1785:
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1198:
1091:
975:
829:
594:
455:
257:
49:
1849:," to place long-distance calls, without using the network's user facilities, that would be billed to another number or dismissed entirely by the telecom company's billing system as an incomplete call. A number of similar "color boxes" were also created to control other aspects of the phone network. (
1689:, thus fooling the system into completing free calls. In the United States, a nickel is represented by one tone, a dime by two, and a quarter by a set of five. Any device capable of playing back recorded sounds can potentially be used as a red box. Commonly used devices include modified
693:
1476:-related phone calls a household receives by imitating the tone signal normally played by a phone company to indicate a line has been disconnected. The Telezapper was created by Privacy Technologies, Inc, a wholly owned subsidiary of Royal Appliance Mfg. Co. (
655:
276:
694:
994:
338:
685:
1844:
were commonplace and could be significant, depending on the time, duration and destination of the call. A blue box device allowed for circumventing these charges by enabling an illicit user, referred to as a
339:
1840:
tones formerly used within the North
American long-distance telephone network to send line status and called number information over voice circuits. During that period, charges associated with
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868:
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1725:
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654:
109:
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633:
695:
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352:
1744:
in telephony is a tone provided to the remaining party to a call after the remote party hangs up. Typically, the disconnect tone is a few cycles of the
867:
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40:
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100:
66:
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1336:
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1273:
1215:
266:
1809:
These multi-frequency tones were generated by automated switching equipment. The blue box was designed to replicate these tones.
1723:
1652:
1109:
1223:
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472:
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407:
189:
79:
1752:, or the off-hook tone (e.g. in US), or between five and fifteen seconds of the Number Unobtainable tone (e.g. in UK). (
1035:
765:
1726:
1154:
707:
667:
603:
415:
1394:
1370:
942:(PSTN) that is returned to a calling party to indicate that the call cannot be processed through the network. (
213:
1598:, and sometimes the time, of the last caller. The service may also offer the facility to place a call to the
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197:
1644:
880:
121:
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1047:
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838:
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58:
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781:
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is alerting the receiving party. The tone is typically a repeated cadence similar to a traditional
486:
1385:
403:
193:
1837:
1584:
1389:
757:
217:
208:. The tone stops when the first dialed digit is recognized. If no digits are forthcoming, the
17:
1604:
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1534:
1256:
1100:
546:
209:
204:
condition is detected. It indicates that the exchange is working and is ready to initiate a
1754:
1740:
1518:
1434:
1307:
1286:
1231:
776:), but is usually not played synchronously. Various telecommunication groups, such as the
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558:
419:
205:
185:
1599:
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1388:
consisting of three rising tones indicating a call has failed. It usually precedes a
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supplied to telephone customers, starting in 1963. DTMF is standardized as
1031:
550:
503:
399:
226:
176:
94:
Listen to a dial tone from the United
Kingdom of 350 Hz + 450 Hz.
796:
technology ringing tone can be customized and even used for advertising. (
1851:
1828:
1693:
tone dialers, personal MP3 players, and audio-recording greeting cards. (
1248:
554:
201:
1576:
1379:
73:
Listen to a dial tone from North
America of 350 Hz + 440 Hz.
1030:
system using the voice-frequency band over telephone lines between
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502:
Some central office switches in the United States, notably older
1538:
1060:
1022:
618:
A ringing tone from the United
Kingdom, Ireland, and New Zealand
506:
systems, utilize a single frequency tone, 480 Hz, known as
1731:
557:
without use for an extended period, effectively disabling the
303:
Listen to a busy signal from North
America used prior to 1980.
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1507:
1423:
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1089:
973:
827:
592:
453:
255:
200:(PBX) to a terminating device, such as a telephone, when an
47:
1685:
device that generates tones to simulate inserting coins in
1519:
Example of Last-call return from
Verizon Home Phone Service
1042:
in the United States, and became known under the trademark
510:
for this purpose. Listen to an older 480Hz off-hook tone.
1763:
1704:
1613:
1487:
1449:
Intercept tone played by The TeleZapper (plays 2 times)
1403:
1176:
1069:
953:
807:
572:
433:
235:
27:
784:(GPO) developed standards, in part taken over by the
1054:Recommendation Q.23. It is also known in the UK as
1594:to subscribers to provide the subscriber with the
895:Listen to a reorder tone from the United Kingdom.
414:that indicates failure to complete the requested
367:Listen to a busy signal from the United Kingdom.
1034:equipment and other communications devices and
788:(ETSI) and other standards bodies. With modern
786:European Telecommunications Standards Institute
224:, requiring the caller to hang up and redial. (
1734:phone disconnect tone (not the original audio)
480:Listen to an off-hook tone from North America.
1472:is a device designed to reduce the number of
157:Listen to a Japanese dial tone of 400 Hz
115:Listen to a European dial tone of 425 Hz
8:
853:Listen to a reorder tone from North America.
289:Example of an old North American busy signal
282:Listen to a busy signal from North America.
136:Listen to a French dial tone of 440 Hz
1836:that produces tones used to generate the
661:A European ringing tone per ETSI standard
465:Example of a North American Off-hook tone
938:is an audible call progress tone in the
839:Example of a North American reorder tone
604:UK, Ireland, and NZ audible ringing tone
212:procedure is invoked, often eliciting a
722:Audible ringing tone from North America
353:Example of a United Kingdom busy signal
346:Listen to a busy signal from the France
267:Example of a North American busy signal
101:Example of a current European dial tone
1816:
1665:
1552:
1456:
1354:
1126:
1007:
902:
729:
517:
374:
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1153:(cycles per second) that was used in
874:Listen to a reorder tone from Europe.
760:that is heard by the originator of a
59:Example of a North American dial tone
7:
1777:Portal:Telephones/Selected audio/13
1718:Portal:Telephones/Selected audio/12
1627:Portal:Telephones/Selected audio/11
1501:Portal:Telephones/Selected audio/10
324:Listen to a busy signal from Europe.
1417:Portal:Telephones/Selected audio/9
1190:Portal:Telephones/Selected audio/8
1083:Portal:Telephones/Selected audio/7
1018:Dual-tone multi-frequency signaling
967:Portal:Telephones/Selected audio/6
821:Portal:Telephones/Selected audio/5
586:Portal:Telephones/Selected audio/4
447:Portal:Telephones/Selected audio/3
249:Portal:Telephones/Selected audio/2
41:Portal:Telephones/Selected audio/1
1355:Problems playing these files? See
1038:. DTMF was first developed in the
903:Problems playing these files? See
860:Example of a European reorder tone
730:Problems playing these files? See
518:Problems playing these files? See
375:Problems playing these files? See
165:Problems playing these files? See
24:
1541:number, 987-654-3210), voiced by
940:public switched telephone network
881:Example of a British reorder tone
310:Example of a European busy signal
80:Example of a UK/British dial tone
1817:Problems playing this file? See
1799:
1666:Problems playing this file? See
1649:
1553:Problems playing this file? See
1523:
1457:Problems playing this file? See
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1127:Problems playing this file? See
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1008:Problems playing this file? See
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331:Example of a French busy signal
143:Example of a Japanese dial tone
1000:audio output of a DTMF signal.
639:Australia audible ringing tone
1:
549:for alerting a user that the
122:Example of a French dial tone
1155:telecommunication signaling
1028:telecommunication signaling
708:North American ringing tone
1870:
1658:The .25 USD tone sequence.
1392:describing the problem. (
1161:telephone networks using
1371:special information tone
214:special information tone
1795:Multi-frequency dialing
625:Australian ringing tone
198:private branch exchange
1788:
1735:
1638:
1512:
1428:
1383:international standard
1280:No Circuit – intraLATA
1201:
1094:
1048:push-button telephones
978:
832:
764:while the destination
597:
458:
260:
52:
1842:long-distance calling
1787:
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1427:
1390:recorded announcement
1200:
1115:A 2600 Hz tone (
1093:
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831:
701:A French ringing tone
668:Japanese ringing tone
646:European ringing tone
596:
457:
259:
51:
1157:in mid-20th century
918:, also known as the
770:power ringing signal
1730:Reproduction of an
1645:USA Red Boxing Tone
1587:feature offered by
782:General Post Office
686:French ringing tone
418:of that particular
1789:
1736:
1639:
1513:
1429:
1386:call progress tone
1202:
1095:
979:
833:
598:
459:
404:call-progress tone
261:
220:, followed by the
194:telephone exchange
53:
1838:in-band signaling
1834:electronic device
1804:
1771:Selected audio 13
1727:
1712:Selected audio 12
1653:
1621:Selected audio 11
1592:service providers
1585:telecommunication
1528:
1495:Selected audio 10
1444:
1338:
1322:Ineffective/Other
1317:
1296:
1275:
1241:
1217:
1110:
1036:switching centers
995:
890:
869:
848:
758:telecommunication
717:
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218:intercept message
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18:Portal:Telephones
1861:
1806:
1805:
1786:
1766:
1728:
1707:
1655:
1654:
1636:
1616:
1596:telephone number
1569:automatic recall
1564:Last-call return
1535:last-call return
1530:
1529:
1510:
1490:
1446:
1445:
1426:
1411:Selected audio 9
1406:
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1184:Selected audio 8
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547:telephony signal
535:off-hook warning
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441:Selected audio 3
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190:telephony signal
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35:Selected audio 1
30:
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1741:disconnect tone
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1222:Reorder – intra
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1168:Full article...
1163:carrier systems
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945:Full article...
928:all trunks busy
924:congestion tone
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746:audible ringing
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920:fast busy tone
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762:telephone call
754:signaling tone
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559:telephone line
553:has been left
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420:telephone call
402:is an audible
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206:telephone call
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1600:calling party
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1537:(with a fake
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1474:telemarketing
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1139:
1132:
1130:
1118:
1102:
1085:
1084:
1076:
1073:
1065:
1063:
1062:
1057:
1053:
1049:
1045:
1041:
1037:
1033:
1029:
1025:
1024:
1019:
1013:
1011:
986:
969:
968:
960:
957:
949:
947:
946:
941:
937:
933:
929:
925:
921:
917:
916:
908:
906:
882:
861:
840:
823:
822:
814:
811:
803:
801:
800:
795:
791:
787:
783:
779:
775:
771:
767:
763:
759:
755:
751:
750:ringback tone
747:
743:
742:
735:
733:
709:
687:
669:
647:
626:
605:
588:
587:
579:
576:
568:
566:
565:
560:
556:
552:
548:
544:
540:
539:howling tone,
536:
532:
531:
530:off-hook tone
523:
521:
509:
505:
488:
466:
449:
448:
440:
437:
429:
427:
426:
421:
417:
413:
412:calling party
409:
405:
401:
397:
393:
389:
388:
380:
378:
354:
332:
311:
290:
268:
251:
250:
242:
239:
231:
229:
228:
223:
222:off-hook tone
219:
215:
211:
207:
203:
199:
195:
191:
187:
183:
182:dialling tone
179:
178:
170:
168:
144:
123:
102:
81:
60:
43:
42:
34:
31:
19:
1850:
1827:
1825:
1775:
1753:
1739:
1737:
1716:
1694:
1676:
1674:
1625:
1603:
1580:
1568:
1562:
1561:
1499:
1477:
1467:
1465:
1415:
1393:
1375:
1369:
1363:
1344:
1343:Future Use (
1246:
1188:
1166:
1143:2600 Hz
1142:
1136:
1135:
1116:
1081:
1059:
1055:
1043:
1021:
1017:
1016:
985:DTMF dialing
965:
943:
935:
931:
927:
923:
919:
915:reorder tone
913:
911:
819:
797:
773:
749:
745:
741:Ringing tone
739:
738:
584:
562:
542:
538:
534:
528:
526:
507:
445:
423:
396:engaged tone
395:
391:
385:
383:
247:
225:
210:partial dial
181:
175:
173:
39:
1691:Radio Shack
1247:Unassigned
1046:for use in
1040:Bell System
778:Bell System
543:howler tone
406:or audible
387:busy signal
1819:media help
1687:pay phones
1668:media help
1555:media help
1533:Listen to
1469:TeleZapper
1459:media help
1357:media help
1329:Future SIT
1253:CLASS code
1138:2600 hertz
1129:media help
1044:Touch-Tone
1010:media help
905:media help
794:smartphone
790:cell phone
732:media help
520:media help
416:connection
377:media help
192:sent by a
167:media help
1683:phreaking
1589:telephony
1579:service)
1571:, or (on
1543:Pat Fleet
1366:telephony
1301:Intercept
1147:frequency
1032:telephone
922:, or the
551:telephone
508:High Tone
504:GTD-5 EAX
487:High Tone
400:telephony
392:busy tone
177:dial tone
1847:phreaker
1829:blue box
1378:) is an
1345:Not Used
1249:N11 code
780:and the
774:ringtone
766:terminal
555:off-hook
202:off-hook
1746:reorder
1678:red box
1583:, is a
1581:camp-on
1577:centrex
1380:in-band
1266:NC' SIT
1208:RO' SIT
1145:) is a
1101:2600 Hz
1026:) is a
752:) is a
748:, also
545:) is a
410:to the
216:and an
188:) is a
184:in the
1832:is an
1768:
1709:
1618:
1492:
1435:IC SIT
1408:
1308:IO SIT
1287:IC SIT
1257:prefix
1232:VC SIT
1181:
1074:
958:
812:
577:
533:(also
438:
408:signal
240:
32:
1681:is a
1151:hertz
1052:ITU-T
926:, or
398:) in
16:<
1765:edit
1750:busy
1706:edit
1615:edit
1575:and
1539:NANP
1489:edit
1466:The
1405:edit
1368:, a
1224:LATA
1178:edit
1117:LOUD
1071:edit
1023:DTMF
955:edit
936:tone
912:The
809:edit
792:and
574:edit
527:The
435:edit
390:(or
237:edit
29:edit
1732:IOS
1602:. (
1573:PBX
1376:SIT
1364:In
1255:or
1165:. (
1149:in
1058:. (
1056:MF4
932:ATB
756:in
561:. (
541:or
422:. (
394:or
196:or
1855:)
1826:A
1758:)
1748:,
1738:A
1699:)
1675:A
1608:)
1567:,
1482:)
1398:)
1251:,
1171:)
1064:)
948:)
934:)
802:)
567:)
537:,
428:)
384:A
230:)
186:UK
174:A
1845:"
1821:.
1670:.
1557:.
1545:.
1461:.
1374:(
1359:.
1347:)
1141:(
1131:.
1119:)
1020:(
1012:.
930:(
907:.
772:(
744:(
734:.
522:.
379:.
180:(
169:.
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