My VAX 11/750

My 11/750 has 20 cards in it:

• L0002 11/750 CPU: Data path and micro sequencer
• L0003 11/750 CPU: Memory interface
• L0004 11/750 CPU: Unibus interface
• L0008 11/750 CPU: Patchable control store
• L0006 11/750 CPU: Diagnostic module
• L0016 11/750 CPU: 64K memory controller
• M8750 1MB ECC MOS memory, 64kbit chips
• M8750 1MB ECC MOS memory, 64kbit chips
• M8750 1MB ECC MOS memory, 64kbit chips
• M8750 1MB ECC MOS memory, 64kbit chips
• M8750 1MB ECC MOS memory, 64kbit chips
• M9202 Unibus connector
• M7454 TU80 tape drive controller
• M8396 DMF32 8 port async serial, 1 port sync serial, 1 parallel printer port
• M7819 DZ11 8 port serial async interface, full modem control
• M7819 DZ11 8 port serial async interface, full modem control
• M7819 DZ11 8 port serial async interface, full modem control
• M7486 UDA 50 SDI disc drive controller board 2
• M7485 UDA 50 SDI disc drive controller board 1
• M9313 Unibus exercisor and terminator

If you are looking for technical details about these cards I recommend The VAX 11/750 FAQ, a great and detailed source of technical information about the 11/750.

You will note my 11/750 has no Ethernet card installed. However, I recently was able to trade one for a graphics card, so a DELUA will be in there shortly! My only remaining wish now is a SMD disc controller card. Read on...

History

This 11/750 was used at the Hogere Agrarische School in Den Bosch to teach the students how to use agricultural software. When its day in the sun had passed the management wanted to scrap it and replace it with a Novell network. Fortunately, a HAM radio amateur at the school heard of this and told everyone who wanted to hear it that this beautiful computer would soon cease to be. The message reached me and the rest is history. The VAX came with 24 terminals, 8 printers, 3 crates of tapes and miles and miles of manuals. I had to borrow a truck with a special suspension system to transport the VAX without damaging the drive and 6 friends helped me load and unload all the stuff.

The VAX used to run NetBSD 1.1. It took some doing to get the OS on the RA81, because there was no boot medium with NetBSD on it to be had. I hooked the RA81 up to a MicroVAX II which had a TK50 tape drive and a SDI disc controller, installed NetBSD and hooked the drive back to the 11/750.

I don't use the VAX at the moment, because the RA81 has crashed. It had a real actual unrepairable screaming head crash. That happens to all RA81s sooner or later. The disc pack is driven with a belt that has a very high tension. The bearings of the pack are not sturdy enough, so at some moment in time the disc pack starts tilting over ever so slightly, and *BANG*... head crash.

Fortunately I am not lost to the VAX community, because I now also have a number of MicroVAX II and VS3100 machines. I am looking for a SMD disc controller card, because I have enough very sturdy SMD drives around here, which would be very suitable for the 11/750. However, I have hopes of getting the 11/750 to work again, because I recently got a VS3500 with a RA70 in it. I plan to install NetBSD on the RA70 and hook it up to the 11/750. Let's hope it will work...

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