Help collecting gear from west of Chicago

[Tony Duell]

> 
> Tony wrote:
> > Unibus and Qbus use the same double-sided 36 pin  (18 pin per side) 0.125"
> > pitch connectors. Q bus boards are normally dual or quad, Unibus are
> > normally quad or hrx.
> 
> To be overly pedantic:
> 
> Unibus boards are normally dual.  The only real Unibus boards you're likely
> to find are the terminators and bus jumpers.  If someone tries to tell you
> that a quad or hex board is a Unibus board, they're almost certainly
> mistaken, and it is probably really an SPC or MUD/SPC board.  Normally
> the only Unibus slots in a PDP-11 backplane are the A-B positions of the
> first and last slots, though there are exceptions to that in various
> places such as the PDP-11/45 and RH11 backplanes.

Overly pedanyic, yes....

Since the signals on an SPC slot are essentially those on the backplane 
interconnecting slots (which is what you're calling Unibus), I think it 
would be reasonable to say that the SPC boards are Unibus devices. 
Certainly DEC manuals do this (they talk about a Unibus serial board 
which is actually an SPC board, etc). 

-tony