Soon after Motorola released the powerful 6809 CPU, Southwest Technical Products Corporation (SWTPC) created a new computer to use it. This 6809 model used an MP-B3 motherboard which supported 56k of memory and included a set of fifty parallel traces to carry the signals of their custom SS-50 bus (S-100 was the standard at the time), and another set of thirty for the SS-30 I/O bus. There are only a few IC’s on the motherboard, mostly just the male Molex connectors onto which the computer add-on boards would plug in. The outward case design is almost identical to that of the earlier 6800 model machines and used textured, black sheet metal for the cover.
The serial number of my unit is 6601. The computer came in two flavors, the 69K (Computer Kit ) and the unit I own: the 69A which was pre-assembled and cost $695.