I've recently become interested in the original Teddy Ruxpin that operated by playing 8-track cassette tapes. The 8 channels on the tape were used in a creative way to ensure that Teddy's animation would line up correctly with the audio. This link gives more information on how it's done. It seems like channel 1 is perhaps the channel used for the audio, and the other channels are used for eyes, upper and lower jaw, and whether the audio is supposed to come from Teddy or Grubby (a different toy).
I can find lots of tutorials on hacking Teddy using open-source python libraries, a wi-fi connection, replacing the cassette deck with a microchip, blah blah BLAH. I want to create my own Teddy Ruxpin cassette tape that can be inserted into the toy like one of their own tapes and will animate according to my coding.
I can't find any information on how the animation channels were specifically used to determine the mouth and eye movements, however. What do you guys think? Is there an easy way to find this out? And if not, what's the best way to get to work understanding it myself? What kind of equipment is good for editing individual tracks on an 8-track cassette tape, and where could I get it?