It's time to restore the 11/45.

Jacob Ritorto jacob.ritorto at
Wed Feb 4 12:43:27 CST 2015

  Having gotten the 11/34 rig up to a good spec, I'm sufficiently excited
to tackle the 11/45.  It's been powered off since 2004, when I briefly
turned it on only to find a wild jumble of lights and that none of the
front panel switches or knobs did anything to the lights.  Couldn't get it
to run or deposit values or *anything*.  I therefore assumed it was badly
broken and so left it until now.  It has stayed perfectly high and dry but
has gone to extremes in temperature as the storage isn't climate controlled
(this is in western Pennsylvania).  And there's a lot of dust.

  I'm not going for museum perfection, but want it to be very presentable
(lobbying to keep it as my 'art' in the living room long term if it's
presentable enough :) and functional.

So I'm looking for tips on how to go about it?  I was thinking:

1) Truck machine to living room, note positions of all wires / boards.
Photograph, remove and clean dust from them.  Place on antistatic bench.

2) Thoroughly blow out dust and debris, vacuum backplane and wipe down
chassis and wires with damp cloth.

3) Map out desired hardware config: I have available two Fujitsu 160 disks,
three Fujitsu M2333K disks and two Fujitsu M2372K disks.  I need to decide
how to rack and cable at least two, possibly up to four of them as the 8"
ones have no mounting hardware.  Operational status on all is "hopeful."  I
have two Emulex SC21s and an SC41 as well as an unmarked Xylogics Unibus
SMD board.  I'm also tempted to mount an RX02 drive as I have a controller
and quite a mountain of floppies supposedly containing weird old stuff.  I
need to source an ethernet board and whatever cabling / bulkhead stuff
follows.  DZ11, its dist panel and a Diablo 630 printer would be nice, too.

4) This would also be a good time to broach the subject of whether or not
the capacitors need special love, or if that just adds more risk of
destroying something.  Those familiar, please chime in as the archive is
currently missing so I can't refer to the recent threads on this subject.
Datapoint: I didn't mess at all with power supply / caps on my 11/34, which
was stored right beside the '45 for the same timespan and it's running
great now.  Datapoint 2: with my amateur electronics skills / status,
there's admittedly some risk just having me poking around in there,
"learning" things :-\   Plus, I'm afraid of death from esoteric high
voltages that I hear are present in these old power supplies.  Is the 11/45
one of them?  In a nutshell, this analog / power stuff is FAR FROM my
forte; some hand-holding here would be most appreciated.

5) Insert an expendable Unibus module and power up; check & tune power.  I
need direction on how to go about this.  Also, the bottom H742A power
chassis isn't completely populated.  Not sure if that's acceptable, on
purpose or bad.

6)  Reassemble, tidying up issues like missing / loose screws, rubbing
cables, etc. along the way.

7) rt, 2.11BSD, rsx, rsts/e!   (mostly via vtserver -  I have a tu10 that I
could get in on this deal, but its roller rubber has turned into goo and
two cabinets in the living room is more than "pushing it."  Later date on
that puppy. )

Current module config starting from front of cabinet (yes, there are some
gaps and M9200 jumpers I don't mention, too):
M9301 + M787
M7800 + M9200 jumper
Unibus cable runs out to third party external memory chassis, "Monolithic
Systems Corp" Type MO v11/PDP11 P/N 300-0058-000, which is three quarters
populated.  If this memory is broken, I'm planning to use an M7891 instead
(is that OK?).
No Unibus termination after that.  Is that weird / bad?

Does this current config seem sound?  Is there a problem obvious just from
this description that would account for the unresponsive front panel?

Here's the power supply situation: There are two H742A power chassis.  Top
contains h744, h744, h744, h744, h745.  Bottom contains H745, H746, open,
H744, open.

big thx!

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