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332:'s international subsidiary, first introduced dial tone as a standard facility with the cutover of the 7A Rotary Automatic Machine Switching System at Darlington, England, on 10 October 1914. Dial tone was an essential feature, because the 7A Rotary system was a common control switching system. It used the dial tone to indicate to the user that the switching system was ready to accept digits.
318:
system was ready to accept dialed digits. Each digit was transmitted as it was dialed which caused the switching system to select the desired destination circuit. Modern electronic telephones may store the digits as they are entered, and only switch off-hook to complete the dialing when the subscriber presses a button.
363:
tone that was amplitude-modulated at 120 Hz. Some dial tones were simply adapted from 60 Hz AC line current. In the UK, the standard Post Office dialing tone was 33 Hz; it was generated by a motor-driven ringing machine in most exchanges and by a vibrating-reed generator in the smaller
317:
when a subscriber picked up the telephone handset to make a call. The operator answered requesting the destination of the call. When manual exchanges were replaced with automated switching systems, the exchange generated a tone to the caller when the telephone set was picked up, indicating that the
339:
retired in 1961 it was nearly universal, but the president himself had never encountered a dial tone. When he picked up his own household phone, his assistant had to explain what the strange noise was, as well as show
Eisenhower how to use a
445:
A secondary dial tone is a dial tone-like sound presented to the caller after a call has been set up to prompt for additional digits to be dialed. Secondary dial tones are often used in call queuing and call forwarding systems.
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A soft dial tone or express dial tone may be used when no actual service is active on a line, and normal calls cannot be made. It is maintained only so that an attached phone can dial the
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of 90 Hz. The UK dial tone is similar, but combines 350 Hz and 450 Hz tones instead, creating a 100 Hz beat frequency. Most of
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407:, uses a constant single tone of 425 Hz. France currently uses a single 440 Hz tone and Japan uses a single 400 Hz tone.
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services do not generate dial tones as no connection is made until the entire number has been specified and transmitted.
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437:(PSTN), or it may be a different tone to remind users to dial a prefix or select by another method an outside line.
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A stutter dial tone is a rapidly interrupted tone used to indicate special service conditions. It may serve as a
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Before modern electronic telephone switching systems came into use, dial tones were usually generated by
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condition is detected. It indicates that the exchange is working and is ready to initiate a
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may also be accessed by technicians in order to facilitate installation or activation.
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In the United States, dial tone was introduced in the 1920s. By the time
President
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also play a dial tone to station users. It may be the same type as used by the
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Invented by engineer August
Kruckow, the dial tone was first used in 1908 in
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Listen to a dial tone from the United
Kingdom of 350 Hz + 450 Hz.
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ones. Some later ringing machines also generated a 50 Hz dial tone.
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Listen to a dial tone from North
America of 350 Hz + 440 Hz.
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The Bell
Telephone Manufacturing Company (BTMC) in Antwerp, Belgium,
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359:. In the United States, the standard "city" dial tone was a 600
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152:(PBX) to a terminating device, such as a telephone, when an
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391:(350 Hz and 440 Hz) which, when mixed, creates a
583:. Nps.gov – U.S. National Park Service. Archived from
367:The modern dial tone varies between countries. The
56:. Unsourced material may be challenged and removed.
652:
1855:
494:which owns or last leased the line, such as via
176:, requiring the caller to hang up and redial.
777:
638:
296:Listen to a Japanese dial tone of 400 Hz
254:Listen to a European dial tone of 425 Hz
1792:Global telecommunications regulation bodies
275:Listen to a French dial tone of 440 Hz
1828:
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770:
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116:Learn how and when to remove this message
16:Signal indicating that a call is possible
164:procedure is invoked, often eliciting a
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387:nations specifies a combination of two
313:Early telephone exchanges signaled the
240:Example of a current European dial tone
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198:Example of a North American dial tone
1838:
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54:adding citations to reliable sources
25:
581:"Eisenhower National Historic Site"
458:for voice mail, or indicate that a
421:
13:
552:Engber, Daniel (12 January 2014).
469:
304:Problems playing these files? See
186:
14:
1875:
435:public switched telephone network
219:Example of a UK/British dial tone
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1818:
1817:
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1427:Free-space optical communication
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19:For the G.I. Joe character, see
282:Example of a Japanese dial tone
41:needs additional citations for
654:Signaling (telecommunications)
573:
545:
1:
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373:North American Numbering Plan
261:Example of a French dial tone
1813:Telecommunication portal
1594:Telecommunications equipment
7:
1330:Alexander Stepanovich Popov
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10:
1880:
1034:Telecommunications history
554:"Who Made That Dial Tone?"
498:. Other functions such as
476:emergency telephone number
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18:
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1743:
1680:
1642:Public Switched Telephone
1602:
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1454:telecommunication circuit
1415:Fiber-optic communication
1398:
1160:Francis Blake (telephone)
1107:
955:Optical telecommunication
799:
743:
720:Multi-frequency signaling
715:Dual-tone multi-frequency
660:
456:message-waiting indicator
1553:Orbital angular-momentum
990:Satellite communications
829:Communications satellite
695:Special information tone
427:Private branch exchanges
166:special information tone
1432:Molecular communication
1255:Gardiner Greene Hubbard
1084:Undersea telegraph line
819:Cable protection system
735:Signalling System No. 7
730:Signalling System No. 6
606:"Dial Tone – Elmer Cat"
150:private branch exchange
1574:Communication protocol
1360:Charles Sumner Tainter
1175:Walter Houser Brattain
1120:Edwin Howard Armstrong
928:Information revolution
725:Signaling System No. 5
492:local exchange carrier
191:
1548:Polarization-division
1280:Narinder Singh Kapany
1245:Erna Schneider Hoover
1165:Jagadish Chandra Bose
1145:Alexander Graham Bell
876:online video platform
753:Telephones portal
587:on September 23, 2009
533:Telephones portal
431:key telephone systems
399:, as well as much of
190:
1390:Vladimir K. Zworykin
1350:Almon Brown Strowger
1320:Charles Grafton Page
975:Prepaid mobile phone
903:Electrical telegraph
466:has been activated.
337:Dwight D. Eisenhower
315:switchboard operator
50:improve this article
21:Dial Tone (G.I. Joe)
1340:Johann Philipp Reis
1099:Wireless revolution
1061:The Telephone Cases
918:Hydraulic telegraph
441:Secondary dial tone
1538:Frequency-division
1515:Telephone exchange
1385:Charles Wheatstone
1315:Jun-ichi Nishizawa
1290:Innocenzo Manzetti
1225:Reginald Fessenden
960:Optical telegraphy
793:Telecommunications
559:The New York Times
411:Cellular telephone
192:
172:, followed by the
146:telephone exchange
1864:Telephony signals
1851:
1850:
1589:Store and forward
1584:Data transmission
1498:Network switching
1449:Transmission line
1295:Guglielmo Marconi
1260:Internet pioneers
1125:Mohamed M. Atalla
1094:Whistled language
759:
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450:Stutter dial tone
369:Precise Tone Plan
349:electromechanical
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170:intercept message
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1682:Notable networks
1672:Wireless network
1612:Cellular network
1604:Types of network
1579:Computer network
1466:Network topology
1380:Thomas A. Watson
1235:Oliver Heaviside
1220:Philo Farnsworth
1195:Daniel Davis Jr.
1170:Charles Bourseul
1130:John Logie Baird
839:Data compression
834:Computer network
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351:devices such as
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460:calling feature
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1007:Semiconductor
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911:
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869:
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866:Digital media
864:
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700:Off-hook tone
698:
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548:
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516:Ringback tone
514:
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497:
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477:
467:
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447:
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408:
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401:Latin America
398:
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283:
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199:
177:
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174:off-hook tone
171:
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155:
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143:
139:
135:
134:dialling tone
131:
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109:
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81:
77:
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70:
67: –
66:
62:
61:Find sources:
55:
51:
45:
44:
39:This article
37:
33:
28:
27:
22:
1525:Multiplexing
1400:Transmission
1365:Nikola Tesla
1355:Henry Sutton
1310:Samuel Morse
1240:Robert Hooke
1205:Amos Dolbear
1140:John Bardeen
1059:
1039:Telautograph
943:Mobile phone
898:Edholm's law
881:social media
814:Broadcasting
685:Reorder tone
675:Ringing tone
664:
609:. Retrieved
600:
589:. Retrieved
585:the original
575:
563:. Retrieved
557:
547:
473:
453:
444:
425:
409:
366:
346:
334:
327:
320:
312:
303:
162:partial dial
133:
129:
127:
112:
103:
93:
86:
79:
72:
60:
48:Please help
43:verification
40:
1725:NPL network
1437:Radio waves
1375:Alfred Vail
1285:Hedy Lamarr
1270:Dawon Kahng
1230:Elisha Gray
1190:Yogen Dalal
1115:Nasir Ahmed
1049:Teleprinter
913:Heliographs
680:Busy signal
521:Busy signal
342:rotary dial
325:, Germany.
106:August 2007
65:"Dial tone"
1771:Antarctica
1730:Toasternet
1652:Television
1135:Paul Baran
1067:Television
1051:(teletype)
1044:Telegraphy
1022:transistor
1000:Phryctoria
970:Photophone
948:Smartphone
938:Mass media
611:11 January
591:2010-09-06
565:10 January
539:References
462:, such as
429:(PBXs) or
323:Hildesheim
306:media help
144:sent by a
76:newspapers
1755:Americas
1744:Locations
1715:Internet2
1476:Bandwidth
1180:Vint Cerf
1077:streaming
1055:Telephone
995:Semaphore
886:streaming
665:Dial tone
478:(such as
385:Caribbean
357:vibrators
130:dial tone
1858:Category
1823:Category
1710:Internet
1700:CYCLADES
1617:Ethernet
1567:Concepts
1491:terminal
1442:wireless
1265:Bob Kahn
1108:Pioneers
933:Internet
824:Cable TV
705:Zip tone
670:Ringtone
510:See also
500:ringback
417:Variants
371:for the
154:off-hook
1843:Commons
1833:Outline
1786:Oceania
1705:FidoNet
1690:ARPANET
1503:circuit
1072:digital
801:History
710:2600 Hz
375:of the
344:phone.
180:History
168:and an
140:) is a
136:in the
90:scholar
1781:Europe
1751:Africa
1735:Usenet
1695:BITNET
1632:Mobile
1508:packet
1017:MOSFET
1012:device
809:Beacon
405:Africa
397:Europe
381:Canada
92:
85:
78:
71:
63:
1764:South
1759:North
1720:JANET
1657:Telex
1647:Radio
1486:Nodes
1481:Links
1402:media
980:Radio
965:Pager
893:Drums
859:video
854:image
844:audio
496:6-1-1
389:tones
97:JSTOR
83:books
1776:Asia
1662:UUCP
1622:ISDN
613:2021
567:2014
504:ANAC
403:and
69:news
1667:WAN
1637:NGN
1627:LAN
908:Fax
849:DCT
502:or
488:999
486:or
484:112
480:911
355:or
148:or
52:by
1860::
556:.
482:,
379:,
377:US
361:Hz
138:UK
128:A
1794:)
1790:(
785:e
778:t
771:v
646:e
639:t
632:v
615:.
594:.
569:.
308:.
132:(
119:)
113:(
108:)
104:(
94:·
87:·
80:·
73:·
46:.
23:.
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