I too have been searching for documentation/schematics for the Cambridge Memories, Inc. Expandacore18 4k core memory boards. I have an old Diversified Numeric Applications Med PL/185 machine which is a clone of the Raytheon 703. This machine has 16k of core with 4 of these boards. -- THE BLUES IS THE TRUTH. IF IT'S NOT THE TRUTH, IT'S NOT THE BLUES. (Willie Dixon)