Adding additional memory to 11/45s

[utzoo!duke!decvax!ucbvax!FRANK at UTAH-20]

From: Randy Frank <FRANK at UTAH-20>
Does anyone know of available products that enable one to extend directly
addressable memory on a PDP 11/45 above 256KB?  Ideally, such a product
would emulate 11/44 or 11/70 style 22 bit addressing (i.e., would provide
Unibus mapping registers).  I thought I had seen a memory board which also
had on board 18 to 22 bit address mapping, but can't seem to find any
references.

I'm open to home-grown solutions, but a commercially available product
is preferable!

(I am aware of memory products that are made to look like disks for high
speed swapping, but these seem less preferable than truly adding more
directly addressible memory).

Thanks for any pointers.

Randy Frank
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