This is an unusual one. The PDT-11/150 is one of a series of “smart terminals” based on the PDP-11/03’s LSI-11 chip set and so is basically a little PDP-11 atop a pair of massive 8″ disk drives.
It came to me from a friend who presides over a massive collection but is still, like the rest of us, unable to keep everything. His collection is mostly home machines and quite game focused and this business machine doesn’t fit and so I got a message.
This is just the kind of thing I love. The left-field, unloved and under appreciated machines like this are just the cut of my jib.
Details
Looking on the net there is not a lot of details on this one but according to the manual has 16 or 30 (sic) k-words of RAM, 2 8″ floppy drives and 6 serial ports. The processor is the LSI-11 in 3 chips.
From the front the machine is dominated by the floppy drives. The processor and all it’s additions are under the small “lid” and behind the smart label… 
The state of things.
It’s not working… I don’t think there is much wrong with it as when I apply power, the disks make moving noises, the LEDs on the front light and go out but I can’t get any life out of the serial port and onto my PC that’s running a serial terminal.
Things to do.
The run mode switch on the back had been bent and become a bit flaky. I’ve replaced it with a new one (RS part number 7109551) but it didn’t make it run properly. It did give me a feeling of satisfaction though 🙂
Raise pin 20 on the console serial port to tell the machine to run. A proper terminal connection should do this for you, but good to check.
Oh. DTR? Interesting.
Thanks for that. Next time I get it on the bench, I’ll give that a try.
Absolutely love seeing this restoration attempt. Very few people have ever heard of them let alone actually used one.
These are my holy grail machines since I used them in college in the early 1980s. I was a student lab tech for a computer lab that had two of these machines setup complete with VT100 terminals and DEC line printers. I used them to do homework and write term papers. I still have my 8 inch floppy disk media.
Hi Brian,
Thanks for the comment. They are interesting machines to be sure. It’s as it DEC weren’t sure how to respond to micros at the time.
This was my first computer circa ’84. Dad worked for DEC and they offered them to employees at a discount around the time the IBM PC came out. If my memory serves me, it actually had 60k of RAM. We got it with a full 24×80 VT52 terminal, and word processor, spreadsheet and database software. There were no graphics, but I still found quite a few games to play: Larn and Advent and even Space Invaders and Asteroids done with ASCII characters.