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From: markz@ssc.UUCP (Mark Zenier)
Newsgroups: sci.electronics
Subject: Re: Teddy Ruxpin's Audio Frequency Modulatinon
Message-ID: <519@ssc.UUCP>
Date: 2 Mar 90 19:08:50 GMT
References: <12595@nigel.udel.EDU>
Organization: SSC, Inc., Seattle, WA
Lines: 18

In article <12595@nigel.udel.EDU>, berryh@udel.edu (John Berryhill) writes:
> 
> The data packets are about 8 milliseconds
> long with 4 milliseconds between them.  Inside each packet is some
> sort of triangle wave that has a variable delay at the upward zero
> crossing, i.e.
> ...
> Has anybody out there managed to figure out what sort of modulation
> this sucker uses?  

One of the winners in the Circuit Cellar Ink design contest last year was
a project for generating Teddy Ruxpin data.  They havn't published the
details yet.

It looks like the pulse postion modulation used in radio control, where
the analog value is encoded in the time between pulses.

markz@ssc.uucp