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Telephone line tone specification

Discussion in 'Electronic Design' started by eeh, Dec 12, 2005.

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  1. eeh

    eeh Guest


    Do anyone know where I can find the telephone line tone specifications
    about the ringing tone/interval and busy tone/interval in different
    countries such as US and England and France and Germany and Japan?

    Do it has some standards such as IEEE spec or else?

  2. Guest

    These tones are defined by the local telecommunications regulatory
    authority; Austel, FCC, etc. There is no one international standards
  3. Alan

    Alan Guest

    The ITU used to publish the information in their documents

  4. Don Bowey

    Don Bowey Guest

    In the USA and Canada, there were so many tones used in so many ways in
    different types of switching machines that it wasn't realistic to create a
    Standard for them, so the tones and methods were placed in an Appendix of
    ANSI T1.401-1993, which has probably been updated a few times by now. An
    Appendix is used to convey information, but it contains no requirements.
    ANSI T1.401 is the Standard for the interface between Carriers and their
    customers for Loop-Start and Ground-Start signaling (basically, think POTS).
    All of this work was harmonized with Canada's CSA, by our illustrious
    Chairman, who was Canadian.

    Special Information Tones (SIT) and the related messages, is contained in
    ANSI T1.209.

  5. theJackal

    theJackal Guest

    Regarding the 2 CCTIT systems I'm familiar with here are the values
    which should correspond to those in the US

    CCTIT No.3 CCTIT No.4
    Busy tone 2280Hz +OR- 6Hz 2040Hz,2400Hz, 150+or-30 ms
    600ms + OR -120ms 2040+OR-6Hz,


    Ring 2280Hz +OR- 6Hz 2040Hz,2400Hz, 150+or-30 ms
    150ms + OR -30ms 2040+OR-6Hz, 100+OR-20ms
    Silence 100+OR-20ms 2040+OR-6Hz, 100+OR-20ms
    2280Hz +OR- 6Hz
    150ms + OR -30ms
  6. Don Bowey

    Don Bowey Guest

    None of those agree with the tones used in the US, which are all below 1kHz.

  7. Alan

    Alan Guest

    Those are all "inter-equipment" tones used for long distance
    signalling. The UK used to use 2280 extensively many years ago while
    the 2040/2400 tones were used for signalling between countries in

    The UK 2280 system used "decadic" dialling (ie 1 to 10 pulses) for
    dialling the numbers with various other tone lengths for control
    signals (ie call answer).

    The 2040/2400 system was basically a four bit binary with one tone
    representin 0 and the other representin 1. The number was sent as a
    series of four tones. This gave a total of 16 possible combinations
    some of which were used for control.

  8. theJackal

    theJackal Guest

    Thats why I indicated that they are CCITT codes which is also known as
    the International Telecommunications Union.
    CCITT = International Telecommunications Union
    Not only used for international traffic but also for submarine
    communications, land based cable and microwave links.
    Ummmm ...You claim? So what do they use now? That is what the Op is
    asking and no one has given him an answer till I wrote .
    It will work just as well as with a multifrquency dial phone if you
    connect up a 1 to 10 pulse dialling phone there.
    I can see you are confusing dialing modes/frequencies with busy tone
    and ringing frequencies. Now ...
    CCITT specs give 2 seperate frequencies ranging from 700Hz to
    1500Hz) summed together to send a single number. Now a third tone is
    also used but ... i think i've said enough.

    "Go easy with the whisky"

  9. theJackal

    theJackal Guest

    WRONG! Try getting a C1 line on a type 2002 channel. You can go upto

    "Go easy on the whisky"

  10. Alan

    Alan Guest

    But I already gave the OP a link to :

    where there is a pretty comprehensive list of the tones a telephone
    subscriber would hear, not the tones which are used inter-equipment.

  11. Don Bowey

    Don Bowey Guest

    Your comments are not relevant. It's unfortunate you did not observe that
    the OP was NOT asking about interoffice signaling.
  12. theJackal

    theJackal Guest

    Oops sorry I missed that. Valuable site and nice information .

    "Go easy on the whisky"

  13. Don Bowey

    Don Bowey Guest

    Learn to read. Your comments are not relevant to the subject.
  14. theJackal

    theJackal Guest

    Watch TV it will educate you more

    "If you believe everything you read, better not read."
    "Go easy on the whisky "

  15. theJackal

    theJackal Guest

    ha ha the great instructor has spoken.

    Most men are within a finger's breadth of being mad.


    "Go easy with the whisky"

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