From: Henk Gooijen
As far as I know, the 11/40 uses only one H745.
Depends on what kind of memory it has. If MF11-L, it has two H745's; if
MM11-U, it has an H745 and an H754.
(The harness has two different connectors for the 5th 'brick', so it can
handle either kind. At least, that's the situation on the later machines
[serial numbers above 6000]; early production /40's only support the MF11-L,
and you have to use special add-on harnesses to support an MF11-U in them;
see DEC-11-H40SA-B-D, Chapter 6 for the details.)
Noel