This machine is a bit of a mystery.
It was actually missing its serial plate (if you look at some of the rear photos below you will see the serial plate looks ripped in half) but apparantly Jerry (that's him on the right) has been in communication with Nolan Bushnell himself. This particular unit was found in a storage shed with four other Computer Space's in central California and they all fit the description of four units that went "missing" with Nolan's former partner Ted Dabney.
I have not been able to contact Jerry, despite repeated attempts, to verify any of this information.