Date of production: 1981

CPU Type: KDF11-UA, 16bit, CISC

System bus: UNIBUS

Max. RAM without memory mapping module: 256 kB

Max. RAM with memory mapping module: 4096 kB

Serial number:




This nice PDP 11/24 system was kindly provided by a friend of mine around 2004 / 2005. There are inventory stickers on the housing, which indicate that this machine was in use at the DLR (Gesellschaft für Deutsche Luft- und Raumfahrt). This was my very first UNIBUS-based PDP-computer within my collection.

The system makes use of the extra-large cabinet, when being configured with two RL02 drives. This configuration was simply called: "RL02 system" by DEC. The left part of the cabinet serves to house all the cabling of the drives. Now if you carefully look at the picture, you can see that there's only one RL02 drive installed in the upper bay. The lower unit has been given away so tomebnody else before I was given the system. Below the PDP-computer is now a Fujitsu Super Eagle SMD-E drive, which can be connected to the PDP11 via an Emulex SMD-E controller.

Current setup and functionality:

The system box originally came with the CPU-module, the KT24 unibus mapping module, 1 Mbyte of memory (one board), and the RL02-controller.

I added three more 1MB memory boards to obtain the maximum amount of memory available. Addditionally, an EMULEX SC-41 SMD-E controller has been added.

The system worked fine until a try to install an EMULEX communications controller. Apparently, the board has a fault, which, in turn, damaged the CPU-board ! Thankfully, I have another spare CPU-board.

The Super-Eagle hard drive was given to me by the same person, who gave me the PDP 11/24. Unfortunately, the hard drive is not working, too. Its power supply has a fault. When the drive is turned on, one can hear the blowers for two seconds, before the power supply automatically shuts down again. Until now, I could find any documentation on Fujitsu's Super Eagle drives (model number: M2361A). There is only documentation for the former Eagle-drives available (M2351A), but their power supplies are different one than those in the Super-Eagles. If anybody has documentation for these drives, I'd be glad, if you could contact me, as I'd like to repair this unit.


More Pictures of the PDP 11/24: