This was a toy that looked like a folder coat hanger that was used to trace small pictures and would draw larger images on the other arm of the toy. I don't know what it was called but hasbro or matell i believe made it. If you can find me the name, i have been looking for one for a long time.
I'm fairly certain the "art tracer" you describe was called "Copy Cat". I DESPERATELY wanted one when I was a kid, possibly Christmas '76, or maybe the year before. That's when I started to doubt about Santa, btw, because it was the ONLY thing I asked for and I didn't get it, LOL