Mystery Board

[Jeff Lemke <lemke@terra.cira.colostate.edu>]

I've come across a board by "Stellation Two".  The line below that says
"The Mill".  Copyright date is 1980.  There are 8 chips on the left end
of the board in two rows of 4, at locations labled U15 and U16 on the
far left end, and then U1 to U6.  The next chip at U7 is a large one,
labled 3C1 on the first line, and HD6809EP on the line below that. 
There are three more chips to the right of that at locations U8 to U11,
with U11 actually being an empty socket.  There are three more chips
mounted vertically in respect to each other on the far right end of the
board, at locations U12 to U14.  There are no other cables or connectors
on this board, and no writing on the back.

Anybody know what this board is?

Jeff Lemke