Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!ames!lll-winken!oodis01!uplherc!wicat!m5!keith
From: keith@m5.UUCP (Keith J. McQueen)
Newsgroups: sci.electronics
Subject: Re: DTMF (Touch-Tone) --> RS-232 Conversion
Message-ID: <00106@m5.UUCP>
Date: 27 Jan 89 19:07:32 GMT
Organization: WICAT Systems Inc. Orem, Utah (Engineering-R & D)
Lines: 10



Myself along with a group from our local Ham Radio ARES group
has designed a DTMF decoder circuit that we use for DTMF signalling,
remote control and paging.  One of the many features it incorporates
is a CMOS level ASCII serial output (RS-232 but 5v levels) of all
tones recieved.  The project uses a microprocessor for control, and
draws about 12 microamps when no audio is present.  Costs about $50
to build.

This could be what you are looking for.