hi there!
hi pete!
> If I were to be really picky, I'd
> say you meant microPDP-11/23.  11/23-plus
> would mean a BA11-S enclosure with
> a different type of backplane :-)
mine is about 40 inch high, 19 inch wide and
as deep as
the rl02 is. the "microcomputer interfaces
1983-84" shows
some pictures of boxes: is might be the
BA11-S
>
> The backplane itself has a
> model number; for a BA23 it should
> be H9728-A.
>
on the backplane i found H9276-A.
i don´t know what -A means, but it should be
a Q22/CD
so no serpentine?
>
>
> I'm guessing you have a single
> memory board, probably an MSV11-Q (M7551),
> and an RLV12 (M8061, one quad
> board) rather than an RLV11 (two
> quad boards)
> -- if not, that makes a difference
> to the layout.  I'm also guessing at a
> DEQNA (M7504) rather than any
> other Ethernet controller, but it makes no
> difference to the placement, so
> long as it's a dual-height board.
>
now i´ve got the numbers here:
CPU:   M8190-AE      KDJ11-B
MEM:   M7551-CC      MSVC11-QC
RL02:  M8061
DELQA: M7516
RQDX3: M7555
DEQNA: M7546

> There were some differences about whether
> an FPU could be fitted (due to an
> error on the original boards); those that
> would not take an FPU were only
> sold as KDJ11-BC and all had 15MHz clocks.
>  Others with 15MHz clocks were
> sold as KDJ11-BB (upgradeable but FPU not
> fitted).  There are also some with
> 18MHz clocks, these were sold as
> KDJ11-BE, -BF, or higher.
> Normally an 11/83 has a KDJ11-BE or higher
> suffix.  Early 11/73 are 15MHz.
> Just to add to the confusion, the -Bx
> suffix actually refers to the
> EPROMs on the board, not the clock speed or
> the FPU.  The *only* difference
> between a normal KDJ11-BE or -BF or -BH is
> the firmware in the EPROMs.

hmmm, this is really confusing, since i have
AE
can it take an FPU? maybe it has a fpu? what
does
the fpu look like?

>
> However, the biggest difference
> between 11/83 and 11/73 is whether the
> memory is used as QBus memory, or
> PMI memory, which is faster.  All of the
> KDJ11-B boards can use PMI memory.
>  Beware, not all quad memory boards are
> PMI-capable, but all the 1MB and
> bigger ones that I can think of are.

so i should put in first memory then cpu.
>
> > do all 11/83 use PMI ?
>
> Yes.  They will work with QBus
> memory instead (and if you put a PMI board
> after the processor instead of
> before it, it will run as normal QBus
> memory)
> but then what you have is
> effectively an 11/73, not an 11/83.
>
>
> Literally "hanging"?  Not fixed to
> the front of the BA23?  Is this actually
> a floor-standing (or possibly
> rack-mounting) BA23 with space for
> a TK50 and
> a drive unit, or a rackmount
> BA11-S or BA11-N chassis with no space for
> drives?
well it´s a BA11-S i suppose by now.
the panel and the pcb wich connects to the
two disks were literally "hanging"
when i got the box, it was a pdp-cabinet
and a second 19inch rack, containig old,
unused stuff and the tk50 and those 2 disks
there is a separate power supply for the
disks
now the tk50 and the disks are on a separate
table
>
> Neither have I.  DEC used
> pushbuttons for the disk controls
> on microPDP-11
> panels.  Each section is separate,
> though; it sounds like someone has
> replaced the pushbuttons or used
> third-party sub-panels.  The round hole
> (if this is an original DEC panel)

it´s a original dec panel and dec pcb.

> is for the badge that says whether it's
> a microPDP-11/23, microPDP-11/73,
> microPDP-11/83, microPDP-11/53, etc.  The
> rectangular hole is for the power
> switch in a BA23 or BA123 cabinet.

i suppose they changed CPU and memory from
the pdp11/23plus and put in half a 11/83.
the 3 switches at the frontbezel of the
BA11 work, the other "front"panel at the back
(from a 11/83) is only used to put the disks
online and write protect them. this would
also
explain why there is a connector "hanging"
at the rear-frontpanel.

a weird pdp.

--lothar