local operator to ring the long-distance operator.
214:
and other automated switching systems first eliminated the "B" operator and then, usually years later, the "A". Rural and suburban switchboards for the most part remained small and simple. In many cases, customers knew their operator by name.
251:
operator would dial the call. If the distant city did not have dialable numbers, the operator would dial the code for the inward operator serving the called party, and ask her to ring the number.
255:
phones required operator assistance. The operator was also available to help complete a local or long-distance number which did not complete. For example, if a customer encountered a
185:
as the first woman operator. Small towns typically had the switchboard installed in the operator's home so that he or she could answer calls on a 24-hour basis. In 1894,
274:
once provided on a cordboard (Toll
Stations, Mobile and Marine ). Operators from AT&T returned to work for the BOC as the intraLATA traffic was cut to the BOC.
222:) service, switchboards continued to serve specialized purposes. Before the advent of direct-dialed long-distance calls, a subscriber would need to contact the
64:
Nevertheless, many manual branch exchanges remained operational into the second half of the 20th century in many enterprises. Some establishments, such as the
824:
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companies to close smaller toll centers and consolidate operator services in regional centers which might be hundreds of miles from the subscriber.
107:
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369:, these "coin boards" were gradually phased out after the introduction of the Automated Coin Toll System that was provided by the
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Electronic devices and computer technology have given exchange operators more features. For example, a
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between users or other switchboards. The switchboard is an essential component of a manual
19:
8:
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839:
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482:
61:
in 1888, has replaced most switchboards in central telephone exchanges around the world.
50:
The switchboard saw the peak of its use in the 20th century before wider adoption of the
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1125:
1055:
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In May 1877, The Holmes
Burglar Alarm Company in Boston, Massachusetts, established by
40:
373:. Dedicated coin boards were primarily used in large, densely populated areas such as
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318:) or as an incoming or outgoing trunk line. The jack is also associated with a lamp.
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Cord switchboards used for these purposes were replaced in the 1970s and 1980s by
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Device used to connect telephone circuits to establish calls between users
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instead. Thus, on
September 1, 1878, Boston Telephone Dispatch hired
32:
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1005:
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327:
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76:
47:
who use electrical cords or switches to establish the connections.
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operator works a switchboard in the underground command post at
1475:
1435:
757:
361:
Some areas used specialized switchboards to handle calls from
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705:
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deal primarily with the United States and do not represent a
1402:
497:
Atlanta
Telephone History: Part 1 - Early Telephone Service
412:
The First
Telephone Switchboard and Its Method of Operation
414:, Bell Telephone Quarterly Volume 9(3), p.205 (July 1930).
492:. Vol. 26 (11th ed.). 1911. pp. 547–557.
338:
for testing, ringing and voice; and a sleeve wire for
449:"Telephone History: AT&T's First Male Operator"
1596:
246:In the 1940s, with the advent of dial pulse and
218:As telephone exchanges converted to automatic (
518:
104:The examples and perspective in this section
1533:Global telecommunications regulation bodies
187:New England Telephone and Telegraph Company
1569:
525:
511:
122:, or create a new section, as appropriate.
138:Learn how and when to remove this message
425:"PBS American Experience, The Telephone"
289:
233:
149:
79:usually has an attendant console, or an
31:is a device used to connect circuits of
18:
83:function, which bypasses the operator.
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532:
193:-operated switchboard on January 9 in
57:. The automatic exchange, invented by
506:
1579:
499:especially the section from 1905 on.
90:
13:
474:
417:
392:Telephone in United States history
14:
1621:
242:international switchboard in 1943
1578:
1568:
1559:
1558:
1547:
1168:Free-space optical communication
95:
371:Traffic Service Position System
264:Traffic Service Position System
68:, still operate a switchboard.
441:
404:
1:
1605:History of telecommunications
397:
155:
1554:Telecommunication portal
1335:Telecommunications equipment
285:
207:Divided Multiple Switchboard
55:automatic telephone exchange
7:
1071:Alexander Stepanovich Popov
385:
118:, discuss the issue on the
10:
1626:
775:Telecommunications history
410:G.K. Thompson, R.B. Hill,
86:
1542:
1484:
1421:
1383:Public Switched Telephone
1343:
1307:
1264:
1205:
1195:telecommunication circuit
1156:Fiber-optic communication
1139:
901:Francis Blake (telephone)
848:
696:Optical telecommunication
540:
1294:Orbital angular-momentum
731:Satellite communications
570:Communications satellite
195:Lexington, Massachusetts
1173:Molecular communication
996:Gardiner Greene Hubbard
825:Undersea telegraph line
560:Cable protection system
489:Encyclopædia Britannica
73:private branch exchange
1315:Communication protocol
1101:Charles Sumner Tainter
916:Walter Houser Brattain
861:Edwin Howard Armstrong
669:Information revolution
310:
243:
161:
24:
1289:Polarization-division
1021:Narinder Singh Kapany
986:Erna Schneider Hoover
906:Jagadish Chandra Bose
886:Alexander Graham Bell
617:online video platform
303:Offutt Air Force Base
299:Strategic Air Command
293:
278:within their region.
237:
153:
45:switchboard operators
43:, and is operated by
29:telephone switchboard
23:PBX switchboard, 1975
22:
1131:Vladimir K. Zworykin
1091:Almon Brown Strowger
1061:Charles Grafton Page
716:Prepaid mobile phone
644:Electrical telegraph
189:installed the first
154:Telephone operator,
116:improve this section
1610:Telephone exchanges
1081:Johann Philipp Reis
840:Wireless revolution
802:The Telephone Cases
659:Hydraulic telegraph
332:TRS phone connector
1279:Frequency-division
1256:Telephone exchange
1126:Charles Wheatstone
1056:Jun-ichi Nishizawa
1031:Innocenzo Manzetti
966:Reginald Fessenden
701:Optical telegraphy
534:Telecommunications
311:
244:
162:
41:telephone exchange
25:
1592:
1591:
1330:Store and forward
1325:Data transmission
1239:Network switching
1190:Transmission line
1036:Guglielmo Marconi
1001:Internet pioneers
866:Mohamed M. Atalla
835:Whistled language
483:"Telephone"
148:
147:
140:
52:electromechanical
1617:
1582:
1581:
1572:
1571:
1562:
1561:
1552:
1551:
1550:
1423:Notable networks
1413:Wireless network
1353:Cellular network
1345:Types of network
1320:Computer network
1207:Network topology
1121:Thomas A. Watson
976:Oliver Heaviside
961:Philo Farnsworth
936:Daniel Davis Jr.
911:Charles Bourseul
871:John Logie Baird
580:Data compression
575:Computer network
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455:. Archived from
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377:where the large
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1041:Robert Metcalfe
896:Tim Berners-Lee
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664:Information Age
536:
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475:Further reading
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453:PrivateLine.com
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328:coin telephones
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248:multi-frequency
203:Milo G. Kellogg
174:Edwin T. Holmes
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37:telephone calls
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1274:Space-division
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1111:Camille Tissot
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1086:Claude Shannon
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1076:Tivadar Puskás
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1046:Antonio Meucci
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891:Emile Berliner
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830:Videotelephony
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726:Radiotelephone
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301:headquarters,
295:U.S. Air Force
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201:of lines, and
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110:of the subject
108:worldwide view
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81:auto-attendant
59:Almon Strowger
15:
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1299:Code-division
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1284:Time-division
1282:
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1210:and switching
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1161:optical fiber
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1151:Coaxial cable
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1066:Radia Perlman
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956:Lee de Forest
954:
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951:Thomas Edison
949:
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941:Donald Davies
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937:
934:
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926:Claude Chappe
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1266:Multiplexing
1141:Transmission
1106:Nikola Tesla
1096:Henry Sutton
1051:Samuel Morse
981:Robert Hooke
946:Amos Dolbear
881:John Bardeen
800:
780:Telautograph
684:Mobile phone
639:Edholm's law
622:social media
555:Broadcasting
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461:. Retrieved
457:the original
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349:On a trunk,
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340:busy signals
336:tip and ring
324:cord circuit
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1466:NPL network
1178:Radio waves
1116:Alfred Vail
1026:Hedy Lamarr
1011:Dawon Kahng
971:Elisha Gray
931:Yogen Dalal
856:Nasir Ahmed
790:Teleprinter
654:Heliographs
240:Bell System
159: 1900
75:(PBX) in a
66:White House
1599:Categories
1512:Antarctica
1471:Toasternet
1393:Television
876:Paul Baran
808:Television
792:(teletype)
785:Telegraphy
763:transistor
741:Phryctoria
711:Photophone
689:Smartphone
679:Mass media
463:2013-09-18
434:2013-08-24
398:References
316:subscriber
167:telegraphy
33:telephones
1496:Americas
1485:Locations
1456:Internet2
1217:Bandwidth
921:Vint Cerf
818:streaming
796:Telephone
736:Semaphore
627:streaming
363:payphones
286:Operation
282:Florida.
183:Emma Nutt
128:June 2022
120:talk page
1564:Category
1451:Internet
1441:CYCLADES
1358:Ethernet
1308:Concepts
1232:terminal
1183:wireless
1006:Bob Kahn
849:Pioneers
674:Internet
565:Cable TV
386:See also
355:off-hook
309:in 1967.
307:Nebraska
238:A large
114:You may
77:business
1584:Commons
1574:Outline
1527:Oceania
1446:FidoNet
1431:ARPANET
1244:circuit
813:digital
542:History
429:PBS.org
351:on-hook
191:battery
87:History
1522:Europe
1492:Africa
1476:Usenet
1436:BITNET
1373:Mobile
1249:packet
758:MOSFET
753:device
550:Beacon
1505:South
1500:North
1461:JANET
1398:Telex
1388:Radio
1227:Nodes
1222:Links
1143:media
721:Radio
706:Pager
634:Drums
600:video
595:image
585:audio
365:. In
1517:Asia
1403:UUCP
1363:ISDN
353:and
220:dial
1408:WAN
1378:NGN
1368:LAN
649:Fax
590:DCT
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