Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!ncar!tank!eecae!cps3xx!usenet
From: usenet@cps3xx.UUCP (Usenet file owner)
Newsgroups: sci.electronics
Subject: Re: RS-232 for voice
Message-ID: <3999@cps3xx.UUCP>
Date: 31 Jul 89 19:20:13 GMT
References: <9185@kean.mun.ca>
Reply-To: beyer@frith.UUCP (Don W Beyer)
Organization: Engineering, Michigan State University, E. Lansing
Lines: 11


Perhaps some sort of delta-modulation could be used to save
bandwidth.  For instance, how about collecting four samples
and sending them all in one byte using four bit-pairs for the
deltas?  If care was taken to buffer them and play back at a
regular rate, the resulting Nyquist rate would be 3840Hz,
pretty decent for speech.  The hardware need be nothing more
than an ADC, modulator, uart, uart, buffer, demodulator, DAC.
Of course, the delta modulation would be pretty coarse, and 
could probably stand to be devised by someone with knowledge
of this...