>>>> "Tony" == Tony Duell
<ard(a)p850ug1.demon.co.uk> writes: 
 >  I looked in my 11/34 CPU box.  There's room
for a 4-slot
> backplane.  I currently have two 9-slot backplanes.  Can I use an
> M9202 to connect the 9-slot backplane to the RK11-D 4-slot
> backplane? 
 Tony> I don;'t see why not. The M9202 has 2' of Unibus cable folded
 Tony> up inside to give a little delay. Otherwise it's the same as
 Tony> the M920. I think you can use either.
That rings a bell.  The M9202 is needed sometimes instead of the M920
to spread out reflections.  There's a pile of detail in
http://bitsavers.org/pdf/dec/unibus/UnibusSpec1979.pdf
       paul