| Technical characteristics of tones for the telephone service |
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This Recommendation sets the limits and recommended values of cadences, frequencies and levels for tones used in the telephone service. Those technical characteristics are relevant either for audible tones applied within the network or for those generated at the digital terminal equipment. |
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| Citation: |
https://handle.itu.int/11.1002/1000/4358 |
| Series title: |
E series: Overall network operation, telephone service, service operation and human factors E.100-E.229: International operation E.180-E.189: Tones in national signalling systems Q series: Switching and signalling, and associated measurements and tests Q.4-Q.59: International automatic and semi-automatic working Q.35-Q.39: Tones for use in national signalling systems |
| Approval date: |
1998-03-09 |
| Approval process: | TAP |
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Status: |
In force |
| Observation: | This Recommendation is published with the double number E.180 and Q.35 |
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Maintenance responsibility: |
ITU-T Study Group 21 |
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Further details: |
Patent statement(s)
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ITU-T Supplement
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Title
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Status
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Summary
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Table of contents
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Download
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E-100 series Suppl. 1 (02/2019)
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ITU-T E.100 series – Framework of disaster management for disaster relief system
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In force
|
here
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here
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here
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E Suppl. 11 (06/2020)
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Criteria for M2M/IoT-related assignments under Recommendation ITU-T E.164.1 and Recommendation ITU-T E.212 Annex A
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In force
|
here
|
here
|
here
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| Title |
Approved on |
Download |
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Radio fequency-level based single-number indicator for mobile network usefulness for a given range of applications
|
2023
|
here
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Technical Report on analysis of ITU-T F.930
|
2020
|
here
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Identify call location for emergency service
|
2020
|
here
|
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