18 Sep
2018
18 Sep
'18
10:27 a.m.
From: Pierre Gebhardt
As I don't have core memory modules available, I
thought of using MS11
memory, which, according to my research, seems to be an option for
11/40 systems.
Err, which kind of MS11? There are lots of different ones:
http://gunkies.org/wiki/MS11
and they don't all work in every UNIBUS PDP-11!
Your options are the -E/-J group, and the -L, but the latter are a bit hard
to find, and expensive. (There may be non-DEC equivalents, but I don't know
about them.) They all need a MUD backplane such as the DD11-C or DD11-D.
(IIRC, the -M has a 'UNIBUS' jumper, but the card uses non-standard voltages
on the backplane; 12V instead of 15V, IIRC.)
Does that mean that a single H745 regulator might be
sufficient for my
needs?
If you're not using a lot of MM11-L, you would definitely only need one H745,
no matter what configuration you have. (Note that if you have an old
machine/harness, there's a jumper you have to add if you have only a single
H745; see the second paragraph on page 6-18 of DEC-11-H40SA-B-D.)
Noel
18 Sep
18 Sep
4:59 p.m.
Am Dienstag, 18. September 2018, 16:27:49 MESZ hat Noel Chiappa <jnc at
mercury.lcs.mit.edu> Folgendes >geschrieben:
? ? > From: Pierre Gebhardt
? ? > As I don't have core memory modules available, I thought of using MS11
? ? > memory, which, according to my research, seems to be an option for
? ? > 11/40 systems.
Err, which kind of MS11? There are lots of different ones:
? http://gunkies.org/wiki/MS11
and they don't all work in every UNIBUS PDP-11!
Your options are the -E/-J group, and the -L, but the latter are a bit hard
to find, and expensive. (There may be non-DEC equivalents, but I don't know
about them.) They all need a MUD backplane such as the DD11-C or DD11-D.
Indeed, these are MS11-LB boards, but I don't know yet, if they work. Got them a long
time ago with a bunch of other untested unibus boards. With the BA11-F enclosure actually
came a DD11-DK backplane.
On Henk's website, I saw that one of his systems also has a DD11-DK backplane mounted
in it despite the shorter
cable lengths compared to a DD11-DF according to what Paul Anderson wrote.
I will have a look at this as soon as I have time and will extend the cables accordingly,
if required.
Thanks a lot for all the great hints provided so far by the list member :)
All the best,
Pierre
19 Sep
19 Sep
5:09 p.m.
On Tue, Sep 18, 2018 at 8:27 AM, Noel Chiappa via cctalk <
cctalk at classiccmp.org> wrote:
(Note that if you have an old
machine/harness, there's a jumper you have to add if you have only a single
H745; see the second paragraph on page 6-18 of DEC-11-H40SA-B-D.)
I totally missed that. It wasn't in the previous edition, DEC-11-H40SA-A-D.
However, now I see that both editions mention that the H744 in slot C is
optional, which I also was not previously aware of.
Although I've had a few 11/40 machines, I didn't often have to do anything
about the power supplies other than check the DC voltage and ripple.
20 Sep
20 Sep
2:22 a.m.
I grabbed a 11/60, 11/35 system manual. wanting to see hot power was set up
in the BA11-D and -K, only to find it dealt with the BA11-F only.
It does state the H754 in used with the MF11-U/UP. needless to say, there
are different plugs for slot "E" and possibly a change or a jumper.
I will look for a 11/35 book specifically next time I go downstairs.
My 11/40 does have 2 H745s in it. I see no reason to use both at this
point. I think one can supply enough current unless you overload it with a
bunch of 8K core.
I plan on putting either 8 16K core stacks in(for winter only) or an
MS11-LD (256KB).
Pierre, a lot of my bricks are buried. I'll try to did them out tomorrow.
Thanks, Paul
On Wed, Sep 19, 2018 at 4:09 PM, Eric Smith via cctalk <
cctalk at classiccmp.org> wrote:
On Tue, Sep 18, 2018 at 8:27 AM, Noel Chiappa via
cctalk <
cctalk at classiccmp.org> wrote:
(Note that if you have an old
machine/harness, there's a jumper you have to add if you have only a
single
H745; see the second paragraph on page 6-18 of
DEC-11-H40SA-B-D.)
I totally missed that. It wasn't in the previous edition, DEC-11-H40SA-A-D.
However, now I see that both editions mention that the H744 in slot C is
optional, which I also was not previously aware of.
Although I've had a few 11/40 machines, I didn't often have to do anything
about the power supplies other than check the DC voltage and ripple.
2:24 a.m.
I also saw some notes about different wiring harnesses for different serial
numbers. A lot to be careful with.
On Thu, Sep 20, 2018 at 1:22 AM, Paul Anderson <useddec at gmail.com> wrote:
I grabbed a 11/60, 11/35 system manual. wanting to see
hot power was set
up in the BA11-D and -K, only to find it dealt with the BA11-F only.
It does state the H754 in used with the MF11-U/UP. needless to say, there
are different plugs for slot "E" and possibly a change or a jumper.
I will look for a 11/35 book specifically next time I go downstairs.
My 11/40 does have 2 H745s in it. I see no reason to use both at this
point. I think one can supply enough current unless you overload it with a
bunch of 8K core.
I plan on putting either 8 16K core stacks in(for winter only) or an
MS11-LD (256KB).
Pierre, a lot of my bricks are buried. I'll try to did them out tomorrow.
Thanks, Paul
On Wed, Sep 19, 2018 at 4:09 PM, Eric Smith via cctalk <
cctalk at classiccmp.org> wrote:
On Tue, Sep 18, 2018 at 8:27 AM, Noel Chiappa via
cctalk <
cctalk at classiccmp.org> wrote:
(Note that if you have an old
machine/harness, there's a jumper you have to add if you have only a
single
H745; see the second paragraph on page 6-18 of
DEC-11-H40SA-B-D.)
I totally missed that. It wasn't in the previous edition,
DEC-11-H40SA-A-D.
However, now I see that both editions mention that the H744 in slot C is
optional, which I also was not previously aware of.
Although I've had a few 11/40 machines, I didn't often have to do anything
about the power supplies other than check the DC voltage and ripple.
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