WTB: DEC Rainbow Expansion Memory

Warner Losh imp at bsdimp.com
Thu Apr 13 15:20:06 CDT 2017

On Thu, Apr 13, 2017 at 12:00 PM, shadoooo via cctech
<cctech at classiccmp.org> wrote:
> Hello,
> I'm in the pretty same condition, I have a Rainbow 100B without memory
> expansion.
> Not sure however, about the correct board number, which would fit the 100B.
> What should I search for?

The DEC part numbers for these are PC1XX-AY (128k) and PC1XX-AZ
(256k). I'm not sure what the board numbers are, and some auctions
list those instead.

They are the same board. There's 4 switches on the board. One for each
of the 3 banks to select between 64kbit chips and 256kbit chips. You
want 4164 or 41256 for the board. It's super easy to upgrade (I bought
a AY back in the day and then 18 months later I bought 27 41256 chips
and swapped them out in about 10-15 minutes.

I'm not sure what the 100A needs. I have no experience with the 100A hardware.


More information about the cctech mailing list