Questions regarding a PDP11/34a

From: Netdiablo <>
Date: Wed Jun 13 09:25:27 2001

Hi everyone! Recently I've been taking a closer look at a system that I
rescued last
summer from the property disposition department of one of the local
higher education
concerns - a relatively well-equipped PDP11/34a along with a rather
broken RX02 disk

As far as I can tell, the PDP11 system is in fine working condition. I
had to put a
new power cord on it (the old one was chopped off when the system was
for some reason), but barring that, it powers up and the front panel
seems alive.
The machine has the following configuration:

M8256 PDP11/34a data paths module (KD11-EA)
M8266 PDP11/34a control module (KD11-EA)

M8204 Microprocessor, DMC-11 code, 1kb memory (KMC11-A)
M7867 SDLC or DDCMP sync interface (DUP11-DA)
M7867 SDLC or DDCMP sync interface (DUP11-DA)

M7856 RS-232 SLU with RTC (DL11-W)
BM873-YJ ??
M7859 Front panel console interface (KY11-YB)
M9202 Unibus connector

M7850 Parity for G651, MS-11 (MM11-BP/CP)
G652+H222A 16 kword 16 to 18 bit motherboard with 16 kword 18 bit core
stack (MM11-DP)
G652+H222A 16 kword 16 to 18 bit motherboard with 16 kword 18 bit core
stack (MM11-DP)

M9202 Unibus connector
M7258 Dataproducts interface printer controller (LP11)

I guess I've got a few questions about this machine. They go something
like this:

1. Does anyone have the pinouts for the serial line connector on the
DL11 board? I've
got the board, but the cable had been disconnected from it.

2. Does anyone know what that BM873-YJ board is? I'm just curious.

3. What would be the best way to get this old system running again? I've
got no
interface to that RX02 drive, and even if I did, I think half of it is
pretty well
broken - the plastic frame of the disk drive is cracked. I tried to glue
it, but
even if that worked, I imagine it must be terribly out of alignment now.
I thought
I remember someone asking about loading software over a serial line?

I've got my guesses as to what this system did in a past life. Perhaps
it ran as a
front-end for the IBM mainframe that the university ran, or perhaps it
served as a
router-type device on the MichNet network years back.. Maybe it didn't
do either of
these things. I'm not sure!

Thanks for any help!

--Sean Caron ( |
Received on Wed Jun 13 2001 - 09:25:27 BST

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