Module Comparisons Third-Party Products Functional Information

PDP-11 Q-bus Information Page


I first created this area in September of 2014 to provide information for DEC Q-bus system builders, like myself, who want a single site that provides module comparisons and information on best practices.

I had wanted own a PDP-11 for some years, and like many, my intent was to eventually get Unix running on it. I was somewhat familiar with UNIBUS systems, but consider these machines impractical to own, due to their size, complexity, and power and cooling requirements. The ongoing maintenance would also likely consume more of my time than I would want. Also, because all of the early Unix development was done on UNIBUS systems, I never really paid much attention to the Q-bus products.

One evening, while surfing the web for something completely unrelated, I stumbled across Diane Neisius' PDP-11 Page. After seeing her LSI-11/2-based system and the tinkering she has done, I became fascinated with Q-bus systems. In researching these systems, I had difficulty in finding good comparisons between components, and the information that was available was fragmented.

To aid in my research, I created this area to navigate through all of the components and to help those, who want to build their own PDP-11 system, determine which components they would need. Fortunately, original DEC documentation is easy to come by and provided most of the information found here. One site that was a huge help was VaxHaven which has done a great job of obtaining and organizing most of the available DEC documentation. Of course, the greatness of Al Kossow's Bitsavers was a huge help, as well.

My point-of-view is that of a hobbiest, rather than a historical preservationist. Therefore, in my summaries of the items in these pages, I tend to value components according to their usefulness, which may run counter to the view of others.

The links on the left contain my comparisons of various component groups and their different capabilities. In addition, other articles will be provided to help clarify murky topics.

This site is still very much a work in progress and I plan to add to it regularly. My goal was to build a PDP-11 of my own. When researching and shopping for components I refer to these pages quite regularly. Hopefully, the information provided here is accurate, and will be equally as helpful to others.


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