Precise Tone Plan

Precise Tone Plan

The Precise Tone Plan specification for the North American network defines the Call-progress tones used for standard signaling in the PSTN. The tones are as follows:

* dial tone is a continuous tone having frequencies of 350 and 440 Hz at a level of −13 dBm

* ringback tone is defined as comprising frequencies of 440 and 480 Hz at a level of −19 dBm and a cadence of 2 seconds ON and 4 seconds OFF

* busy tone is defined as having frequency components of 480 and 620 Hz at a level of −24 dBm and a cadence of half a second ON and half a second OFF

* reorder tone, also called "fast busy" tone, contains the same frequency components as busy tone at a similar level but with a cadence of 0.25 of a second ON and 0.25 of a second OFF

Prior to the Precise Tone Plan, devices used other frequencies and levels. Such tones generated by older telephone exchange equipment did not follow the Precise Tone Plan and were either formed as dual frequency tones or equivalently as ring modulated signals where a higher frequency is modulated by a lower frequency.


Wikimedia Foundation. 2010.

Игры ⚽ Поможем написать курсовую

Look at other dictionaries:

  • North American Precise Tone Plan —    (NAPTP)    The standard method of registering call progress tones …   IT glossary of terms, acronyms and abbreviations

  • Dual-tone multi-frequency signaling — One of the few production telephone DTMF keypads with all 16 keys, from an Autovon Telephone. The column of red keys produces the A, B, C, and D DTMF events. Dual tone multi frequency signaling (DTMF) is used for telecommunication signaling over… …   Wikipedia

  • Dial tone — For the G.I. Joe character, see Dial Tone (G.I. Joe). A dial tone (known in the British Isles as a dialling tone)[1] is a telephony signal used to indicate that the telephone exchange is working, has recognized an off hook, and is ready to accept …   Wikipedia

  • Dual-tone multi-frequency — (DTMF) signaling is used for telephone signaling over the line in the voice frequency band to the call switching center. The version of DTMF used for telephone tone dialing is known by the trademarked term Touch Tone (canceled March 13, 1984),… …   Wikipedia

  • S-Plan — The S Plan or Sabotage Campaign or England Campaign was a campaign of bombing and sabotage against the civil, economic, and military infrastructure of Britain from 1939 to 1940. The campaign was conducted by members of the Irish Republican Army… …   Wikipedia

  • Tonalité d'invitation — à numéroter Des problèmes pour écouter le fichier ? Aidez moi La tonalité d invitation à numéroter, ou plus simplement tonalité d invitation, encore appelée tonalité de manœuvre, est un signal sonore émis par le commutateur sur une ligne… …   Wikipédia en Français

  • Tonalité d'invitation à numéroter — Fichier audio Tonalité d invitation française (info) …   Wikipédia en Français

  • Tonalité de manœuvre — Tonalité d invitation à numéroter Des problèmes pour écouter le fichier ? Aidez moi La tonalité d invitation à numéroter, ou plus simplement tonalité d invitation, encore appelée tonalité de manœuvre, est un signal sonore émis par le… …   Wikipédia en Français

  • NAPTP —    See North American Precise Tone Plan …   IT glossary of terms, acronyms and abbreviations

  • arts, East Asian — Introduction       music and visual and performing arts of China, Korea, and Japan. The literatures of these countries are covered in the articles Chinese literature, Korean literature, and Japanese literature.       Some studies of East Asia… …   Universalium

Share the article and excerpts

Direct link
… Do a right-click on the link above
and select “Copy Link”