The Anachronistic Code, Book One: Déjà Me‪.‬

It's 1985, and Josh Donegal is seventeen…AGAIN.
Josh has shifted back in time some fifty years and he doesn't know how, much less why. What’s more, he's noticing temporal anachronisms—minute changes that would only be obvious to somebody who had lived through the 80s before.
Is Josh alone? Is somebody trying to send out a coded message?
He's going to have to find all the changes to figure it out.