The Rockman was invented by M.I.T. graduate Tom Scholz, who also happens to be the guitarist for the band "Boston".

First issued in 1980, the Rockman was slightly smaller than a VHS video tape.  It was battery operated and was primarily intended for headphone use (it came with a belt clip).  It was also suitable for recording, although it was extremely noisy (lots of "hiss").

Adams and I used the Rockman extensively during our writing and demo-ing in the early to mid-1980s ... first the "pocket" model, pictured above, and later the rack-mount model. 

The Rockman was used to create the guitar sound on our demo of "Into The Fire".