I too have one of these little gems . I believe that  mine says Rochester N.Y. on the front sticker/label . I sounded great   and yes it has/had 2 of the large 9 volt batteries . one volume and one tone . to power it up you just  put the guitar cord into the jack . there also was a speaker out on the back . I was hoping  to get mine fixed as it had incredible tone. I have been reading thought the slew of messeges but havent finished them all . I was hoping somebody  came up with a schematic that I can bring  to a repair guy as I really am not one .  Is anybody  confident in what  has been submitted here? The only  reason I found you guys was that  everyonce in a while I try a search  for Mighty Atom on yahoo. Alas I have found hope!