Path: utzoo!utgpu!watmath!att!dptg!rutgers!cs.utexas.edu!sun-barr!newstop!texsun!texbell!vector!telecom-gateway
From: jjjs@cbnewsc.ATT.COM (james.j.sowa)
Newsgroups: comp.dcom.telecom
Subject: Re: DTMF frequencies
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Date: 8 Aug 89 12:39:40 GMT
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X-TELECOM-Digest: volume 9, issue 281, message 8 of 10

>X-TELECOM-Digest: volume 9, issue 275, message 6 of 12
>What are the frequencies of the various tones used for DTMF?
>Thanks,

Here is the DTMF chart taken from "Notes on Distance Dialing" January 1975

                    HIGH-Group
                   Frequencies  (Hz)


                   1209    1336    1477    1633

             687     1       2       3       A
  LOW GROUP
FREQUENCIES  770     4       5       6       B
    (HZ)
             852     7       8       9       C

             941     *       0       #       D

==================================================================
Jim Sowa