The record contains a 24 layer back plane with 10 signal layers, one clock layer, 11 reference layers, and two pad layers. Each side appears to be identical with a four by four array of 5 3/8 inch square connector pads and a row of rectangular socket pads. The whole board is covered with a stagared checker board array.
Date
1991
Manufacturer
Digital Equipment Corporation (DEC)
Identifying Numbers
Other number
L1
Layer number found in the upper right corner of the board
Other number
L24
Layer number found on the second side.
Other number
MREX116B
Found etched into the top layer in the bottom right corner of the board on both sides.
Other number
S3456789U
Found etched into each corner on the front and back.