ASCII by Jason Scott

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A Very Successful DENCON —

As mentioned previously, the plan was set into motion many months ago to bring a little retrocomputing spirit to DEFCON.

That plan was successful.

Load-in was intense and a little late in the day on Thursday. I think my favorite moment of that was when we realized we needed a few more people to handle the moving of 300-600 pound machines on a very tiny liftgate, and I walked into the DEFCON contest area and asked ‘Who here wants to load a PDP-11 out of a truck?” One kind person stood up immediately and said “me”. And together, we made the load-in that much less painful. Here’s some quick candids of the truck and us working:

On the left in that last photo is Pavl Zachary, who is the owner of all this large-scale computing equipment. He and his crew loaded this stuff into a truck, drove 5 hours from California, and then worked for a good number of hours to bring all this various stuff out onto the floor we were assigned. By the time we had it all out, the place looked like a flea market from hell (or heaven, I suppose):

After hours beyond that of setting things up, we had ourselves a pretty damned impressive room, if I do say myself. I think the best part of being where we were in the layout was that throughout the weekend, people stumbled upon the setup, finding this incredible time capsule of computer technology active and functioning. ‘What do you mean, it works!?” was something I overheard a bunch of times. And really, one glance at this setup and you might be surprised it worked too:

Besides the incredibly functioning layout, we also had tables with tons of artifacts, and notes where possible to explain things. It was comprehensive enough that we were even able to convince Phreakmonkey to drop off his circa-1964 300bps modem for close inspection by the curious:

He gave an excellent presentation and demonstration of this modem, but he was up against a bunch of other talks – so the fact people could just check the thing out directly (look at that great woodwork!) made it that much cooler.

Pavl went above and beyond, loading up various operating systems over the weekend for people to try:

As for reactions that I witnessed, it was interesting.  Some people had never seen this equipment in person (in one hilarious moment, someone asked me where the PDP-11 was, while I was standing in front of the massive PDP-11) while others had worked at these machines for their jobs for years. One or two people claimed to have worked for Digital and played a part in the design of some of these things. And yet others were truly unaware of how truly massive and how underpowered by today’s standards these machines were.

By far, though, the most inspiring thing to me was the one attendee (I am not including pictures of them) who took to this opportunity at full bore. By the end of the event, they were actually keying in boot instructions into the keyswitches on the front of the PDP, utilizing the documentation and basically learning the absolutely core/base information an admin would need to get one of these monsters up and running, from bare metal. I’m talking hours of study to do this, to be able to work this panel properly:

To let someone have the opportunity to be able to literally reach back decades and learn a skill which is essentially being lost to the modern era – this is what drives me in being a part of computer history.  How could I not be delighted at everything that happened here?

The full set of photos is here.

Categorised as: computer history

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  1. Lorien says:

    That is SO COOL!! 🙂

  2. Ethan says:

    Stunning! I’m sorry I missed it (and I still _have_ a decent collection of DEC gear).

  3. jim s says:

    excellent collection, I am also sad to have missed this display. And thanks to those who had the equipment and took the time, expense and effort to show it at your show.

  4. Allison says:

    Being ExDEC millrat I’ve useed room of hardware just like that.. shiny!

    THat one is better looking than any of the engineering 11/70s!

  5. SigFLUP says:

    o my god, that’s the most wicked pdp setup I’ve every seen.

  6. Aaron Davies says:

    i was able to read pdp 8 machine code for about a month and a half in college (2001), as our computer hardware design project was to implement one in VHDL. our first exercise was to write a program to read a number from the keyboard, square it, and print it to the terminal. i think that took about a page of code, and we had to key the tape driver (twelve words, i think?) into the emulator we were using (since we hadn’t written the cpu yet) manually the first time around.

  7. 72 Degrees says:

    […] a bunch of times. And really, one glance at this setup and you might be surprised it worked too." An old-school, mainframe computer room assembled and operating at […]

  8. Jenny G says:

    That’s beautiful, man! This brings back memories – I programmed PDP-11 in school (mid-80s) and worked on a DEC VAX my first few years in the “real world.”

  9. fak3r says:

    Just wanted to thank you for doing this, it was one of the highlights of DEFCON last year for me, I’m still passing this link around to people 😉 I don’t want to know what a pain it was to get that there, setup….and working, so I just wanted to thank you and anyone else involved for the effort, it was epic.

    Are you guys planning on doing it again this year? (if so, beers will be on me)

  10. Manny says:

    Wow! Good to see all these images. It reminds me of the computer classes we learnt in our school where in we had this big equipment which were to be handled with utmost care. I have seen few images of Dencon on Flickr I suppose.

    I enjoyed reading through your posts and it is not surprising if someone asks you where the PDP 11 was.