30 Apr
2009
30 Apr
'09
9:42 p.m.
Looks like very early JROM jumperable read only memory.
It is clearly 10x10 array with 10 selectable coils per core providing full 10 bit
programability.
IBM 700/7000 series used BDC (binary-coded decimal).
Beyond that I am only guessing ...
The other Bob
On Thu, 30 Apr 2009 13:56:20 -0400 (EDT), Mike Loewen wrote:
Can anyone identify these boards?
http://sturgeon.css.psu.edu/~mloewen/DSC01381.JPG
http://sturgeon.css.psu.edu/~mloewen/DSC01382.JPG
http://sturgeon.css.psu.edu/~mloewen/DSC01463.JPG
They're stamped IBM, with etched numbers
LBJ5360, LBJ5403 and LKJ12470.
The owner says they were given to him in 1978, and were supposedly from
North Bay, Ontario.
Mike Loewen mloewen at cpumagic.scol.pa.us
Old Technology http://sturgeon.css.psu.edu/~mloewen/Oldtech/