Charles wrote:
But there
is no manufacturer's info except what looks like "K-3VO" in the
lower left corner,
That doesn't tell you anything about the manufacturer of the product.
It just indicates the flame-resistance of the PCB material, or some
such thing.
I don't even have a SWAG as to what that card is. I'm a little dubious
about it belonging in a PDP-8/a, but I suppose anything is possible.
Eric