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Article #14651Re: Tone frequencies on telephone
From: Scott Fraser
Date: Tue, 17 Nov 1992 20:35
Date: Tue, 17 Nov 1992 20:35
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In article <1992Nov17.075719.23612@riacs.edu> gt8741b@prism.gatech.edu (Chris Adams) writes: >Can someone tell me what the frequencies of the buttons on a telephone generate >and what the dial tone frequency is? I am trying to build something, and I >need to recognize a dial tone, and generate button presses. >-- I forgot the dial tones for you... from CCITT Document APIII-84 Use Frequencies Power * Cadence ------------------------------------------------------------------------ Dial tone 350 & 440 Hz -13 dBm0 Continuous Busy tone 480 & 620 Hz -24 dBm0 0.5 sec on/0.5 sec off Reorder tone 480 & 620 Hz -24 dBm0 0.2 sec on/0.3 sec off Audible ringing tone 440 & 480 Hz -16 dBm0 2 sec on/4 sec off Call waiting 440 Hz -13 dBm0 Single 500-ms pulse * Power per Frequency at Exchange where Tone is Applied Scott Standard disclaimers apply!
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Newsgroups: sci.electronics Path: arc1-ca.pugleaf.net!sparky!uunet!think.com!ames!elroy.jpl.nasa.gov!praha!fraser From: fraser@praha.jpl.nasa.gov (Scott Fraser) Subject: Re: Tone frequencies on telephone Message-ID: <1992Nov17.203550.12932@elroy.jpl.nasa.gov> Sender: news@elroy.jpl.nasa.gov (Usenet) Nntp-Posting-Host: praha.jpl.nasa.gov Organization: Jet Propulsion Laboratory References: <1992Nov17.075719.23612@riacs.edu> Date: Tue, 17 Nov 1992 20:35:50 GMT Lines: 34