17 Sep
2018
17 Sep
'18
4:09 p.m.
From: Henk Gooijen
As far as I know, the 11/40 uses only one H745.
Depends on what kind of memory it has. If MF11-L, it has two H745's; if
MM11-U, it has an H745 and an H754.
(The harness has two different connectors for the 5th 'brick', so it can
handle either kind. At least, that's the situation on the later machines
[serial numbers above 6000]; early production /40's only support the MF11-L,
and you have to use special add-on harnesses to support an MF11-U in them;
see DEC-11-H40SA-B-D, Chapter 6 for the details.)
Noel
18 Sep
18 Sep
4:11 a.m.
? ? > From: Henk Gooijen
?? > As far as I know, the 11/40 uses only one H745.
Depends on what kind of memory it has. If MF11-L, it has two H745's; if
MM11-U, it has an H745 and an H754.
(The harness has two different connectors for the 5th 'brick', so it can
handle either kind. At least, that's the situation on the later machines
[serial numbers above 6000]; early production /40's only support the MF11-L,
and you have to use special add-on harnesses to support an MF11-U in them;
see DEC-11-H40SA-B-D, Chapter 6 for the details.)
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.
The system manual states on page 6-7 that the base power configuration consists
of two H745 regulators and that one may be swapped with a H754 in case MF11-U
memory is used.
Does that mean that a single H745 regulator might be sufficient for my needs?
All the best,
Pierre
4:32 a.m.
I'll check my system tomorrow if I can. If you are using a DEC MS11-LB or
LD or compatible, you will need a DD11CK or DK backplane. If used in a
BA11-BF, you will Need DD11-CF or DF, which is the same as the CK/DK, but
with a longer wiring harness.
DEC made an "extension cable" to do this, but thew are not many around. Or
just replace it yourself.
Paul
On Tue, Sep 18, 2018 at 3:11 AM, P Gebhardt via cctalk <
cctalk at classiccmp.org> wrote:
MF11-L,
From: Henk Gooijen
As far as I know, the 11/40 uses only one H745.
Depends on what kind of memory it has. If MF11-L, it has two H745's; if
MM11-U, it has an H745 and an H754.
(The harness has two different connectors for the 5th 'brick', so it can
handle either kind. At least, that's the situation on the later machines
[serial numbers above 6000]; early production /40's only support the and you have to use special add-on harnesses to
support an MF11-U in them;
see DEC-11-H40SA-B-D, Chapter 6 for the details.)
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.
The system manual states on page 6-7 that the base power configuration
consists
of two H745 regulators and that one may be swapped with a H754 in case
MF11-U
memory is used.
Does that mean that a single H745 regulator might be sufficient for my
needs?
All the best,
Pierre
11:45 a.m.
Hi Pierre,
Just to give you an idea, I will go to my museum either on Wednesday or on Saturday.
Till then,
Henk
________________________________
Van: cctalk <cctalk-bounces at classiccmp.org> namens P Gebhardt via cctalk
<cctalk at classiccmp.org>
Verzonden: Tuesday, September 18, 2018 10:11:43 AM
Aan: General Discussion: On-Topic and Off-Topic Posts
Onderwerp: Re: Looking for two DEC H445 power bricks for PDP 11/40 project
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.
The system manual states on page 6-7 that the base power configuration consists
of two H745 regulators and that one may be swapped with a H754 in case MF11-U
memory is used.
Does that mean that a single H745 regulator might be sufficient for my needs?
All the best,
Pierre
From: Henk
Gooijen
As far as I know, the 11/40 uses only one H745.
Depends on what kind of memory it has. If MF11-L, it has two H745's; if
MM11-U, it has an H745 and an H754.
(The harness has two different connectors for the 5th 'brick', so it can
handle either kind. At least, that's the situation on the later machines
[serial numbers above 6000]; early production /40's only support the MF11-L,
and you have to use special add-on harnesses to support an MF11-U in them;
see DEC-11-H40SA-B-D, Chapter 6 for the details.) 
19 Sep
19 Sep
5:01 p.m.
On Tue, Sep 18, 2018 at 2:11 AM, P Gebhardt via cctalk <
cctalk at classiccmp.org> wrote:
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.
The system manual states on page 6-7 that the base power configuration
consists
of two H745 regulators and that one may be swapped with a H754 in case
MF11-U
memory is used.
Does that mean that a single H745 regulator might be sufficient for my
needs?
If you don't have core memory, you should have three H744 in slots A, B,
and C, and two H745 in slots D and E.
2083
days inactive
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days old
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