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From: BRUCE@ccavax.camb.com (Barton F. Bruce)
Newsgroups: comp.dcom.telecom
Subject: Re: DTMF Decoder Wanted (or Chips/Schematics)
Message-ID: <14411@accuvax.nwu.edu>
Date: 6 Nov 90 14:42:52 GMT
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In article <14220@accuvax.nwu.edu>, aardvark!steve@tessi.uucp (Steve
Willoughby) writes:

> 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.

Get the chip handbooks from several of the major chip houses. There
are often seperate handbooks for telecom devices. There are plenty of
TT chips made.

If you are just tinkering, go to Radio Shack. They have TT decode
chips, but are hardly where you need to go if you are going to make a
product.

BTW, just use a DTMF decode chip. DON'T try to do it yourself.