From: "Jeffrey S. Sharp" <jss(a)ou.edu>
To: "PUPS Mailing List" <pups(a)minnie.cs.adfa.edu.au>
Subject: [pups] Cabinet Questions
Date: Tue, 20 Mar 2001 01:30:38 -0600
In the peripherals manual, the H960 cabinet comes in two models: the -C and
the -D. The -D model has a sliding drawer in the lower half of the cabinet
that provides space for 9 "system units". What are these "system
How big are they? What goes there? When do you need the -D model?
A system unit (SU) was the fundamental hardware building block of an
11/20 and many subsequent PDP's. It was a frame 16.5 inches by 2.25
inches that held 3 blocks of dual card sockets. Each socket block was
nominally 5.25 inches by 2.00 inches and could hold four "dual" cards
spaced at 0.5-inch intervals. Thus the whole SU could hold four "quad"
cards plus two "dual" Unibus connectors in its four rows by six
sockets. Later production included a double-wide system unit that
could hold nine cards.
Typical things that came built into one SU include 4kW (8kB) of core
memory and RK05 disk controllers. There were also SU's that were
pre-wired to hold four Small Peripheral Controllers (SPC's). Typical
SPC's included single-line serial interfaces, and line-printer controllers.
Think of the H906-D as an 11/40 or 11/45 without any backplane or cards.
Let's say I want to ultimately build a 11/70
system with a TE16/TM03 (in its
own cabinet, I guess), a TU56/TC11, a paper tape reader/punch (PC11?), 3 or
4 RK05s, and 1 or 2 RP04s. What set of cabinets do I need for this system?
Assume the CPU has the SETASI memory upgrades and not core.
Una vez mas... Let's say I want to ultimately build a 11/40 system with the
same peripherals as above minus the RP04s and with a TU10/TM11 as the
9-track. What kind of cabineting do I need here? Assume the CPU has MOS
memory and not core.
I think you could put that system into two H960 racks. Figure 1/2 of a
rack for the 11/40, 1/3 of a rack for the TU10. RK05, PC11, TU56 each
take up 1/6 of an H960. With MOS memory you should have plenty of room
in the 11/40 frame itself for the necessary one-SU controllers for
RK05, TU56. Especially if you take out the 2-SU frame that originally
held the core memory. I'm not sure where you put the TM11, I never
actually had a real one, just emulated controllers that fit in one SU.
Finally, how much weight can a H960 support?
Probably 500 or 600 pounds. If you can, look for the older H960's with
welded frames rather than pop rivets.
carl lowenstein marine physical lab u.c. san diego