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343:'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.
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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.
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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
328:
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
350:
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
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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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services do not generate dial tones as no connection is made until the entire number has been specified and transmitted.
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448:(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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370:. In the United States, the standard "city" dial tone was a 600
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163:(PBX) to a terminating device, such as a telephone, when an
402:(350 Hz and 440 Hz) which, when mixed, creates a
594:. Nps.gov – U.S. National Park Service. Archived from
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378:The modern dial tone varies between countries. The
67:. Unsourced material may be challenged and removed.
505:which owns or last leased the line, such as via
187:, requiring the caller to hang up and redial.
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307:Listen to a Japanese dial tone of 400 Hz
265:Listen to a European dial tone of 425 Hz
8:
1798:Global telecommunications regulation bodies
286:Listen to a French dial tone of 440 Hz
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127:Learn how and when to remove this message
27:Signal indicating that a call is possible
175:procedure is invoked, often eliciting a
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398:nations specifies a combination of two
324:Early telephone exchanges signaled the
251:Example of a current European dial tone
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209:Example of a North American dial tone
7:
1844:
65:adding citations to reliable sources
592:"Eisenhower National Historic Site"
469:for voice mail, or indicate that a
563:Engber, Daniel (12 January 2014).
315:Problems playing these files? See
25:
446:public switched telephone network
230:Example of a UK/British dial tone
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1433:Free-space optical communication
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30:For the G.I. Joe character, see
293:Example of a Japanese dial tone
52:needs additional citations for
665:Signaling (telecommunications)
1:
384:North American Numbering Plan
272:Example of a French dial tone
1819:Telecommunication portal
1600:Telecommunications equipment
1336:Alexander Stepanovich Popov
1886:
1040:Telecommunications history
565:"Who Made That Dial Tone?"
509:. Other functions such as
487:emergency telephone number
29:
1807:
1648:Public Switched Telephone
1460:telecommunication circuit
1421:Fiber-optic communication
1166:Francis Blake (telephone)
961:Optical telecommunication
749:
731:Multi-frequency signaling
726:Dual-tone multi-frequency
671:
467:message-waiting indicator
1559:Orbital angular-momentum
996:Satellite communications
835:Communications satellite
706:Special information tone
438:Private branch exchanges
177:special information tone
1438:Molecular communication
1261:Gardiner Greene Hubbard
1090:Undersea telegraph line
825:Cable protection system
741:Signalling System No. 7
617:"Dial Tone – Elmer Cat"
161:private branch exchange
1580:Communication protocol
1366:Charles Sumner Tainter
1181:Walter Houser Brattain
1126:Edwin Howard Armstrong
934:Information revolution
736:Signaling System No. 5
503:local exchange carrier
202:
1554:Polarization-division
1286:Narinder Singh Kapany
1251:Erna Schneider Hoover
1171:Jagadish Chandra Bose
1151:Alexander Graham Bell
882:online video platform
759:Telephones portal
598:on September 23, 2009
544:Telephones portal
442:key telephone systems
410:, as well as much of
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1396:Vladimir K. Zworykin
1356:Almon Brown Strowger
1326:Charles Grafton Page
981:Prepaid mobile phone
909:Electrical telegraph
477:has been activated.
348:Dwight D. Eisenhower
326:switchboard operator
61:improve this article
32:Dial Tone (G.I. Joe)
1346:Johann Philipp Reis
1105:Wireless revolution
1067:The Telephone Cases
924:Hydraulic telegraph
452:Secondary dial tone
1544:Frequency-division
1521:Telephone exchange
1391:Charles Wheatstone
1321:Jun-ichi Nishizawa
1296:Innocenzo Manzetti
1231:Reginald Fessenden
966:Optical telegraphy
799:Telecommunications
570:The New York Times
422:Cellular telephone
203:
183:, followed by the
157:telephone exchange
1870:Telephony signals
1857:
1856:
1595:Store and forward
1590:Data transmission
1504:Network switching
1455:Transmission line
1301:Guglielmo Marconi
1266:Internet pioneers
1131:Mohamed M. Atalla
1100:Whistled language
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461:Stutter dial tone
380:Precise Tone Plan
360:electromechanical
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1688:Notable networks
1678:Wireless network
1618:Cellular network
1610:Types of network
1585:Computer network
1472:Network topology
1386:Thomas A. Watson
1241:Oliver Heaviside
1226:Philo Farnsworth
1201:Daniel Davis Jr.
1176:Charles Bourseul
1136:John Logie Baird
845:Data compression
840:Computer network
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471:calling feature
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1549:Time-division
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927:
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922:
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917:
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905:
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872:Digital media
870:
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848:
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748:
742:
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734:
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729:
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719:
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712:
711:Off-hook tone
709:
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679:
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587:
584:
572:
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527:Ringback tone
525:
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512:
508:
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419:
417:
413:
412:Latin America
409:
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401:
397:
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389:
385:
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210:
190:
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186:
185:off-hook tone
182:
178:
174:
170:
166:
162:
158:
154:
150:
146:
145:dialling tone
142:
131:
128:
120:
109:
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99:
95:
92:
88:
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81:
78: –
77:
73:
72:Find sources:
66:
62:
56:
55:
50:This article
48:
44:
39:
38:
33:
19:
1531:Multiplexing
1406:Transmission
1371:Nikola Tesla
1361:Henry Sutton
1316:Samuel Morse
1246:Robert Hooke
1211:Amos Dolbear
1146:John Bardeen
1065:
1045:Telautograph
949:Mobile phone
904:Edholm's law
887:social media
820:Broadcasting
696:Reorder tone
686:Ringing tone
675:
620:. Retrieved
611:
600:. Retrieved
596:the original
586:
574:. Retrieved
568:
558:
484:
464:
455:
436:
420:
377:
357:
345:
338:
331:
323:
173:partial dial
144:
140:
138:
123:
114:
104:
97:
90:
83:
71:
59:Please help
54:verification
51:
1731:NPL network
1443:Radio waves
1381:Alfred Vail
1291:Hedy Lamarr
1276:Dawon Kahng
1236:Elisha Gray
1196:Yogen Dalal
1121:Nasir Ahmed
1055:Teleprinter
919:Heliographs
691:Busy signal
532:Busy signal
353:rotary dial
336:, Germany.
117:August 2007
76:"Dial tone"
1777:Antarctica
1736:Toasternet
1658:Television
1141:Paul Baran
1073:Television
1057:(teletype)
1050:Telegraphy
1028:transistor
1006:Phryctoria
976:Photophone
954:Smartphone
944:Mass media
622:11 January
602:2010-09-06
576:10 January
550:References
473:, such as
440:(PBXs) or
334:Hildesheim
317:media help
155:sent by a
87:newspapers
1761:Americas
1750:Locations
1721:Internet2
1482:Bandwidth
1186:Vint Cerf
1083:streaming
1061:Telephone
1001:Semaphore
892:streaming
676:Dial tone
489:(such as
396:Caribbean
368:vibrators
141:dial tone
1864:Category
1829:Category
1716:Internet
1706:CYCLADES
1623:Ethernet
1573:Concepts
1497:terminal
1448:wireless
1271:Bob Kahn
1114:Pioneers
939:Internet
830:Cable TV
716:Zip tone
681:Ringtone
521:See also
511:ringback
428:Variants
382:for the
165:off-hook
18:Dialtone
1849:Commons
1839:Outline
1792:Oceania
1711:FidoNet
1696:ARPANET
1509:circuit
1078:digital
807:History
721:2600 Hz
386:of the
355:phone.
191:History
179:and an
151:) is a
147:in the
101:scholar
1787:Europe
1757:Africa
1741:Usenet
1701:BITNET
1638:Mobile
1514:packet
1023:MOSFET
1018:device
815:Beacon
416:Africa
408:Europe
392:Canada
103:
96:
89:
82:
74:
1770:South
1765:North
1726:JANET
1663:Telex
1653:Radio
1492:Nodes
1487:Links
1408:media
986:Radio
971:Pager
899:Drums
865:video
860:image
850:audio
507:6-1-1
400:tones
108:JSTOR
94:books
1782:Asia
1668:UUCP
1628:ISDN
624:2021
578:2014
515:ANAC
414:and
80:news
1673:WAN
1643:NGN
1633:LAN
914:Fax
855:DCT
513:or
499:999
497:or
495:112
491:911
366:or
159:or
63:by
1866::
567:.
493:,
390:,
388:US
372:Hz
149:UK
139:A
1800:)
1796:(
791:e
784:t
777:v
657:e
650:t
643:v
626:.
605:.
580:.
319:.
143:(
130:)
124:(
119:)
115:(
105:·
98:·
91:·
84:·
57:.
34:.
20:)
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