[pups] Netcom HV-1148 QBus Backplane

azd30 azd30 at telus.net
Thu Oct 24 04:26:31 AEST 2013

Hi all,

I am hoping this list is still alive, since I'd like to find out a bit more info about this backplane.
It's part of an 11/23 system (based on CPU) that is made by Netcom. It had standard DEC 
cards in it DLV11, M8021 bootstrap board etc. Apparently the system ran a few years back
before it was put in storage. I aquired it, in the hopes of bringing it back to life and getting
it to successfully display a login: prompt.

I have read through the archives, esp. a post from Michael Sokolov back in 98, where he describes 
the different types of QBus'es. Q/Q, Q/CD etc.

It looks like the backplane that I have (according to some documents written at SLAC in late 70's) 
is a serpentine or sinusoidal.

A diagram on the cardcage describes as follows:


There is also a blurb about slot 2/CD being wired differently. Two slots on the diagram are pre-printed for RL controllers.

My CPU card is a later rev. D so it can do 22bit addressing. I'd like if possible to run 22bits, since this would allow
me at a later time to put in a 11/73 cpu that would run 2.11. 

How would I go about checking if the backplane is wired for 22bits or not. I seem to remeber the standard qbuses had the W1-W4 pins (?)
that you could wirewrap to change from 18to22, but this backplane has nothing like that.

Also, in the present configuration, with an 11/23 and 128Kw, could I run v6 or v7 (assuming I can get some form of supported disk storage)? At present
I only have a floppy controller and a bunch of 8" Shugart 801 drives..

thanks in advance for any replies.


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