A suggestion is to add info-pdp11 to these kind of questions, since some
of us don't really have the energy to plow through all of cctalk... :-)
Anyhow, just like some others have suggested, it definitely sounds like a
hung Unibus.
Check NRP jumpers on all the slots. Remove the massbus interfaces. See if
you can access anything in the I/O page.
Those are the first things I'd try.
Also, the 11/70 have different regulators for different parts of the
backplane, and one regulator us just for the Unibus slots at the
end. Check that regulator as well.
Also, I hope you have a good terminator card. :-)
Johnny
Johnny Billquist || "I'm on a bus
|| on a psychedelic trip
email: bqt(a)update.uu.se || Reading murder books
pdp is alive! || tryin' to stay hip" - B. Idol