DEC 11/73 systems

This page Last updated Jan 02 2010

To email me or to order, see see my ordering Web page for my email addresses.

To see other DEC systems and parts I have, visit my DEC reference page.

DEC 11/73 systems

In 2003 I acquired two Micro 11/73 systems, rack mount. Both come up and display at the console terminal. One has RSX-11 running some kind of "spectrometer" control/data acq. application; the other has a bad RD53A (Micropolis 1325D) MFM hard drive which shuts down. But the serial console is responsive andit runs through the start-up diagnostics. Both systems have TK50 tape drives, not tested. 1MB or 2MB memory apparently. Cabinet lable says "173QZ-D2" with Astec power supply AA12131, 345W on either. Cards below identified by model name on card tabs, descriptions are NOT GUARANTEED as every card not pulled and examined. Weight over 60 lbs.

The RSX11M booting 11/73 serial number ending in ...7064, has a TK50 tape drive and a RD53A hard drive, and the following cards:
M8190 KDJ11 CPU
M7551 MSV11 MOS RAM card
M7504 DEQNA with cable to DEQNA network connector
M7546 TQK-50 tape controller for TK50 & M7555 RQDX3 Winchester & floppy controller
--(RX50, RD50-54, RD31, RD32?) M9047 bus grant continuity
M9047 & M7513 RQDX expander, with cable to rear 50-pin connector
adac card 1953-0 or 1953BR, interface to some instrument..

When I powered up the system in 2003, the console said "RSX-11M V4.3 BLTO 1024K MAPPED"; some spectrometer setup messages; and "MAP 2048K 15.206MHz".

The nonbooting 11/73, serial number ending in ...6996, has a TK50 tape drive and a RD53A hard drive, and the following cards (check descriptions above):
M8190 KDJ11 CPU
M7551 MSV11 MOS RAM card
SKYMNK-02A-02 >> two quad width cards cabled together:
SKYMNK 02B-01 >> large chip Weitek 1516APC, PALs, etc.
---Sky Computer 1M flop 32-bit float co-processor for FFT calculations?
M7555 RQDX3 disk/floppy with internal cable & M7546 TQK-50 tape with internal cable
M7513 RQDX expander with cable to rear 50-pin connector & M7504 DEQNA network
adac card 1953-0 or 1953BR, interface to some instrument & CQD-200/M

CQD-200/M is by CMD Technology Inc,
--- w/50-pin flat cable connector
---and 10 pin connector. Has 8086 processor, NCR5386? chip, etc.
---SCSI disk controller with serial (RS232) interface.
Here's a hex dump of the two ROMs on board.

On this system, on startup I got messages like "0-07777776 2048Mb Qbus 17772100". The drive was noisy, spins up and down, then stops. Console 19.2Kbaud, testing numbers on rear display show 1...9.

DEC 11/73 systems in 2009

A DEC owner in Nov-Dec 2009 had a CQD200 card but no ROMS, and asked me for a copy of mine, which I provided. He tells me the CQD controller will actually work stand-alone through its serial port, to set up a SCSI drive and test it. He's done sysgens for various 11/73 DEC OS, and offered in exchange to set up a drive for me. In due course I'll take him up on it!

Other persons have expressed interest in helping me run these systems. As part of my "restoration and repair" activities, I dug these out of my storage, recovered the ROMS on that board, and made this Web page as I reviewed the hardware. I need to re-power these systems and see what they can still do.

11/73 w/float s/n...6996

Again, this system did not boot an OS. I photographed these cards, checking for condition and jumpers:

M8190 KDJ11 CPU quad width card
M7551 MSV11 MOS RAM quad width card
SKYMNK-02A-02 and SKYMNK 02B-01 quad width cards (see 2003 description)
M7555 RQDX3 disk/floppy card
M7546 TKQ50 tape controller with M7546 jumper area
M7513 RQDX expander drive extender card, to rear 50-pin
M7504 DEQNA network card
ADAC interface card not in use
CDQ200 SCSI controller card (not in use)

Copyright © 2009 Herb Johnson