Jerome Fine wrote: . The PDT has no Qbus. I believe the eBay auction has a picture with the top cover off and the top board elevated - you can make out a ribbon cable coming off the bottom board, and the paper insulating sheet that sits between the bottom two boards when closed. The PDT-11/150 was reportedly available with one or two RX01 drives, and three serial ports with another three optional. I've only seen the one I own, which has both drives and six ports. There're no other expansion options that I can recall. In fact it's sitting in the dining room with a VT100 waiting to be powered up to check some 8" floppies I received a while back. I'm in the process of bringing up a VAX 4000/500 I recently received and it'd be a hoot to connect the PDT to it. Did RT-11 ever include DECnet support? Probably so, but as of what version? I don't recall seeing mention of it with whatever version came with the PDT, and I'd be amazed if the PDT could support it... --Steve. smj(at)spamfree.crash.com (lose spamfree to get through, m'kay?)