On Saturday, August 20, 2022 at 8:11:41 AM UTC-4, Bill Gunshannon wrote:
> I have never had a PDP-11 module third-party or otherwise that had
> anything on the board that said if it was QBUS or UNIBUS. Always
> had to refer to the documentation for that.
Not to mention that there are many, many modules that are neither -- they depend on a specific SU (system unit, "backplane") as part of a CPU, device controller, or other assembly that may-or-may-not have a bus interface at an "edge".
Being hex-height doesn't even rule out Qbus (thank you PDP-8/A :->).