12 Aug
2005
12 Aug
'05
2:27 p.m.
Hi
Is there a list of the various pdp-11 unibus backplanes anywhere?
My 11/44 has a DD11-DF in it which is impossible to get cards into and
out of. It's like something is physcally wrong with it. Rather than
damage any cards I thought I'd replace it.
So, I looked at my 'space' 44 and found it had an RK611. That's nice,
but not helpful as I have no rk05's (yet :-)
It also has a DD11-B, which looks like it might work, since I only need
2 slots for the short term.
I was curious if there was a list somewhere of what stock unibs
backplane panels.
(like what's the difference between an DD11-DF and a DD11-DK?)
-brad
Brad Parker
Heeltoe Consulting
+1-781-483-3101
http://www.heeltoe.com
12 Aug
12 Aug
2:51 p.m.
On 8/12/05, Brad Parker <brad at heeltoe.com> wrote:
Is there a list of the various pdp-11 unibus
backplanes anywhere?
I do not know of a master list online.
My 11/44 has a DD11-DF in it which is impossible to
get cards into and
out of. It's like something is physcally wrong with it. Rather than
damage any cards I thought I'd replace it.
It takes a bit of force to get hex cards in a nearly-unused backplane.
I've bent latches trying to get boards in. The trick is to make sure
they are aligned with the slot guides, to wiggle the boards a bit
right when they touch down, and apply pressure evenly, including using
the entire edge stiffener, not just the levers to apply pressure. A
new backplane isn't necessarily going to be any easier to load up. Do
ensure that it's aligned, though - loosen the screws at the bottom (4?
6?) that hold it to its rails, and it might migrate a fraction of a
millimeter, if it's currently binding.
It's a _lot_ harder to mount hex cards in a DEC backplane than any PC
card - lots more points of contact, lots more force.
So, I looked at my 'space' 44 and found it had
an RK611. That's nice,
but not helpful as I have no rk05's (yet :-)
And it wouldn't help you if you did... the RK611 backplane is for RK06
and RK07 drives. The RK11D backplane is what you'd want to have to
use RK05s.
It also has a DD11-B, which looks like it might work,
since I only need
2 slots for the short term.
Perfect. A very useful backplane for small configurations. Don't
forget the two SPC (Small Peripheral Controller) slots for quad Unibus
cards (the TU80 interface is one of the more ordinary ones in machines
I've seen).
(like what's the difference between an DD11-DF and
a DD11-DK?)
In that particular case, the DD11-DF is meant to contain a CPU, not
just Unibus cards, (as do most Unibus CPU backplanes). The DD11-DK is
a larger version of your 4-slot Unibus backplane - Unibus slots, only;
no non-Unibus memory or MUD slots or anything that one might find in a
CPU backplane.
-ethan
3 p.m.
On Fri, 2005-08-12 at 15:51 -0600, Ethan Dicks wrote:
NO! The DD11-DF is meant to go in BA11-F chassis (21" tall ones) and
the DD11-DK is meant to go in BA11-K chassis (10.5" tall ones). The
difference is the length of the power harness. The DF is long and the
DK is short.
There are also DD11-CF and DD11-CK backplanes which are 4 slot versions
of the above.
--
TTFN - Guy
(like
what's the difference between an DD11-DF and a DD11-DK?)
In that particular case, the DD11-DF is meant to contain a CPU, not
just Unibus cards, (as do most Unibus CPU backplanes). The DD11-DK is
a larger version of your 4-slot Unibus backplane - Unibus slots, only;
no non-Unibus memory or MUD slots or anything that one might find in a
CPU backplane.
3:06 p.m.
On 8/12/05, Guy Sotomayor <ggs at shiresoft.com> wrote:
NO! The DD11-DF is meant to go in BA11-F chassis
(21" tall ones) and
the DD11-DK is meant to go in BA11-K chassis (10.5" tall ones). The
difference is the length of the power harness. The DF is long and the
DK is short.
Ah... sorry... my mistake. I'm not accustomed to the systems with
bays larger than the BA11-K. I thought I was speaking from memory,
but I was mistaken. That'll learn me.
-ethan
3:16 p.m.
On Fri, 2005-08-12 at 16:06 -0600, Ethan Dicks wrote:
On 8/12/05, Guy Sotomayor <ggs at shiresoft.com>
wrote:
If only our memories had parity! ECC would be better, but just knowing
it was wrong would be great!! :-)
--
TTFN - Guy
NO! The DD11-DF is meant to go in BA11-F chassis
(21" tall ones) and
the DD11-DK is meant to go in BA11-K chassis (10.5" tall ones). The
difference is the length of the power harness. The DF is long and the
DK is short.
Ah... sorry... my mistake. I'm not accustomed to the systems with
bays larger than the BA11-K. I thought I was speaking from memory,
but I was mistaken. That'll learn me. 
15 Aug
15 Aug
8:12 a.m.
At 03:51 PM 8/12/05 -0600, you wrote:
On 8/12/05, Brad Parker <brad at heeltoe.com>
wrote:
I've had similar trouble with the HP 1000 boards. I found that if I
clean the edge connectors and them wipe them with a rag slightly dampened
with WD-40 (mostly kerosene, a light oil) that the cards go in and out much
easier and I have a lot less intermitant contacts. I believe the oil
coating also helps reduce oxidation of the contacts.
Joe
Is there a list of the various pdp-11 unibus
backplanes anywhere?
I do not know of a master list online.
My 11/44 has a DD11-DF in it which is impossible
to get cards into and
out of. It's like something is physcally wrong with it. Rather than
damage any cards I thought I'd replace it.
It takes a bit of force to get hex cards in a nearly-unused backplane.
I've bent latches trying to get boards in. 
12 Aug
12 Aug
5:19 p.m.
So, I looked at my 'space' 44 and found it had
an RK611. That's nice,
but not helpful as I have no rk05's (yet :-)
If it is an RK611 (a 9 slot backplane with 5 hex cards in it IIRC), then
it's for RK06/RK07 drives. The interface is _very_ different to that for
the RK05.
IIRC (again), the 3 spare slots are one end of the RK611 are wired as SPC
slots and you can stick normal SPC cards in there (converesly if they're
empty, you need to put grant continuity cards in them).
Personally, I'd want ot konw why you can't get cards into the exising
backplane. It may be soemting simple like it's not aligned with the
cabinet properyl (so the board edge conenctor tabs don't quite line up
with the backpalne connectors. Try loosening the mouting screws for the
backplane and sticking a hex card (anything, you're not going to power it
up) in each end slot, then retighten the screws.
-tony
13 Aug
13 Aug
4:25 a.m.
Is there a list of the various pdp-11 unibus
backplanes anywhere?
1. The edited option/modules list, under DD11 you will see a lot
of variants. And it generally names "where used" too.
[Hard getting cards in]
The backplanes are generally attached to the backplane with captive
4:26 a.m.
Oops, to continue my last thought:
The backplanes are attached to the chassis with captive screws. If you
loosen them up you will find some wiggle-room to realign the slots
with the guides.
If the chassis has ever been physically abused (OK, if you dropped it
you probably put some abuse on the thing underneath too!) it may simply
be bent out of square.
Tim.
7070
days inactive
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ard＠p850ug1.demon.co.uk -
brad＠heeltoe.com -
ethan.dicks＠gmail.com -
ggs＠shiresoft.com -
rigdonj＠cfl.rr.com -
shoppa_classiccmp＠trailing-edge.com