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From: aardvark!steve@tessi.uucp (Steve Willoughby)
Newsgroups: comp.dcom.telecom
Subject: DTMF Decoder Wanted (or Chips/Schematics)
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Date: 31 Oct 90 06:01:01 GMT
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Reply-To: Steve Willoughby <aardvark!steve@tessi.uucp>
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X-Telecom-Digest: Volume 10, Issue 780, Message 5 of 13


I'm playing around with building a circuit that will, among other
things, (try to) recognize DTMF tones played into it.  An example
application of this would be to make your own voice-mail system (the
circuit would look for DTMF keypad keys pressed on the incoming line
and signal a CPU to do something, like play or record a message.)

The problem is that I can't seem to find any references to
DTMF-decoder chips or schematics of discrete-component circuits to do
this function.  Any help would be appreciated.

Thanks in advance,


Steve Willoughby N7PFJ 
steve@aardvark.pdx.com 
(sun.com!nosun!tessi   
     !aardvark!steve)