Strange third party board in PDP-11/45

[Bob Smith]

any identification number sn front or back? can tell from just that shot.


On Sat, Jul 21, 2018 at 2:37 PM, Mattis Lind via cctalk
<cctalk at classiccmp.org> wrote:
> This board was sitting in slot 21 of the backplane in a 11/45
>
> https://i.imgur.com/ZYWZQCo.jpg
>
> What kind of board is this?
>
> It has 26 bipolar RAMS. Fairchild 93415 1kbit SRAM.
>
> The manufacturer might be ACT whatever that is.
>
> My guess is that it is some kind of cache board? It is connected to both
> unibuses in the machine.
>
> Better ideas? Documentation?
>
> /Mattis